JP2006261501A - Wafer id reader and wafer id reading method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wafer ID reader for reading identification information written on an edge of a semiconductor wafer, wherein the identification information of a plurality of semiconductor wafers can be read in a short time. <P>SOLUTION: The wafer ID reader comprises a wafer holder 33 for holding and rotating the semiconductor wafer fetched from a housing body which can house the plurality of semiconductor wafers; an image obtaining means 57 for taking an image of the edge of the semiconductor wafer held to the wafer holder 33; a position detection sensor 61 for detecting a positioning notch formed at the edge of the semiconductor wafer; and a control means which calculates a distance from a center position of the positioning notch detected by the position detection sensor 61 to a written position of the identification information imaged by the image obtaining means 57, and controls to rotate the wafer holding part 33 so that the identification information is positioned at an image position of the image obtaining means 57 based on this distance. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a wafer ID reading device and a wafer ID reading method for identifying a semiconductor wafer.

In the semiconductor manufacturing process, identification information (hereinafter also referred to as a wafer ID) for specifying a semiconductor wafer is written on the front or back surface of the semiconductor wafer. This wafer ID is used to identify the contents and necessity of various processes for each semiconductor wafer in various processes of the semiconductor manufacturing process and inspection process. By the way, the wafer ID is read by a wafer ID reading apparatus according to the notation position according to the type of semiconductor wafer, the optical conditions for reading the wafer ID, and the reading method according to the notation type of the wafer ID such as characters, symbols and patterns. The reading conditions for reading the wafer ID are different.
For this reason, in the conventional wafer ID reader, in order to read the wafer ID formed in the outer peripheral area of the surface of the semiconductor wafer, the semiconductor wafer is rotated 360 ° and the entire edge of the semiconductor wafer is imaged by the imaging device. The position of the wafer ID is obtained from the obtained image. Then, the imaging apparatus is moved to the wafer ID position to acquire an image including the wafer ID (see, for example, Patent Document 1).
International Publication No. 03/28089

However, in the conventional wafer ID reader, since it is necessary to image the entire surface area of the semiconductor wafer on which the wafer ID can be written, it is necessary to detect the written position of the wafer ID by rotating each semiconductor wafer once by a rotary stage. There is. In addition, it is necessary to adjust the wafer ID reading condition for each semiconductor wafer, and there is a problem that the time for reading the wafer ID becomes long.
The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a wafer ID reading apparatus and a wafer ID reading method capable of reading identification information of a plurality of semiconductor wafers in a short time.

In order to achieve the above object, the present invention provides the following means.
The present invention is a wafer ID reader for reading identification information written on an edge portion of the semiconductor wafer taken out from a storage body containing a plurality of semiconductor wafers, and holding the semiconductor wafer taken out from the storage body And rotating the wafer holding unit, image acquisition means for imaging the edge portion of the semiconductor wafer held by the wafer holding unit, and position detection for detecting the positioning notch formed on the edge portion of the semiconductor wafer A distance from a sensor and a center position of the positioning cutout detected by the position detection sensor to a notation position of the identification information imaged by the image acquisition unit is obtained, and the identification information is calculated based on the distance. Control means for controlling the rotation of the wafer holder so as to be positioned at the imaging position of the image acquisition means. Providing a wafer ID reader for.

  According to another aspect of the present invention, there is provided a process of taking out a plurality of semiconductor wafers from a storage body and transporting the semiconductor wafers to a wafer holder, rotating the semiconductor wafer held by the wafer holders, and rotating the semiconductor wafers by the image acquisition means Imaging the identification information written on the part, rotating the semiconductor wafer held on the wafer holding part, and detecting a positioning notch formed on the edge part of the semiconductor wafer by a positioning sensor; Obtaining a distance from a center position of the positioning notch detected by the position detection sensor to a notation position of the identification information imaged by the image acquisition means, and storing the distance data in a storage means; Each time each semiconductor wafer taken out from the storage body is placed at the reference position, the distance data is stored from the storage means. It reads the data, to provide a wafer ID reading method characterized by comprising the step of positioning the identification information rotation control to the wafer holding portion on the imaging position of the image acquisition means based on the distance data.

  According to the wafer ID reading apparatus and the wafer ID reading method of the present invention, when a plurality of semiconductor wafers having identification information written at positions where the distances from the positioning notches are equal are taken out from the storage body and arranged at the reference position, The control unit controls the rotation of the wafer holding unit based on the distance data so that the identification information falls within the imaging area of the image acquisition unit. For this reason, the movement of the semiconductor wafer with respect to the image acquisition means can be minimized, and the identification information of a plurality of semiconductor wafers can be read in a short time.

