JP2007290111A - Polishing method and polishing apparatus - Google Patents

Abstract

Even if a polishing object has a large diameter, the yield of the polishing object is reduced by suppressing the occurrence of scratches on the polished surface of the polishing object due to foreign matter adhering to the surface of the polishing member. To be able to suppress this.
A polishing method for polishing a polishing object by moving the polishing member and the polishing object relative to each other while applying pressure between the polishing member and the polishing object. The foreign matter adhesion position or foreign matter adhesion range is specified, and the foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member is intensively cleaned.
[Selection] Figure 4

Description

  The present invention relates to a polishing method and polishing apparatus for polishing optical parts, mechanical parts, ceramics, metals, and the like, a program for realizing the polishing method, and a storage medium storing the program, and more particularly, a polishing target of a semiconductor wafer or the like The present invention relates to a polishing method and a polishing apparatus suitable for polishing a surface of an object flat and mirror-like, a program for realizing the polishing method, and a storage medium storing the program.

  In recent years, with the progress of high integration of semiconductor devices, circuit wiring has been miniaturized, and the dimensions of the integrated devices are being further miniaturized. Therefore, a process for removing the film formed on the surface of the semiconductor wafer by polishing and flattening the surface is required. As one of the planarization methods, there is polishing by a chemical mechanical polishing (CMP) apparatus. The chemical mechanical polishing apparatus includes a polishing member (polishing cloth, polishing pad, etc.) and a holding unit (top ring, polishing head, chuck, etc.) that holds an object to be polished such as a semiconductor wafer. Then, the surface of the object to be polished (surface to be polished) is pressed against the surface of the polishing member, and a polishing aid (abrasive solution, chemical solution, slurry, pure water, etc.) is supplied between them, and both are moved relative to each other. Thus, the surface of the object to be polished is polished flat and mirror-like. It is known that in the polishing by the chemical mechanical polishing apparatus, good polishing is performed by the chemical polishing action and the mechanical polishing action.

  As a material (raw material) of a polishing member used in such a chemical mechanical polishing apparatus, a foamed resin or a nonwoven fabric is generally used. Fine irregularities are formed on the surface of the polishing member, and the minute irregularities act as chip pockets effective for preventing clogging and reducing polishing resistance. However, if polishing of the object to be polished is continued with the polishing member, fine irregularities on the surface of the polishing member are crushed, causing a reduction in the polishing rate. For this reason, it is necessary to perform dressing (sharpening) on the surface of the polishing member with a diamond dresser or the like in which a large number of diamond particles are electrodeposited to re-form fine irregularities on the surface of the polishing member.

  During the dressing, diamond particles may fall off the dresser or dressing waste may be generated. Diamond particles and dressing debris that have fallen from the dresser are discharged from the surface of the polishing member together with a cleaning liquid that is normally supplied during dressing. However, if it remains on the surface of the polishing member without being discharged, it becomes a foreign substance and causes scratches on the polished surface (polishing surface) of the object to be polished.

  In addition to diamond particles and dressing debris generated during dressing, film debris generated during polishing of films such as oxide films and metal films, scraps of polishing members, and abrasive grains contained in polishing aids are aggregates It adheres to the surface of the polishing member and becomes a foreign matter that causes scratches on the polished surface (polished surface) of the object to be polished. If the object to be polished is a semiconductor wafer, such a scratch is likely to be a fatal defect, which is a serious problem. In addition, if the polishing is continued with foreign matter attached to the surface of the polishing member, scratching continues on the surface of the object to be polished until the foreign object is removed from the surface of the polishing member. For this reason, not only one object to be polished, A defect occurs in a plurality of objects to be polished, which causes a decrease in yield.

  As described above, scratches generated on the surface of the object to be polished are highly likely to be fatal defects, and various methods and apparatuses for removing foreign substances adhering to the surface of the polishing member have been proposed to prevent such scratches. . For example, a method of washing a foreign material on a polishing member by spraying a cleaning liquid such as pure water or a chemical solution on the polishing member, and a polishing apparatus equipped with the device have been proposed (see Patent Document 1 and Patent Documents 3 to 10). In addition, a method for removing foreign substances from the surface of the polishing member by spraying a cleaning liquid on the polishing member and rubbing the surface of the polishing member with a brush, a grindstone, a PVA sponge scrub, or the like, and a polishing apparatus equipped with the device have been proposed ( (See Patent Documents 3 and 4 and Patent Documents 6 to 8). In addition, there has been proposed a polishing apparatus that is provided with a device for sucking slurry and sucks the slurry that contributes to the foreign matter and removes it from the surface of the polishing member (see Patent Document 1). Further, a polishing apparatus provided with a fluid bath for cleaning the polishing member during polishing has been proposed (see Patent Document 4). Furthermore, a method of dissolving foreign matter with a solution such as peroxosulfuric acid or hydrofluoric acid, and a polishing apparatus equipped with such a device have been proposed (see Patent Documents 2 and 8).

  In addition, in order to improve the conditions of the polishing process in which scratches occur and the polishing apparatus itself, the scratch generated on the polished surface (polishing surface) of the object to be polished is analyzed, and the polishing apparatus and its conditions involved in scratch formation, There has been proposed a scratch analysis method and a scratch analysis apparatus that specify the position of a foreign substance adhering to a polishing member (see Patent Document 11).

JP-A-10-94964 JP-A-10-217104 JP-A-10-244458 JP-A-10-296625 Japanese Patent Laid-Open No. 11-243072 JP-A-11-333695 JP 2000-218517 A JP 2000-280163 A JP 2000-340531 A JP 2001-1444055 A JP 2004-259871 A

  However, it is difficult to completely prevent the occurrence of scratches on the polished surface (polished surface) of the object to be polished by removing the foreign matter adhering to the polishing member. As a cause of this, as the diameter of the polishing object is increased, the area of the polishing member that comes into contact with the surface of the polishing object (surface to be polished) increases, resulting in unevenness in spraying the cleaning liquid or rubbing the brush. It is mentioned that the foreign matter adhering to the surface cannot be effectively removed. On the other hand, it may be caused by the fact that the surface of the polishing member is not uniformly removed due to excessive cleaning of the surface of the polishing member, and the foreign material on the surface of the polishing member cannot be removed.

  Note that the scratch analysis method and the scratch analysis apparatus disclosed in Patent Document 11 are not linked to a polishing apparatus, and therefore, scratches are generated on the surface of an object to be polished by a polishing apparatus operating in a mass production line. It is thought that it is impossible to respond immediately when it occurs, and it is impossible to suppress a decrease in yield.

  The present invention has been made in view of the above circumstances, and even if the polishing object has a large diameter, scratches occur on the surface after polishing of the polishing object due to foreign matter adhering to the surface of the polishing member, Polishing method and polishing apparatus capable of suppressing reduction in yield, and adhesion region specifying method and adhesion region specifying device for specifying foreign material adhesion region, polishing method and adhesion region specifying method An object is to provide a program and a storage medium storing the program.

  The invention according to claim 1 is a polishing method for polishing the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object. A polishing method characterized in that a foreign matter adhesion position or a foreign matter adhesion range on the polishing member surface is specified, and the foreign matter adhesion position or foreign matter adhesion range on the polishing member surface is intensively washed.

  Accordingly, for example, after the polishing is stopped, the foreign matter adhesion position or the foreign matter adhesion range on the surface of the polishing member is intensively washed, so that the removal operation of the foreign matter from the surface of the polishing member can be effectively performed.

  The invention according to claim 2 is a polishing method for polishing the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object. The polishing method is characterized in that information on the important cleaning position or the important cleaning range on the surface of the polishing member is read from a storage medium into a computer, and the important cleaning position or the important cleaning range on the surface of the polishing member is intensively cleaned.

  As a result, the position or range where the foreign matter is frequently attached or the position or range particularly important for the polishing yield is stored in the storage medium as the important cleaning position or the important cleaning range on the surface of the polishing member. Adhering foreign substances on the surface of the polishing member can be prevented.

  The invention according to claim 3 is a polishing method for polishing the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object. , Reading information on the important cleaning position or important cleaning range of the polishing member surface from a storage medium to a computer, specifying the foreign matter adhesion position or foreign matter adhesion range on the polishing member surface, and the important cleaning position or important cleaning range of the polishing member surface, And at least one of a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member.

  As a result, for example, when no foreign matter is detected on the surface of the polishing member during polishing, and the foreign matter attachment position or foreign matter attachment range on the polishing member surface is not specified, the focus cleaning position or the critical cleaning range on the polishing member surface is preferentially cleaned. If foreign matter is detected on the surface of the polishing member, the position or range of attachment of the polishing member is carefully washed to effectively prevent foreign matter from adhering to the surface of the polishing member and to remove foreign matter after the foreign matter has been attached. It can be carried out. In addition, you may wash | clean intensively including the adhesion position or adhesion range of the said foreign material, and a range wider than it.

  The invention according to claim 4 is a polishing method for polishing the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object. The foreign matter adhesion position or foreign matter adhesion range on the polishing member surface is specified, the foreign matter adhesion position or foreign matter adhesion range on the polishing member surface is stored and accumulated, and the accumulated foreign matter adhesion position or foreign matter adhesion range on the abrasive member surface is stored. From this, the important cleaning position or the important cleaning range is calculated, and at least one of the calculated important cleaning position or the important cleaning range on the surface of the polishing member and the foreign matter adhesion position or the foreign matter adhesion range on the specified polishing member surface is emphasized. This is a polishing method characterized by cleaning.

  As a result, the position or range of the polishing member surface with a high frequency of foreign matter adhesion is calculated from the accumulated foreign matter adhesion position or foreign matter adhesion range on the polishing member surface, and is stored in the storage medium as the critical cleaning position or the critical cleaning range. Can do. Further, as the polishing time is longer, the amount of accumulated information on the foreign matter adhesion position or foreign matter adhesion range on the polishing member surface increases, so the accuracy of the important cleaning position or important cleaning range on the polishing member surface increases. Therefore, it is possible to effectively remove the adhered foreign matter, and more efficiently perform cleaning for preventing the foreign matter from adhering to the surface of the polishing member.

  The invention according to claim 5 is characterized in that a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member is specified by detecting that a foreign matter has adhered to the surface of the polishing member by a detection unit. , 3 or 4.

  Thus, by detecting the adhesion of the foreign matter to the surface of the polishing member by the detection unit, the polishing can be stopped immediately upon detection of the foreign matter. In addition, after polishing is stopped, the surface of the polishing member is cleaned to remove foreign matter, or the polishing member is replaced to prevent scratches on the polished surface (polishing surface) of the object to be polished. can do. In particular, by detecting foreign matter on the surface of the polishing member by the contact method, foreign matter on the surface of the polishing member can be detected with high accuracy even if there is a liquid film on the surface of the polishing member.

The invention according to claim 6 is the polishing method according to claim 5, wherein the surface of the polishing member is image-analyzed to detect that a foreign matter has adhered to the surface.
Thereby, contamination of the polishing member or the like by the detection unit can be prevented.

The invention according to claim 7 is characterized by diagnosing the polished surface of the polishing object after polishing, and specifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member. The polishing method described.
There is a correlation between a scratch generated on the polished surface (polishing surface) of the object to be polished and a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member. For this reason, it is possible to determine the foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member from the scratch generation position by diagnosing the polished surface of the object to be polished and detecting scratches generated on the surface. it can. Therefore, the foreign matter adhesion position or the foreign matter adhesion range on the surface of the polishing member can be intensively cleaned, and foreign matters can be effectively removed.

The invention according to claim 8 is the polishing method according to claim 7, wherein the polished surface is diagnosed by image analysis of the polished surface of the polishing object after polishing.
Thereby, for example, whether or not the scratch due to the foreign matter generated on the polished surface of the polishing object (polishing surface) is a fatal defect, only the scratch that became a fatal defect is extracted, From this extracted scratch, it is possible to specify the foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member that generates a fatal scratch. Therefore, when the scratch due to the foreign matter is fatal, the polishing can be stopped immediately, and the reduction in the yield can be suppressed by intensively cleaning the foreign matter attachment position or the foreign matter attachment range on the surface of the polishing member.

  According to the ninth aspect of the invention, the surface of the polishing member is diagnosed, and the foreign material adhesion position or the foreign material adhesion range on the surface of the polishing member is specified as the position or range to be cleaned intensively. A method for identifying a cleaning region on a surface of an abrasive member, wherein the position or range to be cleaned is stored and stored.

  The invention according to claim 10 polishes the polishing object by moving the polishing member and the polishing object relative to each other while applying pressure between the polishing member and the polishing object, and polishing the polishing object. In this method, the polishing surface of the polishing member is specified by diagnosing the polishing surface of the polishing member and specifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member to be intensively cleaned.

  The invention according to claim 11 stores and accumulates information specified as a foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member, and stores the accumulated information on the surface of the polishing member according to claim 10. It is.

The invention according to claim 12 is the method for specifying the cleaning region of the surface of the polishing member according to claim 10, wherein the polishing surface is diagnosed by performing image analysis on the polishing surface of the object to be polished.
Thus, by storing and storing the specified information, the stored information can be used for calculation of the important cleaning position or the important cleaning range.

A thirteenth aspect of the present invention is an attachment region specifying method characterized in that an image obtained by photographing a polished surface of an object to be polished is subjected to image analysis to specify a foreign matter attachment position or a foreign matter attachment range on the surface of the polishing member.
Thereby, for example, when a scratch occurs on the polishing surface of the object to be polished, by analyzing the image of the polishing surface, it is possible to specify the foreign matter attachment position or the foreign matter attachment range on the surface of the polishing member. It is possible to efficiently remove foreign substances from the surface of the polishing member.

The invention described in claim 14 is a polishing apparatus that polishes the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object. , An adhesion region specifying part for specifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member, and a cleaning unit for mainly cleaning the foreign matter adhesion position or the foreign matter adhesion range on the surface of the polishing member specified by the adhesion region specification unit A polishing apparatus characterized by comprising:
Accordingly, for example, after the polishing is stopped, the foreign matter removal position or the foreign matter attachment range on the surface of the polishing member is intensively washed, so that an effective foreign matter removal operation can be performed.

The invention according to claim 15 is a polishing apparatus for polishing the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object. Read the information from the cleaning unit for cleaning the polishing member surface and the storage medium storing the information on the important cleaning position or important cleaning range of the polishing member surface, and focus on the important cleaning position or important cleaning range of the polishing member surface. A polishing apparatus comprising a control unit that controls the cleaning unit to perform cleaning.
As a result, it is possible to prevent adhesion of foreign substances that cause scratches to the surface of the polishing member.

  The invention according to claim 16 is a polishing apparatus that polishes the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object. A cleaning unit that cleans the surface of the polishing member, an attachment region specifying unit that specifies a foreign matter adhesion position or a foreign matter adhesion range on the polishing member surface, and a storage medium that stores information on the important cleaning position or important cleaning range of the polishing member surface Read the information and focus on at least one of the important cleaning position or important cleaning range of the read polishing member surface and the foreign matter adhesion position or foreign matter adhesion range of the polishing member surface specified by the adhesion region specifying unit. A polishing apparatus comprising a control unit that controls the cleaning unit to perform cleaning.

  As a result, for example, when no foreign matter is detected on the surface of the polishing member during polishing, and the foreign matter attachment position or foreign matter attachment range on the polishing member surface is not specified, the focus cleaning position or the critical cleaning range on the polishing member surface is preferentially cleaned. If foreign matter is detected on the surface of the polishing member, it is possible to prevent the foreign matter from adhering to the surface of the polishing member and to remove the foreign matter after the foreign matter has been attached by focusing on the position or range of attachment. Can be implemented.

  The invention described in claim 17 is a polishing apparatus that polishes the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object. A cleaning unit that cleans the surface of the polishing member, an adhesion region specifying unit that specifies a foreign material adhesion position or a foreign material adhesion range on the polishing member surface, and a foreign material adhesion position or foreign material on the surface of the polishing member specified by the adhesion region specifying unit The adhesion range is stored and accumulated, the important cleaning position or the important cleaning range is calculated from the accumulated foreign matter adhesion position or foreign matter adhesion range on the accumulated polishing member surface, and the calculated important cleaning position or emphasis on the polishing member surface is calculated. The cleaning so that at least one of the cleaning range and the foreign matter adhesion position or the foreign matter adhesion range on the surface of the polishing member specified by the adhesion region specifying unit is mainly cleaned. A polishing apparatus characterized by comprising a control unit for controlling.