1 to 6 show an embodiment according to the present invention, and the embodiment described here is applied to a substrate inspection apparatus for performing a defect inspection process for a device pattern formed on a surface of a semiconductor wafer. If included.
As shown in FIG. 1, a wafer cassette (housing body) 3 is disposed adjacent to the substrate inspection apparatus 1. In the wafer cassette 3, a plurality of slots are provided in the vertical direction for storing the semiconductor wafers S one by one. By storing the semiconductor wafers S in the slots, the plurality of semiconductor wafers S are predetermined in the vertical direction. It will be stored at the pitch.
The substrate inspection apparatus 1 includes an inspection unit 5 that inspects the semiconductor wafer S, and a loader unit 7 that transports the semiconductor wafer S between the wafer cassette 3 and the inspection unit 5.

The loader unit 7 is configured to detachably attach a plurality (two in the illustrated example) of wafer cassettes 3, and a wafer transfer robot 11 that reciprocates between these wafer cassettes 3 by a shift mechanism 9. I have. The shift mechanism 9 moves the wafer transfer robot 11 in one direction between a position where the semiconductor wafer S is transferred to / from each wafer cassette 3 and a position where the semiconductor wafer S is transferred to / from the inspection unit 5. It is reciprocated in the (C direction).
The wafer transfer robot 11 is a so-called articulated robot, and includes a rotating shaft 13, a plate-like hand 15 on which the semiconductor wafer S is placed, and three connecting arms that connect the rotating shaft 13 and the hand 15 to each other. 17-19.

  That is, one end of the first connecting arm 17 is rotatably connected to the rotary shaft 13, and the other end of the first connecting arm 17 is mutually connected with one end of the second connecting arm 18. It is connected rotatably. The other end of the second connecting arm 18 is rotatably connected to one end of the third connecting arm 19, and the hand 15 holding the semiconductor wafer S on the other end of the third connecting arm 19. Is fixed. Therefore, by appropriately rotating these three connecting arms 17 to 19, the distance from the rotary shaft 13 to the hand 15 is changed, that is, the wafer transfer robot 11 is expanded and contracted.

A plurality of suction holes 21 are formed on the surface of the hand 15, and these suction holes 21 communicate with a suction pump (not shown). That is, by operating the suction pump while the semiconductor wafer S is placed on the surface of the hand 15, the semiconductor wafer S is sucked and held on the hand 15 by the suction force of the suction pump.
Since the loader unit 7 is configured as described above, the hand 15 can be moved between each wafer cassette 3 and the wafer loading position P <b> 1 in the inspection unit 5. The wafer carry-in position P1 indicates a position where the semiconductor wafer S is delivered between the wafer transfer robot 11 and the inspection unit 5.

The inspection unit 5 includes three arms that circulate and convey the semiconductor wafer S between the well-known macro inspection unit 23 and micro inspection unit 25 and the wafer carry-in position P1, macro inspection position P2, and micro inspection position P3 of the inspection unit 5. And a rotary conveyance unit 27.
The micro-inspection unit 25 sucks and holds the semiconductor wafer S and rotates the position detection sensor 29 for alignment provided at the wafer transfer position P3 with the rotary conveyance unit 27, the microscope 31 for enlarging the image of the semiconductor wafer S, and the rotation. A wafer holding unit 33 having a mechanism, and an XY stage (moving means) 35 for moving the wafer holding unit 33 two-dimensionally between the wafer delivery position P3 and a predetermined observation position of the microscope 31 are provided.

The position detection sensor 29 is constituted by, for example, a CCD camera. After the semiconductor wafer S is transferred from the rotary transfer unit 27 to the wafer holding unit 33 at the wafer transfer position P3 with the rotary transfer unit 27, the wafer is detected. The semiconductor wafer S is rotated by the wafer holder 33 at the delivery position P3, and two or more edge positions (coordinate data) of the semiconductor wafer S are detected. This detection result is edge position information of two or three points that does not lie on the orientation flat of the semiconductor wafer S, and the center deviation amount of the semiconductor wafer S with respect to the normal position of the semiconductor wafer S in the wafer holder 33 is obtained. This is used to correct the center deviation of S. The alignment at the wafer delivery position P3 has a higher accuracy than the pre-alignment at the wafer carry-in position P1 described later.
In the micro inspection unit 25, an image of the semiconductor wafer S magnified by the microscope 31 can be imaged by an imaging device 37 such as a CCD camera or can be observed through an eyepiece lens 39.

  The rotary conveyance unit 27 rotates about the rotation shaft 41 (counterclockwise in the illustrated example), and includes three rotation arms 43 a to 43 c extending from the rotation shaft 41 in the orthogonal direction. These three rotary arms 43a to 43c are arranged at equal angles (for example, every 120 degrees) around the rotary shaft 41. The three rotary arms 43 a to 43 c are connected to the wafer carry-in position P <b> 1 for delivery with the wafer transfer robot 11, the macro inspection position P <b> 2 for performing macro inspection by the macro inspection unit 23, and the semiconductor wafer S to the micro inspection unit 25. Rotate and circulate between the wafer transfer positions P3.

  At the tips of the rotating arms 43a to 43c, substantially L-shaped hands 44a to 44c that hold the semiconductor wafer S by suction are provided. A plurality of suction holes 21 are formed on the surfaces of the hands 44a to 44c, and these suction holes 21 communicate with a suction pump (not shown). That is, by operating the suction pump in a state where the semiconductor wafer S is placed on the surfaces of the hands 44a to 44c, the semiconductor wafer S is sucked and held on the hands 44a to 44c by the suction force of the suction pump.

  A plurality (four in the illustrated example) of position detection sensors 45 to 48 for pre-alignment of the semiconductor wafer S are provided at the wafer carry-in position P1. The position detection sensors 45 to 48 are constituted by, for example, line sensors or two-dimensional CCD cameras, and the centers of the position detection sensors 45 to 48 are arranged on concentric circles having the same size as the semiconductor wafer S. Further, the position detection sensors 45 to 48 are arranged at intervals larger than the length of the orientation flat of the semiconductor wafer S. These position detection sensors 45 to 48 detect the four edge positions (coordinate data) of the semiconductor wafer S by an image when the semiconductor wafer S is transferred from the wafer transfer robot 11 to the rotating arms 43a to 43c. is there.

The edge position information of the four points is used to obtain the center deviation amount of the semiconductor wafer S with respect to the normal position of the semiconductor wafer S at the wafer carry-in position P1 of the rotary conveyance unit 27 and correct the center deviation of the semiconductor wafer S. .
The center deviation correction at the wafer carry-in position P <b> 1 may be performed as long as accurate alignment is possible in the micro inspection unit 25. For this reason, the pre-alignment apparatus at the wafer carry-in position P1 may have a mechanical configuration that corrects the center deviation of the semiconductor wafer S, for example, by pinching the edge of the semiconductor wafer S with pins at least at three locations.

The inspection unit 5 is provided with a control unit 51 that controls the operations of the wafer transfer robot 11 and the rotary transfer unit 27 and various operations in the macro inspection and micro inspection in the inspection unit 5.
The control unit 51 includes an operation unit 53 for the inspector M to operate various operations and various settings in the loader unit 7 and the inspection unit 5, and an enlarged image of the semiconductor wafer S captured by the imaging device 37 and the like described above. And a monitor 55 for displaying the above. The control unit 51 also has a function for controlling alignment at the wafer carry-in position P1 and the wafer delivery position P3.

That is, the control unit 51 is based on the detection results of the position detection sensors 45 to 48 arranged at the wafer carry-in position P1 of the inspection unit 5 and the position detection sensor 29 arranged at the wafer delivery position P3 with the wafer holding unit 33. Then, the deviation amount of the center deviation and the angular deviation of the semiconductor wafer S with respect to the normal position is calculated.
Further, the control unit 51 controls the movement of the wafer transfer robot 11 on which the semiconductor wafer S is placed in the X and Y directions according to the calculated deviation amount so as to correct the semiconductor wafer S to the center position of the wafer loading position P1. At the same time, the wafer holding unit 33 is controlled to move in the X and Y directions by the XY stage 35 in accordance with the calculated deviation amount, and the center position of the wafer holding unit 33 is accurately corrected to the center position of the semiconductor wafer S.
Further, the control unit 51 controls the rotation of the wafer holding unit 33 according to the calculated amount of angular deviation, and corrects the angle of the semiconductor wafer S with respect to the microscope 31. That is, the amount of angular deviation of the notch N with respect to the reference position in the rotation direction of the semiconductor wafer S in the microscope 31 is obtained, and the wafer holder 33 is rotated based on the amount of angular deviation to align the notch N with the reference position.