  As a result, the position or range of the polishing member surface where the frequency of adhesion of foreign matter is high is calculated from the accumulated position or range of foreign matter adhesion to the surface of the polishing member, and stored as the important cleaning position or important cleaning range of the polishing member surface. It can be stored on a medium. In addition, the longer the polishing time, the greater the amount of accumulated foreign matter adhesion position or adhesion range information on the polishing member surface, so that the precision of the important cleaning position or important cleaning range on the polishing member surface increases. Accordingly, it is possible to effectively remove the adhered foreign matter and to perform cleaning for more effectively preventing the foreign matter from adhering. Further, the data regarding the adhesion position or adhesion range of the foreign matter on the surface of the polishing member accumulated by the present polishing apparatus, or the important cleaning position or the important cleaning range of the polishing member surface calculated from these can be used in other polishing apparatuses. For example, when adding a new polishing device in addition to the existing polishing device, the data accumulated in the existing polishing device can be used by the new polishing device. Adhesion can be prevented.

The invention according to claim 18 is characterized in that the adhesion region specifying part has a detection part for detecting a foreign matter attached to the surface of the polishing member, and specifies a foreign matter attachment position or a foreign matter attachment range on the surface of the polishing member. The polishing apparatus according to claim 14, 16 or 17.
As a result, during the polishing, it is possible to take measures such as stopping the polishing by detecting that the foreign matter has adhered to the surface of the polishing member by the detection unit. In particular, by providing the detection unit in the polishing unit, foreign matter adhering to the surface of the polishing member can be detected immediately. Further, by detecting the foreign matter on the surface of the polishing member by the contact method, the foreign matter on the surface of the polishing member can be accurately detected even if there is a liquid film or the like on the surface of the polishing member.

The invention according to claim 19 is characterized in that the adhesion region specifying part has an image analysis device for detecting foreign matter adhering to the surface by image analysis of the surface of the polishing member. Device.
Thereby, it can prevent that a polishing member etc. are contaminated by the detection part.

The invention according to claim 20 is characterized in that the adhesion region specifying unit has a diagnostic device for diagnosing a polished surface after polishing of an object to be polished and specifying a foreign substance adhesion position or a foreign substance adhesion range on the surface of the polishing member. The polishing apparatus according to claim 14, 16 or 17.
There is a correlation between a scratch generated on the polished surface (polishing surface) of the object to be polished and a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member. For this reason, it is possible to determine the foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member from the scratch generation position by diagnosing the polished surface of the object to be polished and detecting scratches generated on the surface. it can. Therefore, the foreign matter adhesion position or the foreign matter adhesion range on the surface of the polishing member can be intensively cleaned, and foreign matters can be effectively removed.

The invention according to claim 21 is the polishing according to claim 20, wherein the diagnostic device is an image analysis device for diagnosing the polished surface by image analysis of the polished surface of the polishing object after polishing. Device.
Thereby, for example, whether or not the scratch due to the foreign matter generated on the polished surface of the polishing object (polishing surface) is a fatal defect, only the scratch that became a fatal defect is extracted, From this extracted scratch, it is possible to specify the foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member that generates a fatal scratch. Therefore, when the scratch due to the foreign matter is fatal, the polishing can be stopped immediately, and the reduction in the yield can be suppressed by intensively cleaning the foreign matter attachment position or the foreign matter attachment range on the surface of the polishing member.

According to a twenty-second aspect of the present invention, the control unit stores and accumulates information specified by the attachment region specifying unit as a foreign matter attachment position or a foreign matter attachment range on the surface of the polishing member. The polishing apparatus described in 1.
Thereby, the accumulated information can be used for calculation of the important cleaning position or the important cleaning range on the surface of the polishing member.

  The invention according to claim 23 is an apparatus for identifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of a polishing member, and a reading device for reading a standard pattern from a storage medium, and an image obtained by photographing a polished surface of an object to be polished. A reading device for reading a foreign matter, an arithmetic device for identifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member by performing image analysis using the read standard pattern and image, and a foreign matter adhesion position specified by the computing device Or it is an adhesion area specific | specification apparatus characterized by having an output device which outputs a foreign material adhesion range.

  Thus, for example, when a scratch occurs on the polishing surface of the object to be polished, polishing is performed by image analysis using a standard pattern prepared in advance and an image obtained by photographing the polishing surface of the object to be polished. It is possible to specify the foreign matter adhesion position or the foreign matter adhesion range on the member surface. Accordingly, it is possible to effectively remove foreign substances from the surface of the polishing member. Needless to say, the reading device for reading the standard pattern and the reading device for reading the photographed image may be devices having both functions.

  The invention according to claim 24 is an apparatus for specifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member, the reading device for reading the geometric parameters of the polishing device and the polishing conditions of the object to be polished, A standard pattern creation device that creates a standard pattern using the read geometric parameters and polishing conditions, a read device that reads an image of a polished surface of an object to be polished, the created standard pattern, and the read An arithmetic unit that identifies a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member by performing image analysis using the image, and an output device that outputs the foreign matter adhesion position or the foreign matter adhesion range identified by the arithmetic device This is an adhesion area specifying device.

  As a result, a standard pattern can be created using the geometric parameters of the polishing apparatus read above and the polishing conditions of the object to be polished, so there is no need to prepare and prepare a standard pattern in advance. Further, for example, when a scratch occurs on the polishing surface of the object to be polished, an image obtained by photographing the polishing surface of the polishing object read from the standard pattern created as described above and the reading device that reads the image is used. Using the image analysis with the above arithmetic unit, it is possible to identify the foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member. Accordingly, it is possible to effectively remove foreign substances from the surface of the polishing member. Further, the reading device that reads the geometric parameters of the polishing device and the polishing conditions of the object to be polished, and the reading device that reads an image obtained by photographing the polishing surface of the object to be polished have both functions. It goes without saying that it is also good.

In the invention according to claim 25, in order to remove foreign matter adhering to the surface of the polishing member by cleaning, an attachment region specifying procedure for specifying the foreign matter attachment position or foreign matter attachment range on the polishing member surface is emphasized in the computer. Read priority cleaning condition reading procedure from the storage medium, and a focused cleaning procedure for cleaning the foreign substance adhesion position or foreign substance adhesion range on the surface of the specified polishing member under the read critical cleaning condition , Is a program for executing.
Thereby, it is possible to cause the computer to execute an adhesion region specifying procedure, an important cleaning condition reading procedure, and an important cleaning procedure for cleaning foreign matter adhering to the surface of the polishing member.

In the invention described in claim 26, in order to prevent the adhesion of foreign matters to the surface of the polishing member, the computer reads the information on the important cleaning position or the important cleaning range of the polishing member surface from the storage medium, The important cleaning condition reading procedure for reading the cleaning conditions when the abrasive member surface is mainly cleaned from the storage medium, and the important cleaning position or the important cleaning range of the read abrasive member surface with the read important cleaning conditions This is a program for executing an intensive cleaning procedure for cleaning.
Thereby, in order to prevent adhesion of foreign matter to the surface of the polishing member, it is possible to cause the computer to execute an important cleaning region reading procedure, an important cleaning condition reading procedure, and an important cleaning procedure.

  According to a twenty-seventh aspect of the present invention, in order to prevent foreign matter from adhering to the surface of the polishing member or to remove foreign matter adhering to the surface of the polishing member by washing, the computer is provided with a focus cleaning position or a focus cleaning on the surface of the polishing member. The priority cleaning region reading procedure for reading information on the range from the storage medium, the adhesion region specifying procedure for specifying the foreign material adhesion position or the foreign material adhesion range on the surface of the polishing member, and the cleaning conditions for intensive cleaning of the polishing member surface Read the important cleaning condition reading procedure, and the read important cleaning position or important cleaning range of the surface of the polishing member, and at least one of the specified foreign material adhesion position or foreign material adhesion range of the polishing member surface This is a program for executing a priority cleaning procedure for cleaning under priority cleaning conditions.

  This prevents the adhesion of foreign matter to the surface of the polishing member, or removes the foreign matter attached to the surface of the polishing member by washing, so that the focused cleaning region reading procedure for cleaning the foreign matter attached to the surface of the polishing member is attached. It is possible to cause the computer to execute the region specifying procedure, the important cleaning condition reading procedure, and the important cleaning procedure.

  According to the twenty-eighth aspect of the present invention, in order to prevent foreign matter from adhering to the surface of the polishing member or to remove foreign matter adhering to the surface of the polishing member by cleaning, the foreign matter attachment position or foreign matter adhesion on the surface of the polishing member is removed. Adhesion area specifying procedure for specifying the range, adhesion area storing procedure for storing and accumulating the foreign substance adhesion position or foreign substance adhesion range on the surface of the polishing member, focused cleaning from the accumulated foreign substance adhesion position or foreign substance adhesion range on the polishing member surface Priority cleaning region calculation procedure for calculating position or intensive cleaning range, intensive cleaning condition reading procedure for reading cleaning conditions when intensively cleaning the polishing member surface from the storage medium, and intensive cleaning of the calculated polishing member surface At least one of the position or the critical cleaning range and the foreign matter adhesion position or foreign matter adhesion range on the surface of the specified polishing member is read. An intensive cleaning procedure of washing with the wash conditions is a program for execution.

  This prevents adhesion of foreign matter to the surface of the polishing member, or removes foreign matter attached to the surface of the polishing member by cleaning. It is possible to cause the computer to execute a storing procedure, a priority cleaning region calculation procedure, a priority cleaning condition reading procedure, and a priority cleaning procedure.

According to a twenty-ninth aspect of the present invention, the adhesion region specifying procedure detects that a foreign substance has adhered to the surface of the polishing member by a detection unit, and specifies an adhesion position or a foreign substance adhesion range on the surface of the polishing member. 29. The program according to claim 25, 27 or 28, which is an area specifying procedure.
Thereby, it is possible to cause the computer to execute an attachment region specifying procedure in which the detection unit detects that a foreign substance has adhered to the surface of the polishing member.

30. The program according to claim 29, wherein the adhesion region specifying procedure includes a procedure of performing image analysis on the surface of the polishing member and detecting that a foreign matter has adhered to the surface. It is.
Thereby, it is possible to cause the computer to execute an attachment region specifying procedure including a procedure for analyzing the image of the surface of the polishing member and detecting that a foreign matter has adhered to the surface.

The invention according to claim 31 is an adhesion region specifying procedure in which the adhesion region specifying procedure diagnoses a polished surface of the polishing object after polishing and specifies a foreign material adhesion position or a foreign material adhesion range on the surface of the polishing member. 29. The program according to claim 25, 27, or 28.
Thereby, the grinding | polishing surface after grinding | polishing of a grinding | polishing target object can be diagnosed, and the computer can perform the adhesion area | region identification procedure which specifies the foreign material adhesion position or foreign material adhesion range on the said polishing member surface.

The invention according to claim 32 is characterized in that the attached region specifying procedure includes a procedure of diagnosing the polished surface by image analysis of the polished surface after polishing of the polishing object. It is.
Thereby, it is possible to cause the computer to execute an adhesion region specifying procedure including a procedure of performing image analysis on the polished surface after polishing of the polishing object and diagnosing the polished surface.

According to a thirty-third aspect of the present invention, in order to store and accumulate the foreign matter attachment position or foreign matter attachment range, the computer diagnoses the surface of the polishing member and focuses the foreign matter attachment position or foreign matter attachment range on the polishing member surface. And a procedure for storing and storing the specified position or range to be cleaned intensively.
Thereby, it is possible to cause the computer to execute a procedure for storing and accumulating the foreign substance adhesion position or the foreign substance adhesion range.

The invention according to claim 34 is characterized in that the polishing member and the object to be polished are applied to the computer while pressure is applied between the polishing member and the object to be polished in order to specify the position or range of the foreign object attached to the surface of the polishing member. A procedure for polishing the object to be polished by moving the object relative to the object, and diagnosing a polishing surface of the object to be polished, and specifying a foreign substance adhesion position or a foreign substance adhesion range on the surface of the polishing member to be intensively cleaned This is a program for executing an adhesion area specifying procedure.
Thereby, it is possible to cause the computer to execute a procedure for specifying the foreign matter adhesion position or the foreign matter adhesion range on the surface of the polishing member.

According to a thirty-fifth aspect of the present invention, in order to store and accumulate the specified foreign matter attachment position or foreign matter attachment range, information specified as the foreign matter attachment position or foreign matter attachment range on the surface of the polishing member is stored in a computer. 35. The program according to claim 34, further executing a storing procedure.
Accordingly, it is possible to cause the computer to execute a procedure for storing and accumulating the specified foreign substance adhesion position or foreign substance adhesion range.

The invention according to claim 36 is the program according to claim 34, wherein the adhesion region specifying procedure includes a procedure of diagnosing the polished surface by image analysis of the polished surface of the object to be polished. .
Thereby, it is possible to cause the computer to execute an adhesion region specifying procedure including a procedure for analyzing the image of the polished surface of the object to be polished and diagnosing the polished surface.

According to a thirty-seventh aspect of the present invention, in order to identify the foreign matter adhesion position or the foreign matter adhesion range on the surface of the polishing member, the computer analyzes the image obtained by photographing the polishing surface of the object to be polished, thereby attaching the foreign matter to the surface of the polishing member This is a program for executing an attachment region specifying procedure for specifying a position or a foreign matter attachment range.
Thereby, it is possible to cause the computer to execute an adhesion region specifying procedure for specifying the foreign material adhesion position or the foreign material adhesion range on the surface of the polishing member.

A thirty-eighth aspect of the invention is a computer-readable storage medium in which the program according to any one of the twenty-fifth to thirty-sixth aspects is recorded.
The invention according to claim 39 is a polishing apparatus that polishes the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object. A polishing apparatus comprising a computer capable of reading a program from the storage medium according to claim 38 and executing the program.
As described above, by recording a program on a computer-readable storage medium, and reading and executing the program from the storage medium, it is possible to provide a polishing apparatus that suppresses a decrease in yield due to generation of scratches.

The invention described in claim 40 is a computer-readable storage medium in which the program described in claim 37 is recorded.
The invention according to claim 41 is an apparatus for specifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member, and can read the program from the storage medium according to claim 40 and execute the program It is an attachment area | region identification apparatus characterized by having.
In this way, by recording a program on a computer-readable storage medium, and reading and executing the program from the storage medium, the position or area of foreign matter adhesion on the surface of the polishing member that causes scratching is specified. An adhesion area specifying device can be provided.

  According to the present invention, even if the object to be polished has a large diameter, it is possible to suppress a decrease in yield due to scratches caused by foreign matters attached to the polishing member. That is, when the foreign matter adhering to the surface of the polishing member is detected, the polishing is stopped, the surface of the polishing member is washed, or the polishing member is replaced, so that a decrease in yield due to scratches can be suppressed. In addition, it is effective to specify the foreign matter adhesion position or foreign matter adhesion range on the polishing member surface, and to wash the foreign matter adhesion position or foreign matter adhesion range on this polishing member surface intensively after stopping polishing or during polishing. It is possible to suppress a decrease in yield due to scratching by performing a foreign object removal operation. Furthermore, it is possible to efficiently prevent foreign matters from adhering to the surface of the polishing member, and to suppress a decrease in yield due to scratches.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
First, the “foreign matter adhesion position and foreign matter adhesion range” when foreign matter adheres to the surface of a polishing member such as a polishing pad will be described with reference to FIG. In general, a polishing member such as a polishing pad during polishing is not stationary, and as shown in FIG. 1A, in the case of a rotary polishing member 200, the rotational movement is as shown in FIG. In the case of the endless belt type polishing member 202, it is in a linear motion.

  The foreign substance adhesion position indicates the position itself where the foreign substance on the surface of the polishing member is adhered. For example, in the rotary polishing member 200 shown in FIG. 1A, when the reference coordinates (polar coordinates in the figure) fixed on the surface of the polishing member 200 are taken, the polishing member 200 to which the foreign matter F is attached is taken. The coordinates (R1, θ) on the surface are the foreign matter adhesion position. In the belt-type polishing member 202 shown in FIG. 1B, when the reference coordinates fixed on the surface of the polishing member 202 are taken, the coordinates (L1) to which the foreign matter F on the surface of the polishing member 202 is attached. , H) is a foreign matter adhesion position. The reference coordinates rotate or linearly move with the polishing member surface.