  At the wafer delivery position P3 of the micro inspection unit 25, a wafer ID imaging module (image acquisition means) 57 for reading the wafer ID written on the edge portion of the surface of the semiconductor wafer S is provided. As shown in FIGS. 2 and 3, the wafer ID imaging module 57 includes an irradiation unit 59 that irradiates illumination light toward an imaging region located at an edge portion of the surface Sa of the semiconductor wafer S, and reflected light from the imaging region. And an imaging unit 61 that receives the light and acquires an enlarged image of the imaging region. The irradiation unit 59 is configured so that an angle (irradiation angle) θ1 between the surface Sa of the semiconductor wafer S and the optical axis of the irradiation light can be arbitrarily set.

The imaging unit 61 includes a one-dimensional CCD (line sensor camera), and images the edge portion of the semiconductor wafer S rotated at a constant rotational speed by the wafer holding unit 33 in synchronization with the rotational speed of the wafer holding unit 33. Thus, an image of the edge portion is acquired. Therefore, the semiconductor wafer S is rotated by the wafer holding unit 33, and the notch N that is a positioning notch formed at the edge portion of the semiconductor wafer S and the identification information (wafer ID) W are set in the imaging region of the imaging unit 61. By passing it, the notch N identification information W can be imaged.
In addition, the imaging unit 61 has a function of detecting a defect at the edge portion of the semiconductor wafer S, a notch N, and identification information W, and the semiconductor wafer according to a detection condition for the defect at the edge portion and the identification information W. An angle (imaging angle) θ2 between the surface Sa of S and the optical axis of the imaging unit 61 is configured to be arbitrarily set.
The imaging unit 61 also serves as a position detection sensor that detects the positioning notch (notch N) by rotating the semiconductor wafer S by the wafer holding unit 33.

The illumination unit 59, the imaging unit 61, and the wafer holding unit 33 of the micro inspection unit 25 are connected to a control unit (control unit) 63 of the control unit 51. The control unit 63 is connected to an operation unit 53 and a monitor 55 and a memory unit (storage unit) 65 for storing various data such as identification information.
The control unit 63 obtains a distance from the center position of the notch N of the semiconductor wafer S to the notation position of the identification information W based on the detection result of the notch N and the identification information W in the imaging unit 61 in advance, and the distance data and the semiconductor Reference position data in the rotation direction of the wafer S is stored in the memory unit 65.
That is, the control unit 63 controls the rotation of the wafer holding unit 33, obtains the amount of angular deviation from the rotation position of the wafer holding unit 33 to the reference position when the imaging unit 61 detects the notch N, and uses the notch N as a reference. Adjust to position. Then, the control unit 63 rotationally moves the semiconductor wafer S from this reference position in one direction by the wafer holding unit 33, and from the rotation angle of the wafer holding unit 33 when the imaging unit 61 detects the identification information W to the reference position. Find the distance.

Further, the control unit 63 adjusts the amount of reflected light received by the imaging unit 61, the irradiation angle θ1 of the illumination unit 59, and the imaging angle θ2 of the imaging unit 61 to be appropriate optical conditions for reading the identification information W. The operations of the illumination unit 59 and the imaging unit 61 are controlled. In addition, there are methods for reading the identification information W that correspond to the respective types of characters, symbols, patterns, and the like that represent the identification information, and the control unit 63 sets an appropriate method for reading each type of the information. .
These rotation angles and reading conditions are stored in the memory unit 65 as recipe information.

In addition, the control unit 63 performs image processing on the enlarged image captured by the imaging unit 61 and reads the identification information W. That is, for example, when the identification information W written on the semiconductor wafer S is a character composed of alphabets, numbers, etc., the enlarged image acquired by the control unit 63 is appropriately subjected to image processing, and the identification information W is converted into character data. Recognize as
The identification data of the read identification information W is stored in the memory unit 65 in association with each slot of the wafer cassette 3 that stores the semiconductor wafer S.