  The foreign matter adhesion range indicates a range in which foreign matter on the surface of the polishing member may be attached when the polishing member is stationary. Therefore, in the case of the rotary polishing member 200 shown in FIG. 1A, the foreign matter adhesion range is, for example, the position of the radius R1 from the rotation center of the polishing member 200 (the position θ in the circumferential direction is not specified), Alternatively, it can be expressed as a range from radius R2 to radius R3 (R2 ≠ R3). In the case of the belt-type polishing member 202 shown in FIG. 1B, the foreign matter adhesion range is a distance L1 from the end of the belt (the position H in the belt moving direction is not specified) or a distance L2. The distance L3 can be expressed as a range (L2 ≠ L3).

  Next, a description will be given of an adhesion region specifying unit that detects foreign matter on the surface of the polishing member by the detection unit and specifies a foreign matter attachment position or a foreign matter attachment range to be subjected to cleaning of the polishing member surface. The adhesion area specifying unit equipped with a foreign substance detection unit using a contact method detects adhesion of foreign matter on the polishing member surface by bringing the detection unit into contact with the polishing member, such as a pressure sensor or a displacement sensor that is in contact with the polishing member surface. Then, the foreign material adhesion position or the foreign material adhesion range on the surface of the polishing member is specified. The displacement sensor is, for example, a commercially available contact displacement sensor, or a displacement sensor including a detection piece that is brought into contact with the polishing member and a reading mechanism that reads the displacement. As the reading mechanism, a commercially available contact displacement sensor or non-contact displacement sensor can be used.

  For example, as illustrated in FIG. 2, an adhesion region specifying unit 206 using a plurality of pressure sensors 204 installed so as to be in contact with the surface of the rotary polishing member 200 will be described. As shown in FIG. 2A, a plurality of pressure sensors (detection units) 204 for detecting foreign matter attached to the surface of the polishing member 200 are arranged along a radius centered on the rotation center of the polishing member 200. The pressure detection surface is disposed in contact with the surface of the polishing member 200. The polishing member 200 rotates around its rotation center. The pressure sensor 204 is fixed at a fixed position without changing its position. As a result, the pressure sensor 204 and the polishing member 200 move relative to each other. Each pressure sensor 204 in contact with the polishing member 200 of each pressure sensor 204 draws an annular locus having a certain width with respect to the surface of the polishing member 200.

  In order to thoroughly check the presence or absence of foreign matter on the surface of the polishing member 200 and the range where foreign matter should be avoided, the pressure sensor 204 is disposed so that these circular trajectories partially overlap. It is preferable that at least the surface of the polishing member 200 that is in a range that may be in contact with the object to be polished 210 such as a semiconductor wafer held by the polishing head 208 is rotated with the rotation of the polishing member 200. The pressure sensor 204 is disposed so as to be in contact with the pressure detection surface of the pressure sensor 204 without leaving any excess.

  Therefore, the position where the pressure sensor 204 is disposed only needs to satisfy the above-described requirements. Therefore, the pressure sensor 204 is not limited to be disposed along one radius as shown in FIG. You may arrange | position along a radius each at three places equally 120 degrees with respect to the center. In this case, a foreign object can be detected quickly (that is, detected while the polishing member 200 rotates 120 °), but a relatively large number of pressure sensors are required. As another arrangement method of the pressure sensor, for example, the individual pressure sensors are arranged at different circumferential positions as viewed from the rotation center without following the radius centered on the rotation center of the polishing member. In other words, the intended purpose can be achieved even if they are not on the same radial line.

  As shown in FIG. 2B, each pressure sensor 204 is provided with a wiring 214 so that each read pressure signal can be transmitted to, for example, a data processing apparatus including a computer 212. . Note that the transmission of the pressure signal is not limited to transmission using wiring, but may be performed using a wireless transmission device.

  In the above description, for example, a rotating type polishing member 200 shown in FIG. 1A is used as the polishing member. However, as the polishing member, a belt type polishing member shown in FIG. The same is true when 202 is used. For example, with respect to the arrangement positions of the plurality of pressure sensors when the belt-type polishing member 202 is used, it is arranged in a direction perpendicular to the belt movement direction and in parallel with the belt surface. Or may be arranged as a plurality of rows. Alternatively, the belts may be arranged apart from each other without forming a row in a direction orthogonal to the belt movement direction. What is necessary is that the surface of the belt-type polishing member 202 to be detected by the foreign matter should be in contact with the pressure detection surface of the pressure sensor without any excess, in other words, be sure to be in contact with the locus formed by the pressure detection surface. A pressure sensor is provided.

  Next, a method for detecting the foreign matter F attached to the surface of the polishing member 200 with the pressure sensor 204 will be described. If the pressure sensor 204 is installed as shown in FIG. 2A, the foreign matter F adhering to the surface of the polishing member 200 protrudes from the surface of the polishing member 200 as shown in FIG. Therefore, when the foreign matter F adhering to the surface of the polishing member 200 passes between the surface of the polishing member 200 and the pressure sensor 204, as shown in FIG. It fluctuates and appears as peak P. Therefore, the adhesion of the foreign substance F to the surface of the polishing member 200 can be detected by monitoring the read pressure signal of the pressure sensor 204 with a computer or the like for controlling the polishing apparatus.

Further, the foreign matter adhesion range of the polishing member 200 is specified from the position of the pressure sensor 204 that detects the foreign matter F among the plurality of pressure sensors 204 or the measurement range of the surface of the polishing member 200 that the pressure sensor 204 shares. can do. Further, if the reference coordinates are set on the surface of the polishing member 200 and the time history of the movement of the reference coordinates by the rotational motion or the linear motion and the detection time are synchronized with the computer 212 or the like, for example, the foreign matter adhesion position of the polishing member 200 Can be specified. In addition, by using a pressure distribution measurement device (tactile sensor) with high spatial resolution as the pressure sensor 204, the foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member 200 can be specified with high accuracy.
FIG. 2A shows a state in which the polishing object 210 is being polished by supplying the polishing aid 218 from the nozzle 216 to the surface of the polishing member 200.

  Next, as shown in FIG. 3, as a detection unit, an adhesion region specifying unit 226 using a plurality of displacement sensors 224 provided with a detection piece 220 brought into contact with the polishing member 200 and a displacement reading mechanism 222 that reads the displacement thereof. explain.

  The displacement sensor (detection unit) 224 used in the adhesion region specifying unit 226 shown in FIG. 3 includes, for example, a detection piece 220, a displacement reading mechanism 222 arranged to read the displacement of the detection piece 220, and a displacement reading. A holding unit 228 that holds the mechanism 222 in a certain space so as not to fluctuate is provided. The detection piece 220 is configured such that when the foreign matter F protrudes from the surface of the polishing member 200 and the foreign matter F contacts the detection piece 220 due to the movement of the polishing member 200, the position of the detection piece 220 changes. ing. Therefore, when the foreign substance F exists on the surface of the polishing member 200, the relative position between the displacement reading mechanism 222 and the detection piece 220 changes. Therefore, as shown in FIG. 3C, the displacement reading mechanism 222 can transmit a displacement signal having a peak P.

  As the displacement reading mechanism 222, a general contact displacement sensor or a non-contact displacement sensor can be used. The presence of the foreign matter F on the polishing member 200 is first replaced with a change in the position of the detection piece 220, which is detected by, for example, a displacement reading mechanism 222 using a general non-contact displacement sensor, and a displacement signal is generated. Is recognized by the computer 212, for example.

  Here, as the object to be polished 210 is polished, the detection piece 220 is also polished and worn little by little. Therefore, the displacement of the detection piece 220 read by the displacement reading mechanism 222 changes with time even without the foreign matter F. Therefore, a means for canceling the change in the relative position between the displacement reading mechanism 222 and the detection piece 220 due to wear of the detection piece 220 is required. As such means, there are a signal filter that applies a high-pass filter, a differential filter, etc. to the displacement signal of the displacement reading mechanism, and a means that cancels the change in the relative position using the wear rate of the detection piece that has been obtained in advance.

It is preferable to use a material that is difficult to be polished for the detection piece 220. Examples of such materials include ceramic materials such as zirconia and alumina, and engineering plastic materials such as epoxy (EP) resin, phenol (PF) resin, and polyphenylene sulfide (PPS) resin.
Although the displacement sensor provided with the detection piece 220 and the displacement reading mechanism 222 has been described as the displacement sensor 224 here, a general contact displacement sensor may be used.

  In the example shown in FIG. 3, only the pressure sensor 204 in FIG. 2 is replaced with the displacement sensor 224, and the basic idea regarding the detection of the foreign matter F is the same as that of the pressure sensor 204. That is, FIG. 3A discloses an example using the rotary polishing member 200 and corresponding to FIG. 2A. Here, the plurality of displacement sensors 224 for detecting the foreign matter F adhering to the surface of the polishing member 200 has a detection piece 220 on the surface of the polishing member 200 along a radius centered on the rotation center of the polishing member 200. It is arranged to touch. The polishing member 200 rotates around its rotation center. The displacement reading mechanism 222 of the displacement sensor 224 is fixed at a fixed position so as not to change its position, for example, by the holding unit 228.

  The detection piece 220 of the displacement sensor 224 is held by a holding unit 228 so as to be movable, for example. That is, among the displacement sensors 224, the positions of the holding unit 228 and the displacement reading mechanism 222 are fixed, and only the detection piece 220 is movable. The polishing member 200 moves relative to the displacement sensor 224. To do. And the locus | trajectory in the surface of the polishing member 200 of the part which the detection piece 220 of each displacement sensor 224 touches the surface of the polishing member 200 becomes an annular | circular shape with a fixed width | variety, respectively. In order to thoroughly check the presence or absence of foreign matter on the surface of the polishing member 200 in a range where foreign matter should be avoided, the displacement sensor 224 may be disposed so that these circular trajectories partially overlap. Preferably, at least the surface of the polishing member 200, for example, in a range where it is likely to come into contact with the object to be polished 210 held by the polishing head 208, is always displaced as the polishing member 200 rotates. A displacement sensor 224 is disposed in contact with the detection piece 220 of the sensor 224.

  Therefore, since the disposition position of the displacement sensor 224 only needs to satisfy the above requirements, it is not limited to disposition along one radius as shown in FIG. You may arrange | position along a radius each at two places equally 180 degrees with respect to a rotation center. In this case, a foreign object can be detected quickly (that is, detected while the polishing member rotates 180 °), but a relatively large number of displacement sensors are required. As another arrangement method of the displacement sensor, for example, the individual displacement sensors are arranged at different circumferential positions as viewed from the rotation center without following the radius centered on the rotation center of the polishing member. However, the intended purpose can be achieved even if they are not on the same radial straight line.

  As shown in FIG. 3B, each displacement sensor 224 is provided with a wiring 214 so that a read displacement signal can be transmitted to a data processing device configured with, for example, a computer 212.

  The above example describes the case where the rotating polishing member 200 shown in FIG. 1A is used as the polishing member, for example, but the belt type shown in FIG. 1B is used as the polishing member. The same applies when the polishing member 202 is used. In other words, when the belt-type polishing member 202 is used, it is necessary to ensure that the surface of the belt-type polishing member 202 that is a foreign object detection target is not in contact with the locus formed by the detection piece of the displacement sensor. Displacement sensor is provided.

  Next, a method for detecting the foreign matter F attached to the surface of the polishing member 200 with the displacement sensor 224 will be described. If the displacement sensor 224 is installed as shown in FIG. 3A, the foreign matter F adhering to the surface of the polishing member 200 protrudes from the surface of the polishing member 200 as shown in FIG. Therefore, as shown in FIG. 3C, when the foreign matter F adhering to the surface of the polishing member 200 passes between the surface of the polishing member 200 and the detection piece 220, the read displacement signal of the displacement sensor 224 fluctuates. And have a peak P. Therefore, the adhesion of the foreign matter F on the surface of the polishing member 200 can be detected by monitoring the read displacement signal of the displacement sensor 224 with a computer or the like for controlling the polishing apparatus. In addition, the foreign matter adhesion range of the polishing member 200 can be specified from the position of the displacement sensor 224 that detects foreign matter or the detection range of the detection piece 220 among the plurality of displacement sensors 224. Furthermore, if the reference coordinates are set on the surface of the polishing member 200 and the time history of the movement of the reference coordinates by the rotational motion or the linear motion is synchronized with the detection time by the computer 212 or the like, for example, the foreign matter adhesion position of the polishing member 200 is specified can do.

  Specification of the foreign material adhesion position or foreign material adhesion range of the polishing member by the adhesion region specifying unit provided with the foreign material detection unit by the contact method described above is performed before polishing, during polishing, after polishing, or after dressing of the polishing member, etc. This can be done when the polishing member is moving. Since foreign matter adhesion can be detected even during polishing, foreign matter adhesion can be immediately detected.

  Next, a description will be given of an adhesion region specifying unit that detects a foreign matter on the surface of the polishing member by a non-contact detection unit and specifies a foreign matter attachment position or a foreign matter attachment range to be subjected to cleaning of the polishing member surface. The adhesion area specifying unit having a foreign matter detection unit using a non-contact method detects adhesion of foreign matter on the surface of the polishing member without contacting the polishing member, for example, by photographing the surface of the polishing member and analyzing the image. Then, the foreign material adhesion position or the foreign material adhesion range on the surface of the polishing member is specified.

  For example, with regard to an adhesion region specifying unit provided with an imaging device as a detection unit that images the surface of the polishing member and an arithmetic unit that performs image analysis of the captured image, the configuration will be described first, and then the adhesion region specification unit will be described. The image analysis used will be described.

  For example, as shown in FIG. 4, a photographing device (detecting unit) 230 is installed at a position where the surface of the polishing member 200 above the polishing member 200 can be photographed. The photographing device 230 may be a moving image photographing device or a still image photographing device, and may be an analog photographing device or a digital photographing device. Since the photographed image is analyzed by the arithmetic unit 232 as described below, in order to facilitate image analysis, the photographing device 230 is preferably a digital still image photographing device using a CCD camera or the like.

The adhesion region specifying unit 234 includes an arithmetic device 232 for performing image analysis on a photographed image. An image photographed by the photographing device 230 is transmitted, for example, as image data to the arithmetic device 232 through the wiring 233 and subjected to image analysis. As the arithmetic device 232, a general computer capable of executing image analysis using image analysis software or an auxiliary image analysis circuit, a dedicated image analysis computer, a digital image analysis circuit, an analog image analysis circuit, or the like can be used. . Further, the arithmetic device 232 may have a control function of the photographing device 230.
In this example, an image is an analog electrical signal converted from an analog image, digital image data, analog image, or digital image data.

  Next, image analysis by the adhesion region specifying unit 234 will be described. The surface of the polishing member 200 on which the object to be polished is polished is divided into an appropriate number of sections 236, and includes a certain section 236, and preferably includes a peripheral portion of the section 236 in the imaging range 238. Images are sequentially taken for each section 236 on the surface of the member 200. The arithmetic device 232 performs image conversion for correction on the photographed image, and performs feature extraction from the image converted image. Here, the image conversion for correction includes spatial filters such as noise removal, distortion correction, blur correction, sharpening (sharpening), image enhancement, spectrum conversion, Walsh conversion, wavelet conversion, normalization, etc. It is. The feature extraction includes edge extraction, line extraction, contour extraction, color extraction, density extraction, texture extraction, and the like.

  Thereafter, image recognition is performed by the arithmetic device 232 to determine whether or not foreign matter is attached to the surface of the polishing member 200. Here, the image recognition includes pattern recognition such as Nearest Neighbor Method, Bayes identification rule, dynamic programming matching (DP matching), Hidden Markov Model. In this example, performing at least one of image conversion, feature extraction, and image recognition is called image analysis. Thereby, it is possible to detect whether or not foreign matter is attached to the surface of the polishing member 200.

  In this example, the surface of the polishing member 200 is divided into a plurality of sections 236 and the shooting range 238 is sequentially shot. However, the entire polishing member 200 may be shot at once, and the number of the sections 236 may be taken. Is not particularly limited. Further, the adhesion position or adhesion range of the foreign substance F on the surface of the polishing member 200 can be specified as the position or range determined as having a foreign substance by image recognition. In order to specify the foreign matter adhesion position or the foreign matter adhesion range on the surface of the polishing member 200, as in the case of the contact method described above, the reference coordinates are set on the surface of the polishing member and rotated by a computer or the like for controlling the polishing apparatus. You may synchronize the time history and detection time of the movement of the reference coordinates by movement or linear movement.

Here, it is convenient to use a CCD camera as the photographing device 230. When a CCD camera is used, image analysis can be performed by a digital arithmetic unit 232. Needless to say, an analog camera can be used as the photographing device 230, and a photographing signal can be A / D converted and image analysis can be performed by the digital arithmetic device 232. The same applies to other imaging apparatuses.
Further, as the arithmetic device 232, a dedicated arithmetic device may be used for the adhesion region specifying unit 234, or a computer for controlling the polishing device may be used.

  When polishing using an opaque polishing aid, foreign matter on the surface of the polishing member 200 is detected by the adhesion region specifying unit 234 adopting the non-contact method described above during polishing of the polishing member or after dressing. It is desirable to carry out when almost no polishing aid remains on the surface of the member. In the example shown in FIG. 4, the foreign matter F on the surface of the polishing member 200 is detected while dressing the polishing member 200 with the dresser 244 while flowing pure water 242 from the nozzle 240 to the surface of the polishing member 200. . During the supply of the polishing aid or when a large amount of polishing aid remains on the surface of the polishing member 200, the surface of the polishing member 200 is covered with an opaque polishing aid, making it difficult to detect foreign matter.

  Moreover, the detection of the foreign matter on the surface of the polishing member 200 by the adhesion region specifying unit 234 adopting the non-contact method can be performed regardless of whether the polishing member 200 is moving. When the polishing member 200 is in motion, the section 236 moves in accordance with the movement of the polishing member 200, so that the photographing timing is synchronized with the movement of the polishing member 200. In addition, when the polishing member 200 is not moving, the photographing device 230 is moved so that the surface of the polishing member 200 on the object to be polished is completely photographed. As described above, the entire polishing member 200 may be photographed at once.

  In the above, the adhesion area | region specific part which has a detection part was demonstrated. However, the attachment region specifying unit does not necessarily include a detection unit. For example, information on a position or range where a foreign object is likely to adhere is obtained by simulation using a computer, and this information is not provided with a detection unit. The input may be input to the attached region specifying unit, or the attached region specifying unit itself may have a simulation function. Alternatively, the position or range information specified by the attached region specifying unit may be stored, and the attached region specifying unit may specify the position or range based on the past stored data. When these adhesion region specifying parts are used, it is not a requirement to detect foreign matter for the currently used polishing member.

  Next, a description will be given of the adhesion region specifying part by image analysis when diagnosing the polished surface (polished surface) of the polishing object. The adhesion area identification part by image analysis captures the polished surface of the polishing object, analyzes the image, detects scratches on the surface, and indirectly identifies the foreign substance adhesion position or foreign substance adhesion range on the polishing member surface. To do. For example, using a photographing device that photographs the polished surface (polished surface) of the object to be polished as the detection unit, and specifying an adhesion region that includes an arithmetic device (diagnostic device or image analyzing device) that analyzes the photographed image First, the configuration of the portion will be described, and then image analysis by the attached region specifying portion will be described.

  For example, as shown in FIG. 5, an imaging device (detection unit) 250 is installed at a position where the polished surface (polishing surface) 210a of the polishing object 210 such as a semiconductor wafer held on the holding table 246 can be imaged. Has been. Here, the photographing device 250 may be a moving image photographing device or a still image photographing device, and may be an analog photographing device or a digital photographing device. The photographed image is subjected to image analysis by an arithmetic device (diagnosis device or image analysis device) 252 as described below. Therefore, in order to facilitate image analysis, the photographing device 250 is a digital system using a CCD camera or the like. The still image photographing apparatus is preferable.

The adhesion area specifying unit 254 includes an arithmetic unit 252 for performing image analysis on a photographed image. An image photographed by the photographing device 250 is transmitted, for example, as image data to the arithmetic device 252 through the wiring 253 and subjected to image analysis. The arithmetic device 252 may be a general computer that can execute image analysis using image analysis software or an auxiliary image analysis circuit, a computer dedicated to image analysis, a digital image analysis circuit, an analog image analysis circuit, or the like. . Further, the arithmetic device 252 may have a control function of the photographing device 250.
In this example, an image is an analog electric signal converted from an analog image, digital image data, analog image, or digital image data.

  Next, image analysis by the adhesion region specifying unit 254 will be described. An imaging apparatus in which a polished surface (polishing surface) 210a of the object to be polished 210 is divided into an appropriate number of sections 256 and includes a certain section 256, and preferably a peripheral portion of the section 256 is also included in the shooting range 258. At 250, the polished surface 210a of the object to be polished 210 is sequentially photographed for each section 256. The arithmetic device 252 performs image conversion for correction on the photographed image, and performs feature extraction from the image converted image. Here, the image conversion for correction includes spatial filters such as noise removal, distortion correction, blur correction, sharpening (sharpening), image enhancement, spectrum conversion, Walsh conversion, wavelet conversion, normalization, etc. It is. The feature extraction includes edge extraction, line extraction, contour extraction, color extraction, density extraction, texture extraction, and the like.

  Thereafter, by performing image recognition with an arithmetic device (diagnosis device or image analysis device) 252, the scratch 210 b generated on the polished surface 210 a of the polishing object 210 is detected (extracted). When there is a scratch on the polished surface 210a of the object to be polished 210, foreign matter is adhered to the surface of the polishing member. Here, the image recognition includes pattern recognition such as Nearest Neighbor Method, Bayes identification rule, dynamic programming matching (DP matching), Hidden Markov Model. In this example, performing at least one of image conversion, feature extraction, and image recognition is called image analysis.

By using this adhesion region specifying part 254, it is possible to indirectly detect the adhesion of foreign matter to the surface of the polishing member. At that time, if the width, length, depth, and the like of the scratch are determined by the arithmetic device 252, it can be checked whether or not it is a fatal defect. When the scratch is a fatal defect, it is possible to take measures such as immediately stopping the polishing and cleaning the surface of the polishing member. If the scratch is not a fatal defect, polishing can be continued as it is. Therefore, it is possible to suppress the yield reduction without reducing the polishing throughput as much as possible.
Here, as the calculation device 252, a dedicated calculation device may be used for the adhesion region specifying unit 254, or a computer for controlling the polishing device may be used.

  When the object to be polished is a semiconductor wafer, various wafer defect inspection devices and wafer foreign matter inspection devices sold by semiconductor device inspection device manufacturers can be used to detect scratches and determine whether scratches are fatal defects. it can. Accordingly, if the adhesion area specifying unit 254 is used to detect the scratch 210b of the surface (polishing surface) 210a of the object to be polished 210 and the above-described commercially available defect inspection apparatus is used in combination, the throughput is maintained at a suitable value. it can.

  Next, a method for specifying a foreign matter adhesion position or a foreign matter adhesion range by image analysis when diagnosing the polished surface (polished surface) 210a of the object to be polished 210 will be described. The method for identifying the foreign matter adhesion position or foreign matter adhesion range by image analysis is to photograph and analyze the image of the surface (polished surface) 210a of the polished object 210 after polishing, and from the scratch 210b of the surface 210a, the surface of the polishing member surface. This is a method for specifying a foreign matter adhesion position or a foreign matter adhesion range.

  Here, the detection of scratches on the surface (polishing surface) 210a of the object to be polished 210 is performed by, for example, the above-described adhesion region specifying unit 254. The adhesion area specifying unit 254 includes an arithmetic unit 252 that analyzes an image of the scratch detected by the imaging device (detecting unit) 250.

  One method for specifying the foreign matter adhesion position or foreign matter adhesion range of the polishing member is, as disclosed in Patent Document 11, by calculating the center of curvature circle or radius of curvature at one point on the scratch and the geometric parameters of the polishing apparatus. It is a method of specifying from the formulated scratch trajectory. Here, the geometric parameter of the polishing apparatus is a parameter determined by the positional relationship of each element of the apparatus, such as the distance between the rotation center of the polishing member and the rotation center of the polishing object. The calculation device provided in the adhesion region specifying unit calculates the center of curvature circle and the radius of curvature from the scratch by image analysis, and calculates from the formulated scratch trajectory to specify the adhesion position or adhesion range of the foreign matter.

  According to this method, the foreign material adhesion position or the foreign material adhesion range of the polishing member can be obtained with high accuracy. However, when the object to be polished swings on the polishing member, the formulation of the scratch trajectory and the calculation method for specifying the foreign matter adhesion position or the foreign matter adhesion range from the formulated scratch trajectory become complicated.

  Therefore, a method for specifying a foreign substance adhesion position or a foreign substance adhesion range using the adhesion area identification unit 254 according to this example will be described below. According to this method, even if a complicated polishing recipe is set, the foreign matter adhesion position or the foreign matter adhesion range on the surface of the polishing member can be easily specified with high accuracy, which is extremely useful.

  First, when a polishing object is polished with a polishing member to which foreign matter has adhered, the scratch pattern generated on the polished surface (polishing surface) after polishing is calculated, for example, for several foreign matter attachment positions or foreign matter attachment ranges. It is calculated by the apparatus and stored as a standard pattern appearing on the polishing surface of the object to be polished in a storage device capable of reading programs and / or data. Next, the scratch pattern (detection pattern) of the polished surface (polishing surface) of the polishing object actually detected by the adhesion region specifying unit 254 and the standard pattern are compared by the arithmetic unit 252, and polishing is performed based on the degree of approximation. The foreign substance adhesion position or foreign substance adhesion range of the member is specified. The comparison by the arithmetic device 252 includes image recognition.

  Here, the standard pattern includes a standard pattern created experimentally and a standard pattern created by simulation. A method for creating a standard pattern experimentally is, for example, as follows. First, an object to be polished is actually polished with a polishing member to which foreign substances or substitutes for foreign substances are artificially attached. Next, the scratch formed by polishing is detected by image analysis by the adhesion region specifying unit 254. A desired pattern is created as computer-readable image data from the detected scratch. When image data is adopted as the standard pattern, the detected scratch image data is the standard pattern.

  A method of creating a standard pattern by simulation is as follows. First, the trajectory of the surface of the object to be polished (surface to be polished) of the foreign matter fixed on the surface of the polishing member is calculated using the geometric parameters of the polishing apparatus, the polishing conditions, the foreign matter attachment position or the foreign matter attachment range. A desired pattern is created as computer-readable data from the calculated locus. When image data is adopted as a standard pattern, image data obtained by converting created pattern data into image data is a standard pattern.

  Therefore, the image data of the scratch detected by the photographing device 250 is used as a detection pattern, and the detection pattern and the standard pattern are compared by image recognition using the arithmetic unit 252. Or the foreign substance adhesion range can be specified.

  Here, the geometric parameter is a parameter determined by the positional relationship of each element of the apparatus such as the distance between the rotation center of the polishing member and the rotation center of the polishing object, and the polishing condition is the rotation speed of the polishing member ( Polishing member moving speed), polishing object rotation speed, polishing object rocking speed, polishing object rocking range, and the like. The polishing condition is a known value because it is normally input to the polishing apparatus as a polishing recipe before polishing. Even if the polishing conditions are complicated, it is easy to create a standard pattern according to the adhesion position from this known polishing recipe. Therefore, after inputting a polishing recipe to the polishing apparatus, a standard pattern can be created by performing a simulation with an arithmetic device or a computer provided in the polishing apparatus.

  Therefore, even if a complicated polishing recipe is set, the foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member can be specified with high accuracy. Since the detection pattern is compared with the standard pattern and the foreign matter adhesion position or the foreign matter adhesion range on the polishing member surface is specified, the accuracy can be increased by increasing the number of standard patterns as necessary. Note that image recognition includes pattern recognition such as Nearest Neighbor Method, Bayesian identification rules, dynamic programming matching (DP matching), and Hidden Markov Model.

  Here, in the above description, the example of the image data is given as the standard pattern. However, the radial density distribution and the circumferential density distribution of the scratch, and the presence / absence of the scratch at a specific position on the surface to be polished are obtained from the scratch. Various data can be used as the standard pattern. When such a standard pattern is used, the foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member can be specified without performing image recognition.

  For example, when describing a circular polishing target surface, a method for specifying a scratch polishing surface radial direction density distribution or a circumferential direction density distribution as a standard pattern is as follows. First, using the arithmetic unit 252, the polishing surface radial density distribution and the circumferential density distribution of the scratch are calculated from the scratch detected by the photographing apparatus 250 to obtain a detection pattern. Next, the calculation device 252 calculates the detection pattern and the characteristics of the distribution of the standard pattern previously stored as data, for example, the periodicity of the distribution of the scratch, the peak position (position where the scratch is concentrated), and the peak height. By comparing (scratch concentration, that is, density) or the like, the attachment position or the attachment range is specified.

  Here, when the distribution characteristics of the detection pattern and the standard pattern do not completely match, the calculation unit 252 selects the closest standard pattern and adopts its adhesion position or adhesion range, or some nearby standards. The average of the position or range of adhesion of the pattern or the maximum value of the distribution function is obtained and the result is used to specify the position or range of foreign matter adhesion on the polishing member surface. Therefore, the foreign matter attachment position or the foreign matter attachment range is not limited to one. The same applies to any other specific method.

  Here, as the calculation device 252, a dedicated calculation device may be used for the adhesion region specifying unit 254, or a computer for controlling the polishing device may be used.

  FIG. 6 is a plan view showing an arrangement configuration of each part of a chemical mechanical polishing apparatus mainly for polishing a semiconductor wafer according to an embodiment of the present invention. The chemical mechanical polishing apparatus shown in FIG. 6 includes four load / unload stages 22 on which a wafer cassette 21 for stocking a large number of semiconductor wafers (objects to be polished) is placed. The load / unload stage 22 may have a mechanism capable of moving up and down. A transfer robot 24 having two hands is disposed on the traveling mechanism 23 so that each wafer cassette 21 on the load / unload stage 22 can be reached.

  An adhesion area specifying unit 120 shown in FIG. 5 is provided at a position where the transfer robot 24 can reach, detecting foreign matter attached to the polishing pad (polishing member) and specifying the foreign matter attachment range of the polishing pad. In this example, the adhesion region specifying unit 120 includes an adhesion region specifying unit 254 including an imaging device 250 and a calculation device (diagnosis device or image analysis device) 252 shown in FIG. By diagnosing the surface (polishing surface), foreign matter on the polishing pad is detected and the foreign matter adhesion range is specified. Here, it is preferable that the adhesion region specifying unit 120 is configured to be able to diagnose a plurality of semiconductor wafers in parallel. Thereby, it can grind | polish, without reducing the processing capacity (throughput) of a grinding | polishing apparatus.

  Of the two hands in the transfer robot 24, the lower hand is used only when a semiconductor wafer is received from the wafer cassette 21. Further, the upper hand is used when a semiconductor wafer is taken in and out from the adhesion area specifying unit 120 and when the semiconductor wafer is returned to the wafer cassette 21. This is an arrangement in which the clean semiconductor wafer after cleaning is placed on the upper side so that the semiconductor wafer is not further contaminated. The lower hand is a suction-type hand that vacuum-sucks a semiconductor wafer, and the upper hand is a drop-type hand that holds the peripheral edge of the semiconductor wafer. The suction-type hand accurately conveys regardless of the deviation of the semiconductor wafer in the wafer cassette 21, and the drop-type hand does not collect dust like vacuum suction, so that the cleanness of the back surface of the semiconductor wafer is maintained. Semiconductor wafers can be transferred.

  Two cleaning machines 25 and 26 are arranged on the side opposite to the wafer cassette 21 with the traveling mechanism 23 of the transfer robot 24 as the axis of symmetry. Each of the cleaning machines 25 and 26 is disposed at a position where the hand of the transfer robot 24 can reach. Further, a wafer station 70 having four semiconductor wafer mounting tables 27, 28, 29, and 30 is disposed between the two cleaning machines 25 and 26 at a position where the robot 24 can reach. The cleaning machines 25 and 26 have a spin dry function of drying a semiconductor wafer by rotating it at high speed, and can thereby cope with two-stage cleaning and three-stage cleaning of the semiconductor wafer without replacing the modules.

  In order to divide the cleanliness between the area B where the cleaning machines 25 and 26 and the mounting tables 27, 28, 29 and 30 are arranged and the area A where the wafer cassette 21, the adhesion area specifying unit 120 and the transfer robot 24 are arranged. A partition wall 84 is disposed on the partition wall 84, and a shutter 31 is provided at the opening of the partition wall 84 to transport the semiconductor wafer between the regions A and B. A transfer robot 80 having two hands is arranged at a position where it can reach the cleaning machine 25 and the three mounting tables 27, 29, and 30, and can reach the cleaning machine 26 and the three mounting tables 28, 29, and 30. A transfer robot 81 having two hands is arranged at a proper position.