Further, when detecting the notch N of each semiconductor wafer S taken out from the wafer cassette 3, the control unit 63 reads recipe information from the memory unit 65, and based on this recipe information, the wafer holding unit 33, the irradiation unit 59, and The operation of the imaging unit 61 is controlled, and the identification information W imaged by the imaging unit 61 is subjected to image processing to read edge defects and identification information W of the semiconductor wafer S. Here, the control unit 63 rotates the rotation direction and rotation amount (rotation angle) of the wafer holding unit 33 so that the rotation amount of the wafer holding unit 33 with respect to the reference position is minimized when the identification information W is imaged by the imaging unit 61. ) And the operation of the wafer holding unit 33 is controlled.
In the above operation, when the identification information W is not detected by the imaging unit 61, the control unit 63 sets the optical conditions and the reading conditions again and stores them in the memory unit 65 as other recipe information.

As shown in FIG. 4, the screen of the monitor 55 is provided with an image display area 71 for displaying an enlarged image captured by the imaging unit 61 and an identification data display column 73 for displaying the above-described identification data. In the identification data display column 73, the identification data of the semiconductor wafer S read by the imaging unit 61 is displayed.
If the control unit 63 recognizes the identification information W by mistake or fails to recognize the identification information W, the inspector M visually recognizes the identification information W displayed in the image display area 71 and operates the operation unit 53. The identification information W can be input to the identification data display field 73.

In addition, the monitor 55 is provided with an identification data list display area 75 for displaying identification data corresponding to the slot number (1 to 25 in the illustrated example) indicating the storage position of each semiconductor wafer S in the wafer cassette 3. ing. The color of each column of the identification data list display area 75 for displaying the identification data changes before and after the identification data is read, and the identification data reading state of each semiconductor wafer is changed for each wafer cassette 3. Can be identified.
The identification information W of the semiconductor wafer S is read by the wafer ID imaging module 57, the control unit 63, the memory unit 65, the wafer holding unit 33 of the micro inspection unit 25, the operation unit 53 and the monitor 55 of the control unit 51. A wafer ID reading unit (wafer ID reading device) is configured.

Next, the operation of the substrate inspection apparatus 1 configured as described above will be described.
Here, recipe information for reading the identification information is created before the defect inspection of the semiconductor wafer S is performed. That is, as shown in FIG. 5, the semiconductor wafer S accommodated in the wafer cassette 3 is transferred by the wafer transfer robot 11 and the rotary transfer unit 27 via the macro inspection unit 23 to the wafer transfer position P3 of the micro inspection unit 25. (Step S1).
Then, alignment correction is performed based on the detection result of the edge position of the semiconductor wafer S detected by the position detection sensor 29 of the micro inspection unit 25 (step S2). Next, the notch N of the semiconductor wafer S is detected by the wafer ID imaging module 57, and the notch N is adjusted to the reference position (step S3). These steps S1 to S3 show a process of taking out a plurality of semiconductor wafers S from a wafer cassette 3 and storing them at a reference position.

Thereafter, the wafer holding unit 33 is rotated in one direction from the reference position, and based on the rotation angle of the wafer holding unit 33 when the identification information W (wafer ID) is detected by the imaging unit 61, the position of the identification information W is determined. The distance to the reference position is obtained (step S4).
Then, the optical unit appropriate for reading the identification information W is adjusted by operating the illumination unit 59 and the imaging unit 61 (step S5), the distance (rotation angle) from the reference position to the identification information W, the optical condition, and the like. Are stored in the memory unit 65 as recipe information (step S6), and the creation of recipe information for reading the identification information is completed.

  Then, after completion of the recipe information creation, the semiconductor wafer S is inspected for defects. That is, an uninspected semiconductor wafer S is taken out of the wafer cassette 3 by the wafer transfer robot 11 and transferred to the wafer carry-in position P1 where the semiconductor wafer S is transferred to and from the hands 44a to 44c of the rotary transfer unit 27. When the semiconductor wafer S is arranged at the wafer carry-in position P1, the center deviation of the semiconductor wafer S with respect to the hands 44a to 44c is based on the detection result of the edge position of the semiconductor wafer S detected by the position detection sensors 45 to 48. The amount of deviation is calculated. Then, the wafer transfer robot 11 is moved based on the amount of deviation, and the center deviation of the semiconductor wafer S with respect to the hands 44a to 44c is roughly corrected.