  The mounting table 27 is used to transfer semiconductor wafers between the transfer robot 24 and the transfer robot 80, and includes a semiconductor wafer presence / absence detection sensor 91. The mounting table 28 is used to deliver a semiconductor wafer between the transfer robot 24 and the transfer robot 81, and includes a semiconductor wafer presence / absence detection sensor 92. The mounting table 29 is used to transfer a semiconductor wafer from the transfer robot 81 to the transfer robot 80, and includes a sensor 93 for detecting the presence / absence of a semiconductor wafer and a rinse nozzle 95 for preventing or cleaning the semiconductor wafer. .

  The mounting table 30 is used to transfer a semiconductor wafer from the transfer robot 80 to the transfer robot 81, and includes a semiconductor wafer presence / absence detection sensor 94 and a rinse nozzle 96 for preventing or cleaning the semiconductor wafer. . The mounting tables 29 and 30 are arranged in a common waterproof cover, and a shutter 97 is provided in a cover opening for transportation. The mounting table 29 is on the mounting table 30, and the cleaned semiconductor wafer is placed on the mounting table 29, and the semiconductor wafer before cleaning is placed on the mounting table 30, thereby preventing contamination due to the rinsing water falling. In FIG. 6, the sensors 91, 92, 93, 94, the rinse nozzles 95, 96, and the shutter 97 are schematically shown, and the positions and shapes are not shown accurately.

  The upper hands of the transfer robots 80 and 81 are used to transfer a semiconductor wafer once cleaned to the mounting table of the cleaning machines 25 and 26 or the wafer station 70, and the lower hand has been cleaned once. Used to transport non-semiconductor wafers and unpolished semiconductor wafers to a reversing machine. By putting the semiconductor wafer into and out of the reversing machine with the lower hand, the upper hand is not contaminated by the rinsing water drops from the upper wall of the reversing machine. A cleaning machine 82 is arranged at a position where the hand of the transfer robot 80 can reach so as to be adjacent to the cleaning machine 25. In addition, a washing machine 83 is arranged at a position where the hand of the transfer robot 81 can reach so as to be adjacent to the washing machine 26. The cleaning machines 25, 26, 82, 83, the mounting tables 27, 28, 29, 30 of the wafer station 70 and the transfer robots 80, 81 are all arranged in the region B and lower than the atmospheric pressure in the region A. It is adjusted to atmospheric pressure. The washing machines 82 and 83 are, for example, washing machines capable of performing double-sided washing.

  This chemical mechanical polishing apparatus has a housing 66 so as to surround each device, and the inside of the housing 66 includes a plurality of chambers (region A, region B) by a partition wall 84, a partition wall 85, a partition wall 86, a partition wall 87, and a partition wall 67. Is included). A polishing chamber separated from the region B by the partition wall 87 is formed, and the polishing chamber is further partitioned by a partition wall 67 into a region C as the first polishing portion and a region D as the second polishing portion. In each of the two regions C and D, two polishing tables and one top ring for holding one semiconductor wafer and polishing while pressing the semiconductor wafer against the polishing table are arranged. . That is, the polishing tables 54 and 56 are arranged in the area C, the polishing tables 55 and 57 are arranged in the area D, the top ring 52 is arranged in the area C, and the top ring 53 is arranged in the area D, respectively. Yes.

  Here, the polishing pad 10 (see FIG. 7) is attached to the uppermost surfaces of the polishing tables 54, 55, 56, 57 as a polishing member. Different types of polishing pads may be used depending on the purpose of polishing. A polishing liquid nozzle 60 for supplying a polishing abrasive liquid to the polishing table 54 in the region C and a dresser 58 for dressing the polishing table 54 are arranged. In addition, an adhesion region specifying unit 110 for detecting foreign matter attached to the polishing table 54 in the region C and specifying a foreign matter attachment range is disposed, and a cleaning unit 112 for cleaning the polishing table 54 is disposed. . A polishing liquid nozzle 61 for supplying a polishing polishing liquid to the polishing table 55 in the region D and a dresser 59 for dressing the polishing table 55 are arranged. In addition, an adhesion area specifying unit 111 for detecting foreign matter attached to the polishing table 55 in the area D and specifying a foreign substance attachment range is arranged, and a cleaning unit 113 for cleaning the polishing table 55 is arranged. . Further, a dresser 68 for dressing the polishing table 56 in the region C and a dresser 69 for dressing the polishing table 57 in the region D are arranged.

  In this example, the adhesion region specifying units 110 and 111 are configured by an adhesion region specifying unit 226 having a plurality of displacement sensors 224 shown in FIG. The attachment region specifying units 110 and 111 are configured by the attachment region specifying unit 206 having a plurality of pressure sensors 204 shown in FIG. 2, or the attachment region specifying unit having the photographing device 230 and the arithmetic device 232 shown in FIG. 234 may be used.

  Thereby, the adhesion region specifying units 110 and 111 can detect the adhesion of foreign matter on the polishing pad even during polishing, and can specify the foreign matter adhesion range on the polishing pad. The cleaning units 112 and 113 are cleaning units that clean the polishing pad by rubbing a rotating brush against the polishing pad. The cleaning units 112 and 113 have a mechanism for moving the brush to an arbitrary radius of the polishing pad. Therefore, if the brushes of the cleaning units 112 and 113 are fixed at a certain position while the polishing tables 54 and 55 are rotating, the range corresponding to the position of the polishing pad can be cleaned preferentially. Further, if the brushes of the cleaning units 112 and 113 are moved so as to swing between the center and the end of the polishing pad, the polishing pad can be cleaned evenly.

  Here, “intensive cleaning” means (1) cleaning for a long time compared to other positions or ranges, and (2) when rubbing with a brush, grindstone, PVA sponge scrub, etc. Rubbing with a pressure larger than the range, (3) When rubbing by rotating a brush, grindstone, PVA sponge scrub, etc., rubbing at a higher rotational speed than other positions or ranges, (4) Pure water or When washing away foreign substances by spraying a cleaning solution such as a chemical solution, the cleaning solution is sprayed and washed under conditions selected from among a large flow rate, high speed (high pressure), high concentration, and high temperature compared to other positions or ranges. (5 ) When sucking slurry, suck the slurry with higher suction than other positions or ranges. (6) When dissolving with a solution such as peroxosulfuric acid or hydrofluoric acid, move to other positions or ranges. compared It is dissolved at a high concentration or high temperature, to assist the washing with ultrasonic (7), washing with ultrasonic waves of a high output compared to other positions or range, and the like. The same applies to the following.

  Instead of the polishing tables 56 and 57, a wet type wafer film thickness measuring machine may be installed. In that case, immediately after polishing, the film thickness of the film on the surface of the semiconductor wafer can be measured with a wafer film thickness measuring device, and the film thickness on the surface of the semiconductor wafer can be increased or the measured value can be used to transfer to the next semiconductor wafer. It is also possible to control the polishing process.

  In order to transfer the semiconductor wafer between the polishing chamber and the region B, the reversing machines 99, 100, 101, 102 for turning the semiconductor wafer upside down to a position where the transfer robots 80, 81 and the top rings 52, 53 can reach. A rotary wafer station 98 is arranged. The reversing machines 99, 100, 101, 102 rotate with the rotation of the rotary wafer station 98.

  A method for delivering a semiconductor wafer between the polishing chamber and the region B will be described. The reversing machines 99, 100, 101, and 102 provided in the rotary wafer station 98 are, as shown in the figure, the reversing machines 99 and 100 on the area B side, the reversing machine 101 on the area C side, and the area D. Assume that the reversing machines 102 are arranged on the sides. The semiconductor wafer to be polished is transferred from the wafer station 70 to the reversing machine 99 arranged on the region B side of the rotary wafer station 98 by the transfer robot 80. Another semiconductor wafer is transferred from the wafer station 70 to the reversing machine 100 arranged on the region B side of the rotary wafer station 98 by the transfer robot 81.

  When the transfer robot 80 transfers the semiconductor wafer to the rotary wafer station 98, the shutter 45 provided in the partition wall 87 is opened, and the semiconductor wafer can be transferred between the region B and the polishing chamber. When the transfer robot 81 transfers the semiconductor wafer to the rotary wafer station 98, the shutter 46 provided in the partition wall 87 is opened, and the semiconductor wafer can be transferred between the region B and the polishing chamber.

  After the semiconductor wafer is transferred to the reversing machine 99 and another semiconductor wafer is transferred to the reversing machine 100, the rotary wafer station 98 rotates 180 degrees around the axis, and the reversing machine 99 is moved to the region D side. Is moved to the region C side. The semiconductor wafer moved to the region C side by the rotary wafer station 98 is transferred to the top ring 52 after the surface (surface) to be polished is inverted downward by the reversing machine 100. The semiconductor wafer moved to the region D side by the rotary wafer station 98 is transferred to the top ring 53 after the surface to be polished (front surface) is inverted downward by the reversing machine 99.

  The semiconductor wafer transferred to the top rings 52 and 53 is adsorbed by the vacuum adsorption mechanism of the top rings 52 and 53, and the semiconductor wafer is conveyed while being adsorbed to the polishing tables 54 and 55. Then, the semiconductor wafer is polished by a polishing pad attached on the polishing tables 54 and 55.

  FIG. 7 is a diagram schematically showing an example of a schematic cross section of a part of the top ring 52 and the polishing table 54 during polishing. The top ring 53 and the polishing table 55 have the same structure. As shown in FIG. 7, the top ring 52 that is a holding portion of the semiconductor wafer 2 that is the object to be polished includes the airbag 5 for pressing the semiconductor wafer 2 against the polishing member (polishing pad) 10 with a predetermined pressure, A support portion (retainer ring) 14 installed so as to surround the polishing object 2 and an airbag 6 for pressing the polishing pad 10 around the semiconductor wafer 2 with a predetermined support surface pressure by the retainer ring 14 are provided. Yes.

  In this embodiment, as shown in FIG. 7, the retainer ring 14 has an annular shape in plan view along the outer periphery of the semiconductor wafer 2 held by the top ring 52 with a slight gap, and has a rectangular cross section. It is composed of a single member. The lower surface of the retainer ring 14 forms a support surface that supports the protruding portion of the polishing pad 10 from the surface (surface to be polished) of the semiconductor wafer 2, and is a plane having substantially the same height throughout. The material of the retainer ring 14 is composed of, for example, a ceramic material such as zirconia or alumina, or an engineering plastic material such as epoxy (EP) resin, phenol (PF) resin, or polyphenylene sulfide (PPS) resin.

  The pressure for pressing the retainer ring 14 against the polishing pad 10 is adjusted by controlling the pressure of the airbag 6 by the pressure adjusting mechanism 108. Note that the support surface pressure may be adjusted by controlling the load from the shaft by the pressure adjusting mechanism 108 without providing the airbag 6. The airbag 5 may be one section as shown in the figure, or may be divided into a plurality of sections concentrically.

  The polishing table 54 includes a polishing surface plate 9 and a polishing pad 10. As shown in FIG. 7, the polishing pad 10 may be a single-layer pad or a multilayer pad having two or more layers. At the time of polishing, the top ring 52 rotates in the direction of arrow A about the axis while pressing the semiconductor wafer 2 against the polishing pad 10. Also, during polishing, the polishing table 54 also rotates in the direction of arrow B about its axis. At the time of polishing, the adhesion area specifying unit 110 detects the adhesion of foreign matter on the polishing pad 10.

  Returning to FIG. 6, in FIG. 6, the second polishing tables 56 and 57 described above are arranged at positions where the top rings 52 and 53 can reach each other. As a result, the semiconductor wafer can be finished and polished by the polishing pad for finishing attached to the second polishing tables 56 and 57 after the polishing by the first polishing tables 54 and 55 is completed. In the finishing table, perform pure water finishing while supplying pure water or a chemical solution that does not contain abrasive grains to a polishing pad such as SUBA400 or Polytex (both are names of polishing pads and manufactured by Rodel Nitta), or Polishing is performed by supplying slurry. During the polishing, the semiconductor wafer to be used for the next polishing may be transferred by the transfer robots 80 and 81 to the reversing machines 101 and 102 moved to the region B side.

  The polished semiconductor wafer is transferred to reversing machines 99 and 100 by the top rings 52 and 53, respectively. The semiconductor wafer transferred to the reversing machines 99 and 100 is reversed by the reversing machines 99 and 100 so that the polished surface (polished surface) faces upward, and then the rotary wafer station 98 rotates 180 degrees. , Move to the region B side. The semiconductor wafer moved to the region B side is transferred from the reversing machine 99 to the cleaning machine 82 or the wafer station 70 by the transfer robot 80. Further, another semiconductor wafer moved to the region B side is transferred from the reversing machine 100 to the cleaning machine 83 or the wafer station 70 by the transfer robot 81. Thereafter, through an appropriate cleaning process, the adhesion region specifying unit 120 diagnoses the presence or absence of scratches on the polished surface of the semiconductor wafer (polished surface), and stores it in the wafer cassette 21.

  After the polishing by the polishing tables 54 and 55 is completed, the polishing pad attached to the uppermost surface of the polishing tables 54 and 55 is dressed by the dressers 58 and 59. At the time of dressing, the abrasive nozzles 60 and 61 supply a cleaning liquid such as pure water to the polishing pad. By this dressing, the surface of the polishing pad is cleaned, sharpened, and the shape is corrected. In addition, if adhesion of foreign matter is not detected on the polishing pad by the adhesion region specifying units 110 and 111 and the adhesion region specifying unit 120, the intensive cleaning range of the polishing pad is set by the brushes of the cleaning units 112 and 113 in parallel with the dressing. Wash heavily. As described later, the important cleaning range is set in advance as a range in which foreign matter is likely to adhere, and thus, the important cleaning range of the polishing pad is carefully cleaned by the cleaning units 112 and 113, thereby polishing. Adherence of foreign matter to the pad can be prevented. Also during dressing, the adhesion area specifying units 110 and 111 detect the adhesion of foreign matter on the polishing pad, so that the adhesion range can be identified by detecting the adhesion of foreign matter on the polishing pad even during polishing. .

  When the adhesion area specifying units 110 and 111 detect foreign substances adhering to the polishing pad during polishing or dressing, the foreign substance adhesion range on the polishing pad can be specified as the radius range of the polishing pad. In this example, as the adhesion area specifying portions 110 and 111, an adhesion area specifying section 226 having a plurality of displacement sensors 224 shown in FIG. 3 is used, and a plurality of displacement sensors 224 are provided along the radial direction of the polishing pad. This is because it can be specified as a range corresponding to the detection range of the displacement sensor 224 that has detected a foreign object. When the foreign matter adhesion range is specified, the cleaning units 112 and 113 mainly clean the foreign matter adhesion range. Thereby, the foreign material adhering to the polishing pad can be efficiently removed. Note that if the adhesion area specifying portions 110 and 111 are always in contact with the polishing pad, the adhesion area specifying portions 110 and 111 may become a source of foreign matter. Therefore, during polishing of the semiconductor wafer, the adhesion region specifying portions 110 and 111 may be retracted to a retraction region (not shown). Further, during the retreat to the retreat area, the adhesion area specifying portions 110 and 111 may be cleaned by an unillustrated adhesion area specifying portion cleaning apparatus. In this way, it is possible to prevent the generation of foreign matters from the adhesion area specifying portions 110 and 111.

  In addition, in the adhesion area | region identification part 110,111, the foreign material which is poured by a slurry and washing | cleaning liquid and moves on a polishing pad may be detected besides the foreign material adhering to a polishing pad. For this reason, in the chemical mechanical polishing apparatus shown in FIG. 6, in order to detect adhesion of foreign matter on the polishing pad more accurately, the presence or absence of foreign matter is diagnosed by diagnosing the presence or absence of scratches on the polished surface (polishing surface) of the semiconductor wafer. An adhesion region specifying unit 120 that detects adhesion is provided. In this example, the adhesion area specifying unit 254 using the photographing apparatus 250 shown in FIG. 5 is used as the adhesion area specifying part 120. That is, the adhesion region specifying unit 120 analyzes the image of the polished surface (polished surface) of the semiconductor wafer imaged by the imaging device 250 (see FIG. 5) with the arithmetic device (diagnosis device or image analysis device) 252. Thus, the presence or absence of scratches on the surface is diagnosed. As a result of the image analysis, when it is determined that there is a scratch on the polished surface of the semiconductor wafer, the adhesion of foreign matter to the polishing pad is detected. Further, the foreign matter adhesion range on the polishing pad can be specified by pattern recognition of the photographed scratch image.