  After completion of the correction, the semiconductor wafer S is transferred from the wafer transfer robot 11 to the hands 44a to 44c of the rotary transfer unit 27, and moves from the wafer carry-in position P1 to the macro inspection position P2 by the rotation of the rotary transfer unit 27. Then, the semiconductor wafer S is transferred from the hands 44 a to 44 c to the macro inspection unit 23, and the macro inspection of the semiconductor wafer S is performed in the macro inspection unit 23. After completion of the macro inspection, the semiconductor wafer S is transferred from the macro inspection section 23 to the hands 44a to 44c, and the wafer between the macro inspection position P2 and the micro inspection section 25 is rotated by the rotation of the rotary conveyance section 27 as shown in FIG. It moves to the delivery position P3 (step S11).

Then, similarly to step S2 described above, high-precision alignment correction is performed based on the detection result of the edge position of the semiconductor wafer S detected by the position detection sensor 29 of the micro inspection unit 25, and the semiconductor wafer S is moved to the wafer holding unit. It arrange | positions to the regular position of 33 (step S12). Further, similarly to step S3, the notch N of the semiconductor wafer S is detected by the wafer ID imaging module and is adjusted to the reference position (step S13).
Thereafter, the wafer holding unit 33 is rotated based on the recipe information stored in the memory unit 65 or the illumination unit 59 and the imaging unit 61 are operated, and the imaging unit 61 enlarges the image of the semiconductor wafer S including the identification information W. And the identification information W is read as identification data based on the enlarged image (step S14). The obtained enlarged image and identification data are displayed on the monitor 55 (step S15), and based on the identification data, it is determined whether or not the control unit 63 is a semiconductor wafer S to be inspected for micro inspection (step S16). ).

Here, when the control unit 63 determines that the semiconductor wafer S is an inspection target, the XY stage 35 is scanned in a direction along the surface of the semiconductor wafer S, and the microscope 31 expands the semiconductor wafer S. A micro inspection for displaying an enlarged image on the monitor 55 or observing through the eyepiece lens 39 is performed (step S17). After this inspection, the semiconductor wafer S is transferred from the wafer transfer position P3 with the micro inspection unit 25 to the wafer cassette 3 by the wafer transfer robot 11 and the rotary transfer unit 27 (step S18), and the defect inspection of the semiconductor wafer S is completed. To do.
If the controller 63 determines in step S16 that the semiconductor wafer S is not the inspection target, step S18 is performed without performing step S17, and the defect inspection of the semiconductor wafer S is completed.
Note that the operations in steps S11 to S18 are sequentially performed in the same manner on the same types of semiconductor wafers S stored in the wafer cassette 3.

As described above, according to the wafer ID reading unit and the wafer ID reading method provided in the substrate inspection apparatus 1, the same type of semiconductor wafer S in which the identification information W is written at the position where the movement amount from the reference position is equal. Is taken out from the wafer cassette 3 and placed at the reference position of the wafer holding unit 33, the surface Sa of the semiconductor wafer S including the identification information W based on the recipe information stored in the memory unit 65 becomes the surface of the wafer ID imaging module 57. The wafer holding unit 33 moves the semiconductor wafer relative to the image acquisition means so as to enter the imaging region. For this reason, the movement of the semiconductor wafer S with respect to the wafer ID imaging module 57 can be minimized.
Also, every time the identification information W of each semiconductor wafer S is read, the operation of the illumination unit 59 and the imaging unit 61 is controlled so that the appropriate reading conditions for reading the identification information W based on the recipe information are obtained. There is no need to adjust. Therefore, the identification information W of the plurality of semiconductor wafers S can be read in a short time.

Furthermore, since the enlarged image of the semiconductor wafer S including the identification information W and the identification data are displayed on the monitor 57, the extracted identification data and the enlarged image including the identification information W can be viewed at the same time. It is possible to reliably prevent erroneous reading.
In particular, the substrate inspection apparatus 1 can correctly recognize the written identification information W, so that the inspection of the semiconductor wafer S not subject to inspection can be reliably prevented and the inspection efficiency of the semiconductor wafer S can be improved. it can.
Further, since the monitor 55 is provided with the identification data list display area 75, the reading state of the identification information of each semiconductor wafer can be identified for each wafer cassette 3, and the inspector M can identify the identification information W for each wafer cassette 3. The progress of reading can be easily grasped.