  As a standard pattern used for image recognition, FIG. 8 shows an example in which a scratch is simulated on the assumption that foreign matter has adhered to the radius R1 of the polishing pad. In this example, the semiconductor wafer rotation speed is 80 rpm and the polishing pad rotation speed is 90 rpm, and there is no oscillation of the semiconductor wafer during polishing. In this example, five standard patterns are illustrated with an interval of the radius R1 being 60 mm. That is, FIG. 8A shows a scratch pattern when foreign matter adheres on a radius on the polishing pad: R1 = 315 mm, and FIG. 8B shows a foreign matter on the radius: R1 = 255 mm on the polishing pad. FIG. 8C shows the scratch pattern when adhered, and FIG. 8D shows the scratch pattern when foreign matter adheres on the radius R1 = 195 mm on the polishing pad. FIG. 8D shows the radius R1 on the polishing pad. FIG. 8 (e) shows a scratch pattern when a foreign object adheres on a radius on the polishing pad: R1 = 75 mm. In practice, it is preferable to prepare a larger number of standard patterns with a smaller interval.

  By pattern recognition, several patterns close to the scratch pattern photographed from these standard patterns are selected, and the foreign matter adhesion range (pad radius range) on the polishing pad is specified from the pattern approximation degree. When the adhesion region specifying unit 120 determines that there is no scratch on the surface of the semiconductor wafer, it is not necessary to perform pattern recognition. When the adhesion area specifying unit 120 detects the adhesion of foreign matter on the polishing pad and identifies the foreign matter adhesion range, the cleaning parts 112 and 113 mainly clean the foreign matter adhesion range on the polishing pad. Thereby, the foreign material adhering to the polishing pad can be efficiently removed.

  Here, when the foreign matter adhesion range of the polishing pad specified by the adhesion region specification units 110 and 111 and the foreign matter adhesion range of the polishing pad specified by the adhesion region specification unit 120 overlap, the probability that the foreign matter has adhered to the polishing pad. And there is a high probability that foreign matter is attached to the specified foreign matter attachment range. In addition, if the foreign matter cannot be removed while polishing one semiconductor wafer and foreign matter is detected on multiple sheets, the foreign matter is attached even though the foreign matter attachment range of the polishing pad has been intensively cleaned. Polishing with the polishing table thus performed is temporarily stopped, and the cleaning unit 112, 113 can focus on the adhesion range to remove foreign matters. It can be known by the adhesion region specifying portions 110 and 111 that the foreign matter has been removed from the polishing pad.

  This chemical mechanical polishing apparatus can store and accumulate the foreign substance adhesion ranges identified by the adhesion area identification units 110 and 111 and the adhesion area identification unit 120 in a storage device installed in the control computer 130. Further, the control computer 130 calculates the adhesion probability based on the accumulated data of the specific range, so that it is possible to determine the range in which foreign matter is likely to adhere. By using the cleaning units 112 and 113 as a focus cleaning range when the foreign matter is likely to adhere, the cleaning units 112 and 113 can be used to effectively prevent the foreign matter from adhering to the polishing pad. In this chemical mechanical polishing apparatus, all processes such as transport, polishing, cleaning of semiconductor wafers, detection of adhesion of foreign matters to the polishing pad, and specification of the attachment position are controlled by the control computer 130.

  Here, a description will be given of a method for calculating the probability that foreign matter has adhered to the polishing pad 10 of the polishing table 54 from the accumulated data in a specific range specified by the adhesion region specifying unit 110. First, as shown in FIG. 9A, the sections 1 to 5 are defined that divide the polishing pad 10 of the polishing table 54 into five in the radial direction. Each section corresponds to the detection range of the five displacement sensors 224 of the adhesion region specifying unit 110. In addition, the part with which the detection range overlaps is made to respond | correspond to an inner division. Now, it is assumed that data in a specific range is accumulated as the adhesion frequency in the sections 1 to 5 as shown in FIG. 9B. The sticking probability in each section is the sticking probability shown in FIG. 9C because the sticking frequency of the section / total sticking frequency × 100%.

  Here, in a case where the priority cleaning range is a section having an adhesion probability of 30% or more, the sections 3 and 4 are the priority cleaning range. In the case where the intensive cleaning range of the polishing pad 10 is intensively cleaned by the cleaning unit 112, the polishing pad 10 is swung between the section 3 and the section 4 of the polishing pad 10 to clean the polishing pad 10. . In addition, when the priority cleaning range is a section with the highest adhesion probability, the section 3 of the polishing pad 10 is the priority cleaning range. In this case, it is not necessary to calculate the adhesion probability, and the section with the maximum adhesion frequency may be set as the priority cleaning range. In the case where the cleaning area 112 is used for intensive cleaning of the important cleaning range (section 3) of the polishing pad 10, the cleaning unit 112 is swung between the sections 3 of the polishing pad 10 for cleaning. If the area of the partition 3 of the polishing pad 10 can be cleaned even if the brush is large and does not oscillate, it is not necessary to oscillate the brush and the position of the brush may be fixed.

  As described above, the method for calculating the adhesion probability from the accumulated data in the specific range specified by the adhesion region specifying unit 110 for the polishing pad 10 of the polishing table 54 has been described. However, the adhesion region specifying unit 111 for the polishing pad of the polishing table 55 is described. The same applies to the method for calculating the adhesion probability from the specified specified range of accumulated data. Similarly, with respect to the method of calculating the adhesion probability from the accumulation data in the specific range specified by the adhesion area specifying unit 120, the division for dividing the polishing pad in the radial direction is defined, and the adhesion frequency of each division is accumulated in the storage device. Then, the adhesion probability may be calculated from the accumulated data.

Next, a control flow for polishing a semiconductor wafer as a polishing object with a polishing pad as a polishing member using the chemical mechanical polishing apparatus shown in FIG. 6 will be described. Here, for the sake of simplicity, another semiconductor wafer is processed until one semiconductor wafer exits the wafer cassette 21 and is polished by the polishing pad 10 of the polishing table 54, cleaned, and returned to the wafer cassette 21 again. An example will be described in which the process is not started. In practice, a plurality of semiconductor wafers are processed in parallel in consideration of throughput.
For example, the following information is stored in the storage device of the control computer 130.

A. Polishing apparatus control program A-1. Polishing main routine A-2. Polishing preparation end determination routine A-3. Dressing routine A-4. Polishing pad cleaning routine A-5. Semiconductor wafer cleaning routine A-6. Foreign matter adhesion monitoring routine by polishing pad diagnosis A-7. Foreign matter adhesion determination routine by polishing surface diagnosis A-8. Routine washing range calculation routine A-9. Semiconductor wafer transfer routine, etc.

B. Various conditions B-1. Semiconductor wafer transfer conditions B-2. Polishing conditions (polishing recipe)
B-2-1. Polishing pad rotation speed B-2-2. Semiconductor wafer (top ring) rotation speed B-2-3. Semiconductor wafer (top ring) rocking speed B-2-4. Swing range of semiconductor wafer (top ring) B-2-5. Polishing time B-2-6. Polishing pressure B-2-7. Slurry supply flow rate

B-3. Dressing conditions B-3-1. Polishing pad rotation speed B-3-2. Dresser rotation speed B-3-3. Dresser rocking speed B-3-4. Dresser swing range B-3-5. Dressing time B-3-6. Dressing pressure B-3-7. Cleaning liquid supply amount B-4. Semiconductor wafer cleaning conditions

B-5. Polishing pad cleaning conditions B-5-1. Normal cleaning conditions B-5-1-1. Brush rotation speed B-5-1-2. Brush swing speed B-5-1-3. Brush swing range B-5-1-4. Brush pressing pressure B-5-1-5. Washing time B-5-2. Important cleaning conditions B-5-2-1. Brush rotation speed B-5-2-2. Brush pressing pressure B-5-2-3. Cleaning time

B-6. Geometric parameters B-6-1. Semiconductor wafer diameter B-6-2. Polishing pad rotation center coordinates B-6-3. Top ring rotation center coordinates B-6-4. Top ring swing center coordinates B-6-5. Top ring swing radius B-7. Priority cleaning area, etc.

C. Adhesion-related information C-1. Polishing pad section C-2. Image recognition standard pattern C-3. Foreign matter adhesion region C-4. When the control computer 130 reads the polishing apparatus control program from the storage device, the polishing by the polishing apparatus is started, for example, according to the procedure of the main polishing routine shown in FIG. That is, first, the control computer 130 reads various conditions from a storage device installed as a part thereof. This storage device includes semiconductor wafer (polishing target) transport conditions, polishing conditions (polishing recipe), dressing conditions, semiconductor wafer cleaning conditions, polishing pad (polishing member) cleaning conditions, geometric parameters, and critical cleaning areas, etc. Are stored as various conditions. In addition to various conditions, this storage device also stores a polishing apparatus control program and adhesion related information. This storage device may be an external storage device separate from the control computer 130, for example. In this case, prior to polishing, the control computer 130 reads various conditions from an external storage device using an input device or the like installed in the control computer 130 and stores it in a storage device installed as a part of the control computer 130.

  Once the various conditions are read from the storage device, the control computer 130 is used for specifying the foreign matter adhesion range in the adhesion area specifying unit 120 by the polishing surface diagnosis of the object to be polished, based on the read various conditions, Create multiple standard patterns for image recognition. The standard pattern to be created is, for example, data such as the radial density distribution and the circumferential density distribution of the scratch analyzed from the trajectory data of the foreign matter, the presence / absence of a scratch at a specific position on the polishing surface, as shown in FIG. . The control computer 130 stores the created standard pattern in the storage device. The method for creating the trajectory data of the foreign matter is as described above.

  Next, the control computer 130 controls the polishing apparatus so that one semiconductor wafer is taken out from the wafer cassette 21 by the transfer robot 24 and transferred to the mounting table 28. Then, after the semiconductor wafer is transferred to the mounting table 28, the control computer 130 controls the transfer robot 81 and the like so as to transfer the semiconductor wafer to the reversing machine 100 provided in the rotary wafer station 98.

  When the semiconductor wafer is transferred to the reversing machine 100, the control computer 130 executes a polishing preparation end determination routine shown in FIG. In this polishing preparation completion determination routine, a dressing flag that is turned ON during dressing, a foreign matter adhesion flag that is turned ON when foreign matter is attached to the polishing pad, and a cleaning flag that is turned ON while cleaning the polishing pad are referred to. While any of the flags is ON, the next processing is waited. When all the flags are OFF, the foreign matter adhesion monitoring end flag by the polishing pad diagnosis is turned ON, and the polishing preparation end determination routine is ended. This state means that the semiconductor wafer is ready for polishing with the polishing pad 10 of the polishing table 54. Further, when the foreign matter adhesion monitoring end flag by the polishing pad diagnosis is turned ON, when the foreign matter on the surface of the polishing pad 10 is monitored by the adhesion region specifying unit 110, the control computer 130 ends the foreign matter monitoring and attaches the adhesion region. The specific unit 110 is saved in the save area.

  Next, the control computer 130 rotates the rotary wafer station 98 and inverts the semiconductor wafer with the reversing machine 100, and then transfers the wafer to the top ring 52 and controls the polishing apparatus so as to be conveyed to the polishing table 54. When the semiconductor wafer is transferred to the polishing table 54, the control computer 130 controls the polishing apparatus to polish the semiconductor wafer under the polishing conditions read from the storage device. Semiconductor wafer polishing conditions are: polishing pad rotation speed, semiconductor wafer (top ring) rotation speed, semiconductor wafer (top ring) swing speed, semiconductor wafer (top ring) swing range, polishing time, polishing pressure, and slurry supply. Such as flow rate.

  When the polishing of the semiconductor wafer is completed, the control computer 130 is divided into two series: a series in which the semiconductor wafer is cleaned and dried and returned to the wafer cassette 21, and a series in which the polishing pad 10 is dressed and cleaned to prepare for the next polishing. Perform processing in parallel.

  First, the series of dressing and cleaning the polishing pad to prepare for the next polishing will be described. This series includes three operations: an operation of dressing the polishing pad, an operation of cleaning the polishing pad, and an operation of monitoring the adhesion of foreign matter on the surface of the polishing pad. When the polishing of the semiconductor wafer is completed, the control computer 130 executes in parallel a dressing routine shown in FIG. 12, a polishing pad cleaning routine shown in FIG. 13, and a foreign matter adhesion monitoring routine shown in FIG.

  First, the dressing routine shown in FIG. 12 will be described. In the dressing routine, the control computer 130 turns on a dressing flag indicating that the polishing pad 10 is being dressed, and controls the polishing apparatus to dress the polishing pad 10 with the dresser 58. The dressing conditions at that time are the conditions read from the storage device at the start of polishing. The dressing conditions include a polishing pad rotation speed, a dresser rotation speed, a dresser swing speed, a dresser swing range, a dressing time, a dressing pressure, and a cleaning liquid supply flow rate. When the dressing of the polishing pad 10 is completed, the control computer 130 turns off the dressing flag. This completes the dressing routine.

  Next, the polishing pad cleaning routine shown in FIG. 13 will be described. In the polishing pad cleaning routine, the control computer 130 first turns on a cleaning flag indicating that the polishing pad 10 is being cleaned. Next, in this example, the control computer 130 determines whether or not the number of polished semiconductor wafers is the 3nth (n = 1, 2, 3,...).

  When the polished semiconductor wafer is not the 3nth wafer, the control computer 130 controls the polishing apparatus so that the entire polishing pad 10 is uniformly cleaned with the brush of the cleaning unit 112. The cleaning conditions at that time are normal cleaning conditions read from the storage device at the start of polishing. The normal cleaning conditions are brush rotation speed, brush swing speed, brush swing range, brush pressing pressure, cleaning time, and the like. The polishing pad rotation speed is the polishing pad rotation speed of a dressing routine executed in parallel.

  When the polished semiconductor wafer is the 3nth wafer, the control computer 130 reads the important cleaning range of the polishing pad 10 from the storage device, and polishes the important cleaning range so that it is cleaned with the brush of the cleaning unit 112. Control the device. The focused cleaning range at that time is the focused cleaning range stored in the storage device prior to polishing and / or the focused cleaning range stored in the storage device in the focused cleaning range calculation routine described later. In the case of this example, the intensive cleaning range is stored as one of the section numbers obtained by dividing the polishing pad 10 into five ring-shaped sections as shown in FIG. The cleaning conditions are the priority cleaning conditions read from the storage device at the start of polishing. The priority cleaning conditions include brush rotation speed, brush pressing pressure, and cleaning time. The polishing pad rotation speed is the polishing pad rotation speed of a dressing routine executed in parallel.

  In the case of the polishing apparatus of this example, a brush whose diameter is larger than the width of the priority cleaning range is used as the brush of the cleaning unit 112. Therefore, if the position of the brush of the cleaning unit 112 is appropriately set based on the priority cleaning range read from the storage device by the control computer 130, the priority cleaning range of the polishing pad 10 is prioritized without the brush being swung. Can be washed. The position of the brush of the cleaning unit 112 is the control computer 130 so that the distance from the rotation center of the polishing table 54 is an intermediate value between the inner radius and the outer radius of the section in the priority cleaning range as the brush center coordinates. Set by Further, the position of the brush of the cleaning unit 112 may be stored in advance in the storage device, for example, as a position where each of the five sections shown in FIG. When the cleaning of the polishing pad 10 is completed, the control computer 130 turns off the cleaning flag. This is the end of the polishing pad cleaning routine.

  Next, a foreign matter adhesion monitoring routine based on the polishing pad diagnosis shown in FIG. 14 will be described. In the foreign matter adhesion monitoring routine based on the polishing pad diagnosis, the control computer 130 first turns off the foreign matter adhesion monitoring end flag based on the polishing pad diagnosis. Next, the control computer 130 moves the adhesion area specifying unit 110 to the monitoring area of the polishing pad 10. The adhesion region specifying unit 110 monitors the adhesion of foreign matter on the polishing pad 10.

  While the foreign matter adhesion monitoring end flag by the polishing pad diagnosis is OFF, the control computer 130 monitors a signal from the adhesion region specifying unit 110. When foreign matter adheres to the surface of the polishing pad 10, a peak P as shown in FIG. 3C appears in the signal from the adhesion region specifying unit 110. The control computer 130 analyzes the signal from the adhesion region specifying unit 110 and detects this peak P to determine the adhesion of foreign matter on the polishing pad 10. However, the control computer 130 does not determine that the foreign matter has adhered only by detecting the peak P once. This is because there is a possibility that foreign matter moving along with the cleaning liquid on the surface of the polishing pad 10 has been detected. Therefore, in this example, when the displacement sensor 224 that has detected the peak P detects the peak P again even after the polishing pad 10 has made one revolution, it is determined that foreign matter has adhered to the polishing pad 10.

  When it is determined that foreign matter has adhered to the polishing pad 10, the control computer 130 turns on the foreign matter adhesion flag. The foreign matter adhesion flag indicates that while foreign matter is attached to the polishing pad 10, that is, while the signal of the displacement sensor 224 that has detected the peak P continues to transmit the peak P in accordance with the rotation period of the polishing pad. It is ON.

  After the foreign matter adhesion flag is turned ON, the control computer 130 specifies the foreign matter adhesion range. In this example, the section (see FIG. 9A) that is handled by the displacement sensor 224 that has detected the peak P is the foreign matter adhesion range. After that, the control computer 130 controls the polishing apparatus so that the specified foreign matter adhesion range is mainly cleaned by the cleaning unit 112. At that time, the polishing pad cleaning routine executed in parallel is interrupted. The cleaning conditions in this case are the priority cleaning conditions read from the storage device at the start of polishing. The priority cleaning conditions include brush rotation speed, brush pressing pressure, and cleaning time. The polishing pad rotation speed is the polishing pad rotation speed of a dressing routine executed in parallel.

  In the case of the polishing apparatus of this example, the diameter of the brush of the cleaning unit 112 is larger than the width of the foreign matter adhesion range. Therefore, if the position of the brush is appropriately set based on the specified foreign matter adhesion range, the foreign matter adhesion range can be intensively cleaned without swinging the brush. The position of the brush is determined by the control computer 130 so that the distance from the rotation center of the polishing table 54 is an intermediate value between the inner radius and the outer radius of the ring-shaped section in the foreign matter adhesion range as the coordinates of the brush center. Is set. Further, the position of the brush may be stored in advance in the storage device as a position where each of the five sections shown in FIG. Here, in the case of the polishing apparatus of this example, the dividing method of the section of the above-mentioned important cleaning range and the section of the foreign substance adhesion range is the same, so the brush positions stored in the storage device in advance may be common.

  After the specified foreign matter adhesion range is cleaned with the brush of the cleaning unit 112 for the cleaning time set in the priority cleaning condition, the control computer 130 determines again whether foreign matter has adhered, and foreign matter has adhered to the polishing pad 10. If so, the above process is repeated. If no foreign matter has adhered to the polishing pad 10, the foreign matter adhesion flag is turned OFF and the polishing pad cleaning routine is restarted. At this time, if the cleaning end time scheduled in the polishing pad cleaning routine has passed, the end processing of the polishing pad cleaning routine is immediately executed.

  When the foreign matter adhesion monitoring end flag by the polishing pad diagnosis is turned ON, the control computer 130 moves the adhesion region specifying unit 110 to the retreat area, and ends the foreign matter adhesion monitoring routine by the polishing pad diagnosis.

  While the foreign matter adhesion flag is ON, as shown in FIG. 11, the foreign matter adhesion monitoring end flag based on the polishing pad diagnosis does not become ON, so the foreign matter adhesion monitoring routine based on the polishing pad diagnosis does not end. Further, polishing of the next semiconductor wafer is not started. Therefore, if the foreign matter on the polishing pad 10 cannot be removed even after extensively cleaning the foreign matter adhesion range, an alarm may be issued to stop the polishing apparatus. Thereby, the maintenance staff of the polishing apparatus can take measures such as replacing the polishing pad.

  In parallel with the cleaning of the specified foreign matter adhesion range, the control computer 130 calculates the priority cleaning range. In the priority cleaning range calculation routine, as shown in FIG. 16, the control computer 130 stores the specified adhesion range in the storage device, and reads the accumulated adhesion range from the storage device. Next, the priority cleaning range is calculated. In this example, the accumulated adhesion range is counted, and the section with the largest number of adhesions is set as the priority cleaning range. Finally, the calculated important cleaning range is stored in the storage device. Here, instead of calculating the intensive cleaning range from the accumulated adhesion range, the number of adhesions for each section is counted in advance and recorded in the storage area, and when the foreign substance adhesion range is specified, the count of the corresponding section is set to 1. When added, the section with the largest count becomes the priority cleaning range. In this way, the processing time can be shortened.

  Note that if a foreign matter that has not been removed from the polishing pad 10 is detected again even after intensive cleaning, the intensive cleaning range calculation routine is not executed to prevent double counting. Whether or not the detected foreign matter is the same foreign matter is determined by whether or not the peak P of the signal from the displacement sensor 224 appears periodically in synchronization with the rotation of the polishing pad.

  Next, returning to the polishing main routine shown in FIG. 10, a series of cleaning and drying the semiconductor wafer and returning it to the wafer cassette 21 will be described. When the polishing of the semiconductor wafer is completed, the control computer 130 controls the transfer robot 81 and the like to transfer the semiconductor wafer from the polishing table 54 to the cleaning machine 83. Next, the control computer 130 controls the polishing apparatus so that the semiconductor wafer is cleaned by the cleaning machine 83 and then transferred to the cleaning machine 26 by the transfer robot 81. In the cleaning machine 26, the semiconductor wafer is cleaned and dried.

  When the cleaning and drying of the semiconductor wafer in the cleaning machine 26 is completed, the control computer 130 transfers the semiconductor wafer from the cleaning machine 26 to the mounting table 28 by the transfer robot 81, and then specifies the adhesion region by the polishing surface diagnosis by the transfer robot 24. The polishing apparatus is controlled to transfer the semiconductor wafer to the unit 120.

  When the semiconductor wafer is transferred to the adhesion region specifying unit 120, the control computer 130 executes a foreign matter adhesion determination routine based on a polishing surface diagnosis of the semiconductor wafer (polishing target), and adheres foreign matter on the surface of the polishing pad (polishing member). Judgment and identification of foreign matter adhesion range are performed. In the foreign matter adhesion determination routine based on the polished surface diagnosis, the control computer 130 executes the procedure shown in FIG.

  The control computer 130 first captures the image of the polished surface of the semiconductor wafer with the adhesion region specifying unit 120 and captures the image data. Next, corrections such as noise removal, sharpening, and binarization are performed on the captured image data, and line extraction is performed from the corrected image data. Next, the control computer 130 performs pattern recognition to determine whether the extracted line is a scratch. In pattern recognition, it is determined whether or not it is a scratch from the length or shape of the extracted line. When it is determined that there is no scratch on the polished surface, the control computer 130 ends the foreign matter adhesion determination routine based on the polished surface diagnosis.

  If it is determined that there is a scratch on the polished surface, the control computer 130 analyzes the image data obtained by extracting only the line determined to be a scratch, and determines the radial density distribution, circumferential density distribution of the scratch, and a specific position on the polished surface. The presence / absence of scratches is used as a detection pattern. Next, the control computer 130 determines a standard pattern closest to the detection pattern by the nearest neighbor method. Then, the control computer 130 specifies the foreign matter adhesion range (distance from the center of the polishing pad) of the standard pattern as the foreign matter adhesion range on the surface of the polishing pad (polishing member).

  Next, the control computer 130 determines which of the five sections shown in FIG. 9A corresponds to the specified foreign matter adhesion range. When the determined section is the same as the foreign matter adhesion range specified by the polishing pad diagnosis, the control computer 130 ends the foreign matter adhesion determination routine by the polishing surface diagnosis. If the determined section is not the foreign matter attachment position specified by the polishing pad diagnosis, or if no foreign matter attachment is detected by the polishing pad diagnosis, the control computer 130 turns on the foreign matter attachment flag and sets the specified foreign matter attachment range. The polishing apparatus is controlled so that the cleaning unit 112 performs intensive cleaning. The cleaning conditions at this time are the priority cleaning conditions read from the storage device at the start of polishing. The priority cleaning conditions include brush rotation speed, brush pressing pressure, and cleaning time. The polishing pad rotation speed is the polishing pad rotation speed of the dressing routine.

  If the polishing pad cleaning routine is executed at this time, the polishing pad cleaning routine is interrupted. Further, when the intensive cleaning of the foreign matter adhesion range is executed in the foreign matter adhesion monitoring routine by the polishing pad diagnosis, the process waits until the intensive cleaning in the foreign matter adhesion monitoring routine by the polishing pad diagnosis is completed.

  In this example, the diameter of the brush of the cleaning unit 112 is sufficiently larger than the interval of the foreign matter adhesion range of the standard pattern. Therefore, if the position of the brush is appropriately set based on the specified foreign matter adhesion range, the foreign matter adhesion range can be intensively cleaned without swinging the brush. The position of the brush is set by the control computer 130 so that the distance from the center of rotation of the polishing table 54 becomes the standard pattern foreign matter adhesion range as the coordinates of the brush center.

  After performing the cleaning by the cleaning unit 112 for the cleaning time when the specified foreign matter adhesion range is read under the priority cleaning conditions, the control computer 130 turns off the foreign matter adhesion flag and ends the foreign matter adhesion determination routine based on the polishing surface diagnosis. If the polishing pad cleaning routine is interrupted, the polishing pad cleaning routine is restarted. At this time, if the cleaning end time scheduled in the polishing pad cleaning routine has passed, the end processing of the polishing pad cleaning routine is immediately executed.

  In parallel with the cleaning of the foreign matter adhesion range by the cleaning unit 112, the control computer 130 executes a priority cleaning range calculation routine. The contents of the priority cleaning range calculation routine are as described above. In the priority cleaning range calculation, the section determined from the foreign matter adhesion range is the foreign matter adhesion range. Apart from this, the foreign matter adhesion range specified by pattern recognition may be stored and accumulated.

  Returning to the polishing main routine of FIG. 10, when the foreign matter adhesion determination by the polishing surface diagnosis is completed, the control computer 130 takes out the semiconductor wafer from the foreign matter adhesion range specifying unit 120 and conveys it to the wafer cassette 21. To control. In the foreign matter adhesion determination routine based on the polishing diagnosis, even if there is a scratch and the adhesion range is different from the polishing pad diagnosis, and the foreign matter adhesion range is mainly cleaned, if the foreign matter adhesion flag is turned ON, The control computer 130 can control the transfer robot 24 and the like so that the semiconductor wafer is taken out from the foreign matter adhesion range specifying unit 120 and transferred to the wafer cassette 21. Then, the control computer 130 determines whether or not a predetermined number of processes have been completed. If the process is completed, the control computer 130 ends all the processes, and if not completed, the polishing apparatus starts the process of the next semiconductor wafer. To control.

  The above has been mainly described with reference to FIGS. 6 and 10 to 16. However, the above description is merely an example of the present invention, and the scope of the present invention is not limited to the above-described content. Needless to say.

  Up to now, an example of a chemical mechanical polishing apparatus provided with an adhesion region specifying unit 226 for diagnosing a polishing pad (abrasive member) using a displacement sensor 224 using a displacement sensor as shown in FIG. As shown in FIG. 4, the adhesion region specifying units 110 and 111 shown in FIG. 2 include the adhesion region specifying unit 206 that diagnoses the polishing member in a contact manner using the pressure sensor 204, and the imaging device 230 shown in FIG. You may make it provide the adhesion area | region specific | specification part 234 which diagnoses a polishing member by a non-contact system.

  Further, the adhesion region specifying portions 110 and 111 that directly detect foreign matter on the polishing member (polishing pad) and the polished surface (polishing surface) of the object to be polished (semiconductor wafer) are diagnosed, and the polishing member ( Although an example of a chemical mechanical polishing apparatus provided with both of the adhesion region specifying unit 120 that indirectly detects foreign matter on the polishing pad) is shown, the chemical mechanical polishing apparatus provided with either one of the adhesion region specifying units is May be. In addition, although an example of a chemical mechanical polishing apparatus provided with an adhesion region specifying unit has been shown, the polishing member is not provided with an adhesion region specifying unit, and reads information from a storage medium storing information on an important cleaning position or an important cleaning region. It may be a chemical mechanical polishing apparatus provided with a control unit that controls the cleaning unit so as to focus cleaning on the surface important cleaning position or the important cleaning range. In this case, adhesion of foreign matters can be prevented by intensively cleaning the priority cleaning position or the priority cleaning range.

  In addition, although an example of a chemical mechanical polishing apparatus in which all the processes are controlled by one control computer 130 is shown, the adhesion region specifying unit may include an independent control unit. In this case, the control unit for controlling the entire chemical mechanical polishing apparatus and the control unit for controlling the adhesion region specifying unit are configured to communicate with each other so that each control unit can perform the polishing process in cooperation with each other. It has become. In this case, the specified foreign substance adhesion range may be stored in a storage device provided in the adhesion area specifying unit.

FIG. 17 is a system configuration diagram of the adhesion region specifying device when the adhesion region specifying unit 120 in the above example is an adhesion region specifying device independent of the polishing apparatus. This attached area specifying device has a central processing unit (arithmetic unit) 140, a main memory 142, a storage unit 144, an input unit (reading unit) 146, and an output unit 148, and each is configured to function in cooperation. ing.
For example, the following information is stored in the storage device 144.

A. Adhesion area identification device control program A-1. Various condition reading routine A-2. Standard pattern creation routine A-3. Image reading routine A-4. Image analysis routine A-5 Foreign matter adhesion range display routine, etc.

B. Various conditions B-1. Polishing conditions (polishing recipe)
B-1-1. Polishing pad rotation speed B-1-2. Semiconductor wafer (top ring) rotation speed B-1-3. Semiconductor wafer (top ring) swing speed B-1-4. Semiconductor wafer (top ring) rocking range B-1-5. Polishing time B-2. Geometric parameters B-2-1. Semiconductor wafer diameter B-2-2. Polishing pad rotation center coordinates B-2-3. Top ring rotation center coordinates B-2-4. Top ring swing center coordinates B-2-5. Top ring swing radius, etc.

C. Adhesion-related information C-1. Image recognition standard pattern C-2. Polished surface image, etc.

  FIG. 18 shows a method for identifying a foreign matter adhesion range on the surface of a polishing member such as a polishing pad that causes a scratch from the polishing surface of an object to be polished such as a scratched semiconductor wafer by using this adhesion region specifying device. This will be described below with reference to the foreign matter adhesion range specifying process flow shown in FIG.

  First, when a process start command is input from an input device such as a keyboard, mouse, or touch panel, the central processing unit (arithmetic unit) 140 receives various control conditions from the storage device 144 in response to a control program command in the main memory 142. Is read. As described above, the storage device 144 stores polishing conditions (polishing recipes), geometric parameters, and the like as various conditions.

  Here, when the polishing object is a semiconductor wafer and the polishing apparatus is a polishing apparatus having a polishing table with a polishing pad and a top ring as shown in FIG. 7, the polishing conditions (polishing recipe) are polishing. These are a pad rotation speed, a semiconductor wafer (top ring) rotation speed, a semiconductor wafer (top ring) swing speed, a semiconductor wafer (top ring) swing range, and a polishing time. Similarly, the geometric parameters are semiconductor wafer diameter, polishing pad rotation center coordinates, top ring rotation center coordinates, top ring rocking center coordinates, top ring rocking radius, and the like.

  These various conditions are read from a polishing device, an external storage device, or the like using an input device (reading device) 146 installed in the attachment region specifying device prior to the foreign matter attachment range specifying processing, or a keyboard, Manual input from an input device such as a mouse or touch panel. In addition to various conditions, the storage device 144 also stores an adhesion position specifying device control program and adhesion related information.

  When the various conditions are read from the storage device 144, the central processing unit 140 receives a command from the control program in the main memory 142, and uses the plurality of conditions based on the read various conditions to be used for specifying the foreign matter adhesion range. A standard pattern for image recognition is created and stored in the storage device 144 as adhesion related information. The standard pattern to be created is, for example, foreign object locus data as shown in FIG. The method for creating the trajectory data of the foreign matter is as described above.

  Next, the central processing unit 140 receives an instruction of a control program in the main memory 142 and reads an image obtained by photographing a polished surface having a scratch. At this time, the central processing unit 140 may read an image obtained by photographing the polished surface from the photographing device using the input device (reading device) 146, or may use a flexible disk or the like using the input device (reading device) 146. You may read from external storage media, such as CD-ROM. In addition, the central processing unit 140 may read an image obtained by photographing the polished surface that is stored in advance in the storage device of the adhesion area specifying device.

  Next, the central processing unit 140 receives an instruction of a control program in the main memory 142, performs correction (image conversion) such as noise removal, sharpening, and binarization on the read image data, and the corrected image data Line extraction (feature extraction) is performed. Next, the central processing unit 140 receives a command from the control program in the main memory 142, executes pattern recognition (image recognition), and further extracts scratches from the extracted lines.

  Next, the central processing unit 140 receives an instruction from the control program in the main memory 142, determines the standard pattern closest to the detection pattern by image recognition using the image data from which the scratch is extracted as a detection pattern, and The foreign matter adhesion range (distance of foreign matter from the center of the polishing pad) is specified as the foreign matter adhesion range on the polishing member surface.

  Here, the image recognition includes pattern recognition such as Nearest Neighbor Method, Bayes identification rule, dynamic programming matching (DP matching), Hidden Markov Model. In this example, performing at least one of image conversion, feature extraction, and image recognition is called image analysis. Next, the central processing unit 140 receives a command from the control program in the main memory 142 and outputs a foreign matter adhesion range to an output device 148 such as a printer or a display.

  As described above, when the adhesion region specifying device of this example is used, a polishing member such as a polishing pad is used when a semiconductor wafer or the like is polished by a polishing apparatus that does not have an adhesion region specifying portion and a scratch occurs on the polishing surface. It is possible to specify the foreign matter adhesion position or the foreign matter adhesion range on the surface.

  In the above description, an example in which a standard pattern is created in the foreign matter adhesion range identification processing flow is shown. However, a standard pattern created in advance is stored in the storage device 144 of the adhesion region identification device or an external storage medium. Of course, it is possible not to create a standard pattern by reading in the foreign matter adhesion range specifying process flow. In addition, the standard pattern created in the foreign matter attachment range identification processing flow is stored in the external storage device, not the storage device 144 of the adhesion region identification device, and is read from the external storage and used in the foreign matter attachment range identification processing flow. You may do it.

  In addition, the foreign matter adhesion range specifying process using the foreign matter trajectory data has been described, but the radial density distribution and the circumferential density distribution of the scratch analyzed from the trajectory data instead of the trajectory data, and the scratch at a specific position on the polishing surface The foreign matter adhesion range specifying process may be performed using data such as presence / absence of the foreign matter. In this case, the image data obtained by extracting the scratch is analyzed, and the detection pattern includes the radial density distribution and the circumferential density distribution of the scratch, the presence / absence of the scratch at a specific position on the polishing surface, and the like. Corresponding to this, the standard pattern may be the radial density distribution of the scratch, the circumferential density distribution, and the presence / absence of a scratch at a specific position on the polishing surface.

It is a figure attached | subjected to description of the foreign material adhesion position and foreign material adhesion range on the surface of an abrasive member. It is a figure which shows the adhesion area | region specific | specification part which specifies the foreign material adhesion position or foreign material adhesion range on the surface of a grinding | polishing member using a pressure sensor. It is a figure which shows the adhesion area | region specific | specification part which specifies the foreign material adhesion position or foreign material adhesion range on the surface of a grinding | polishing member using a displacement sensor. It is a figure which shows the adhesion area | region specific | specification part which specifies the foreign material adhesion position or foreign material adhesion range on the surface of a grinding | polishing member by a non-contact system. It is a figure which shows the adhesion area | region specific | specification part which diagnoses the surface after grinding | polishing of a grinding | polishing target object by a non-contact method, and identifies the foreign material adhesion position or foreign material adhesion range on the surface of a grinding | polishing member. It is a top view which shows the arrangement structure of each part of the chemical mechanical polishing apparatus of embodiment of this invention. It is a schematic sectional drawing which shows a part of top ring and a polishing table. It is a figure which shows the example of the scratch pattern used as a standard pattern. It is a figure attached | subjected to description of the method of calculating the probability that the foreign material adhered from the accumulation | storage data of the specific range which the adhesion area | region identification part specified. It is a control flowchart of a polishing main routine. It is a control flowchart of a polishing preparation end determination routine. It is a control flow figure of a dressing routine. It is a control flowchart of a polishing pad cleaning routine. It is a control flow figure of a foreign substance adhesion monitoring routine by polishing pad diagnosis. It is a control flow figure of a foreign substance adhesion judging routine by polishing surface diagnosis. It is a control flowchart of a priority cleaning range calculation routine. It is a system configuration | structure figure of an adhesion area | region identification apparatus. FIG. 18 is a processing flowchart for specifying a foreign substance adhesion range in the adhesion area identification device shown in FIG. 17.

Explanation of symbols

2 Semiconductor wafer (object to be polished)
5,6 Airbag 10 Polishing pad (polishing member)
14 Retainer ring 52, 53 Top ring 54, 55, 56, 57 Polishing table 58, 59, 68, 69 Dresser 60, 61 Abrasive liquid nozzle 70 Wafer station 893, 94 Sensor 95, 96 Rinse nozzle 98 Rotary wafer station 108 Pressure Adjustment mechanism 110, 111 Adhering area specifying unit 112, 113 Cleaning unit 120 Adhering area specifying unit 130 Control computer 140 Central processing unit 142 Main memory 144 Storage device 146 Input device (reading device)
148 Output devices 200 and 202 Polishing member 204 Pressure sensor 206 Adhering region specifying unit 208 Polishing head 210 Polishing object 212 Computer 224 Displacement sensor 226 Adhering region specifying unit 230 Imaging device 232 Computing device 234 Adhering region specifying unit 250 Imaging device 252 Computing device 254 Adhesion area identification part

Claims (41)

A polishing method for polishing the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object,
Identify the foreign material adhesion position or foreign material adhesion range on the surface of the abrasive member,
A polishing method characterized by intensively cleaning a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member. A polishing method for polishing the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object,
Read information about the critical cleaning position or critical cleaning range of the polishing member surface from the storage medium to the computer,
A polishing method characterized by intensively cleaning an important cleaning position or an important cleaning range on the surface of the polishing member. A polishing method for polishing the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object,
Read information about the critical cleaning position or critical cleaning range of the polishing member surface from the storage medium to the computer,
Identify the foreign material adhesion position or foreign material adhesion range on the surface of the abrasive member,
A polishing method characterized by intensively cleaning at least one of a focused cleaning position or a focused cleaning range on the surface of the polishing member and a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member. A polishing method for polishing the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object,
Identify the foreign material adhesion position or foreign material adhesion range on the surface of the abrasive member,
Store and store the foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member,
Calculate the critical cleaning position or critical cleaning range from the accumulated foreign matter adhesion position or foreign matter adhesion range on the accumulated polishing member surface,
A polishing method characterized by intensively cleaning at least one of the calculated important cleaning position or important cleaning range on the surface of the polishing member and the specified foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member.   5. The polishing method according to claim 1, wherein the detection unit detects that foreign matter has adhered to the surface of the polishing member, and specifies the foreign matter attachment position or foreign matter attachment range on the surface of the polishing member.   The polishing method according to claim 5, wherein image analysis of the surface of the polishing member is performed to detect that foreign matter has adhered to the surface.   The polishing method according to claim 1, 3 or 4, wherein a polishing surface of the polishing object after polishing is diagnosed to identify a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member.   8. The polishing method according to claim 7, wherein the polishing surface is diagnosed by analyzing the image of the polished surface of the object to be polished.   Diagnose the surface of the polishing member, specify the position or range of foreign matter adhesion on the surface of the polishing member as the position or range to be cleaned intensively, and the specified position or range to be cleaned intensively. A method for identifying a cleaning region on a surface of an abrasive member, characterized by storing and accumulating. While applying pressure between the polishing member and the polishing object, the polishing member and the polishing object are moved relative to each other to polish the polishing object,
A method for identifying a cleaning region on a surface of a polishing member, wherein the polishing surface of the polishing object is diagnosed to identify a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member to be intensively cleaned.   11. The method for identifying a cleaning region on a polishing member surface according to claim 10, wherein information specified as a foreign matter adhesion position or a foreign matter adhesion range on the polishing member surface is stored and accumulated.   The method for identifying a cleaning region of a polishing member surface according to claim 10, wherein the polishing surface is diagnosed by performing image analysis on the polishing surface of the object to be polished.   An adhesion area specifying method characterized in that an image obtained by photographing a polished surface of an object to be polished is subjected to image analysis to determine a foreign substance adhesion position or a foreign substance adhesion range on the surface of the polishing member. A polishing apparatus that polishes the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object,
An adhesion region specifying part for specifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member;
A polishing apparatus, comprising: a cleaning unit that intensively cleans a foreign material adhesion position or a foreign material adhesion range on the surface of the polishing member specified by the adhesion region specifying unit. A polishing apparatus that polishes the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object,
A cleaning section for cleaning the surface of the polishing member;
Control for reading the information from the storage medium storing the information on the important cleaning position or the important cleaning range on the surface of the polishing member and controlling the cleaning unit so as to focus on the important cleaning position or the important cleaning range on the surface of the polishing member A polishing apparatus comprising a portion. A polishing apparatus that polishes the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object,
A cleaning section for cleaning the surface of the polishing member;
An adhesion region specifying part for specifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member;
Information is read from a storage medium that stores information on the important cleaning position or important cleaning range of the polishing member surface, and is specified by the read important cleaning position or important cleaning range of the polishing member surface and the adhesion region specifying unit A polishing apparatus comprising: a control unit that controls the cleaning unit so that at least one of a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member is preferentially washed. A polishing apparatus that polishes the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object,
A cleaning section for cleaning the surface of the polishing member;
An adhesion region specifying part for specifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member;
Stores and accumulates the foreign matter adhesion position or foreign matter adhesion range on the surface of the polishing member specified by the adhesion region specifying unit, and performs the priority cleaning position or the critical cleaning from the accumulated foreign matter adhesion position or foreign matter adhesion range on the polishing member surface. And calculating at least one of the calculated important cleaning position or important cleaning range of the polishing member surface and the foreign matter adhesion position or foreign matter adhesion range specified by the adhesion region specifying unit. A polishing apparatus comprising: a control unit that controls the cleaning unit so as to perform cleaning.   The adhesion region specifying unit has a detection unit that detects foreign matter attached to the surface of the polishing member, and specifies a foreign matter attachment position or a foreign matter attachment range on the surface of the polishing member. 17. The polishing apparatus according to 17.   19. The polishing apparatus according to claim 18, wherein the adhesion region specifying unit includes an image analysis device that performs image analysis on the surface of the polishing member and detects foreign matter attached to the surface.   The adhesion region specifying unit includes a diagnosis device that diagnoses a polished surface of a polishing object after polishing and specifies a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member. 17. The polishing apparatus according to 17.   21. The polishing apparatus according to claim 20, wherein the diagnostic apparatus is an image analysis apparatus that performs image analysis on a polished surface after polishing of an object to be polished to diagnose the polished surface.   The polishing apparatus according to claim 16, wherein the control unit stores and accumulates information specified by the attachment region specifying unit as a foreign matter attachment position or a foreign matter attachment range on the surface of the polishing member. A device for specifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of an abrasive member,
A reading device for reading a standard pattern from a storage medium;
A reading device that reads an image of the polished surface of the object to be polished;
An arithmetic unit that identifies a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member by performing image analysis using the read standard pattern and image;
An output device for outputting the foreign matter adhesion position or foreign matter adhesion range identified by the arithmetic device;
A device for identifying an adhesion region characterized by comprising: A device for specifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of an abrasive member,
A reading device for reading the geometric parameters of the polishing device and the polishing conditions of the object to be polished;
A standard pattern creating device that creates a standard pattern using the read geometric parameters and polishing conditions;
A reading device that reads an image of the polished surface of the object to be polished;
An arithmetic device that identifies a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member by performing image analysis using the created standard pattern and the read image;
An output device for outputting the foreign matter adhesion position or foreign matter adhesion range identified by the arithmetic device;
A device for identifying an adhesion region characterized by comprising: In order to remove foreign matter adhering to the surface of the polishing member by cleaning,
Adhesion area identification procedure for identifying the foreign substance adhesion position or foreign substance adhesion range on the surface of the polishing member,
The important cleaning condition reading procedure for reading the cleaning conditions when the abrasive member surface is intensively read from the storage medium, and the foreign matter adhesion position or foreign matter adhesion range on the specified abrasive member surface with the read important cleaning conditions Priority washing procedure to wash,
A program for running To prevent foreign matter from adhering to the surface of the abrasive member,
Importance cleaning area reading procedure for reading information on the important cleaning position or important cleaning range of the polishing member surface from the storage medium,
The important cleaning condition reading procedure for reading the cleaning conditions when the abrasive member surface is intensively read from the storage medium, and the important cleaning position or the important cleaning range of the read abrasive member surface with the read important cleaning conditions Priority washing procedure to wash,
A program for running In order to prevent foreign matter from adhering to the surface of the abrasive member, or to remove the foreign matter adhering to the surface of the abrasive member by washing,
Importance cleaning area reading procedure for reading information on the important cleaning position or important cleaning range of the polishing member surface from the storage medium,
Adhesion area identification procedure for identifying the foreign substance adhesion position or foreign substance adhesion range on the surface of the polishing member,
The important cleaning condition reading procedure for reading the cleaning conditions when the abrasive member surface is mainly cleaned from the storage medium, the important cleaning position or the important cleaning range of the read abrasive member surface, and the specified abrasive member surface A intensive cleaning procedure for cleaning at least one of the foreign matter adhesion position or the foreign matter adhesion range under the read intensive cleaning conditions;
A program for running In order to prevent foreign matter from adhering to the surface of the abrasive member, or to remove the foreign matter adhering to the surface of the abrasive member by washing,
Adhesion area identification procedure for identifying the foreign substance adhesion position or foreign substance adhesion range on the surface of the polishing member,
An adhesion region storage procedure for storing and accumulating foreign matter adhesion positions or foreign matter adhesion ranges on the surface of the polishing member;
A priority cleaning region calculation procedure for calculating a priority cleaning position or a critical cleaning range from the accumulated foreign matter adhesion position or foreign matter adhesion range on the surface of the abrasive member;
The important cleaning condition reading procedure for reading the cleaning conditions when the polishing member surface is mainly cleaned from the storage medium, the calculated important cleaning position or the important cleaning range of the polishing member surface, and the specified polishing member surface A intensive cleaning procedure for cleaning at least one of the foreign matter adhesion position or the foreign matter adhesion range under the read intensive cleaning conditions;
A program for running   The adhesion area specifying procedure is an adhesion area specifying procedure for detecting a foreign substance adhesion position or a foreign substance adhesion range on the surface of the polishing member by detecting that a foreign substance has adhered to the surface of the polishing member. The program according to claim 25, 27 or 28.   30. The program according to claim 29, wherein the adhesion region specifying procedure includes a procedure of performing image analysis on the surface of the polishing member and detecting that a foreign substance has adhered to the surface.   26. The adhesion area specifying procedure is an adhesion area specifying procedure for diagnosing a polished surface of a polishing object after polishing and specifying a foreign substance adhesion position or a foreign substance adhesion range on the surface of the polishing member. , 27 or 28.   32. The program according to claim 31, wherein the adhesion region specifying procedure includes a procedure of diagnosing the polished surface by image analysis of the polished surface after polishing of the polishing object. In order to store and store the foreign substance attachment position or foreign substance attachment range,
A procedure for diagnosing the surface of the polishing member and specifying the position or range of foreign matter adhesion on the surface of the polishing member as a position or range to be intensively cleaned, and the specified position or range to be intensively cleaned Procedures to store and accumulate,
A program for running In order to identify the foreign material adhesion position or the foreign material adhesion range on the surface of the polishing member,
A procedure of polishing the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object, and diagnosing the polishing surface of the polishing object An adhesion area specifying procedure for specifying a foreign substance adhesion position or a foreign substance adhesion range on the surface of the polishing member to be cleaned intensively;
A program for running   In order to store and store the specified foreign substance adhesion position or foreign substance adhesion range, the computer may further execute a procedure for storing and storing information specified as the foreign substance adhesion position or foreign substance adhesion range on the surface of the polishing member. 35. A program according to claim 34, characterized in that:   35. The program according to claim 34, wherein the adhesion region specifying procedure includes a procedure of diagnosing the polished surface by image analysis of the polished surface of the polishing object. In order to identify the foreign material adhesion position or the foreign material adhesion range on the surface of the polishing member,
An adhesion region identification procedure for identifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of the polishing member by image analysis of an image obtained by photographing the polished surface of the object to be polished;
A program for running   37. A computer-readable storage medium on which the program according to claim 25 is recorded. A polishing apparatus that polishes the polishing object by relatively moving the polishing member and the polishing object while applying pressure between the polishing member and the polishing object,
A polishing apparatus comprising: a computer capable of reading a program from the storage medium according to claim 38 and executing the program.   A computer-readable storage medium storing the program according to claim 37. A device for specifying a foreign matter adhesion position or a foreign matter adhesion range on the surface of an abrasive member,
41. An adhesion area specifying apparatus comprising a computer that can read a program from the recording medium according to claim 40 and execute the program.

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