In the above embodiment, the imaging unit 61 is composed of a one-dimensional CCD (line sensor camera). However, at least the surface Sa of the semiconductor wafer S is enlarged and imaged, and the notch N and the identification information W are displayed. Any device can be used as long as it can be detected, for example, a two-dimensional CCD sensor or a time delay camera (TDI camera).
In addition, the detection of the positioning notch formed in the edge portion of the semiconductor wafer S is performed in the imaging unit 61, but the present invention is not limited to this. For example, a position detection sensor disposed at the wafer delivery position P3 29 may be performed. In this configuration, when the position detection sensor 29 detects the notch N, the detection result may be output to the control unit 63. In the above configuration, the position detection sensor 29 is also included in the configuration of the wafer ID reading unit as a part of the wafer ID imaging module 57.

Further, the position of the notch N of the semiconductor wafer S is set as a reference position for detecting the notation position of the identification information W. However, the present invention is not limited to this. For example, for positioning formed at the edge portion of the semiconductor wafer S The center position of the orientation flat may be used as the reference position as the notch.
Further, the wafer ID imaging module 57 is configured to image the identification information W written on the front surface Sa of the semiconductor wafer S. However, the present invention is not limited to this, and is formed on the back surface of the semiconductor wafer S. The identification information W may be configured to be imaged.

  Further, the wafer ID imaging module 57 is arranged at the wafer delivery position P3. However, the present invention is not limited to this, and at least a wafer holding unit provided with a rotating mechanism for horizontally placing and rotating the semiconductor wafer S. I just need it. For example, an aligner for performing separate alignment may be newly provided in the semiconductor wafer processing apparatus such as the substrate inspection apparatus 1 or the exposure apparatus, and the wafer ID imaging module 57 may be provided on the aligner.

  Further, the identification data extracted from the enlarged image is not limited to being used for display on the monitor 55 and determination of necessity of micro inspection. That is, for example, when the identification data of each semiconductor wafer S accommodated in each slot of the wafer cassette 3 is known in advance, the identification data extracted from the enlarged image is controlled with the identification data corresponding to the predetermined slot number. You may make it contrast in the part 63. FIG. In this case, erroneous recognition of identification data by the control unit 63 can be reliably prevented.

Furthermore, the semiconductor wafer S is transferred to the wafer cassette 3 after executing step S6 for storing the recipe information of the semiconductor wafer S in the memory unit 65. However, the present invention is not limited to this. For example, each of steps S14 to S17 is performed. The semiconductor wafer S may be transferred to the wafer cassette 3 after appropriately performing the process.
Although the identification information W is read after the macro inspection is completed, the present invention is not limited to this, and the identification information W may be read before the macro inspection. In this case, the inspection efficiency of the semiconductor wafer S in the substrate inspection apparatus 1 can be further improved.
Furthermore, although the wafer ID reading unit is included in the substrate inspection apparatus 1, the present invention is not limited to this. For example, the wafer ID reading unit may be included in a semiconductor wafer processing apparatus such as an exposure apparatus for manufacturing a semiconductor, or alone. A wafer ID reader may be configured.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the concrete structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.

It is a schematic plan view which shows the board | substrate inspection apparatus which concerns on one Embodiment of this invention. It is a schematic perspective view which shows the structure of the wafer ID reading unit contained in the board | substrate inspection apparatus of FIG. It is a block diagram which shows the circuit structure of the board | substrate inspection apparatus of FIG. FIG. 3 is a diagram showing a monitor screen on which an enlarged image and identification data of a semiconductor wafer are displayed in the wafer ID reading apparatus of FIG. 2. 2 is a flowchart showing a procedure for creating recipe information for reading identification information in the substrate inspection apparatus of FIG. 1. 2 is a flowchart illustrating a semiconductor wafer inspection procedure in the substrate inspection apparatus of FIG. 1.

Explanation of symbols

3 Wafer cassette (container)
29 Position Detection Sensor 33 Wafer Holding Unit 57 Wafer ID Imaging Module (Image Acquisition Unit)
61 Imaging unit (position detection sensor)
63 Control unit (control means)
65 Memory part (storage means)
S Semiconductor wafer N Notch (notch for positioning)
W Identification information

Claims (5)

A wafer ID reader for reading identification information written on an edge portion of the semiconductor wafer taken out from a storage body containing a plurality of semiconductor wafers,
A wafer holding unit for holding and rotating the semiconductor wafer taken out from the storage body;
Image acquisition means for imaging an edge portion of the semiconductor wafer held by the wafer holding unit;
A position detection sensor for detecting a positioning notch formed in an edge portion of the semiconductor wafer;
A distance from the center position of the positioning notch detected by the position detection sensor to the notation position of the identification information imaged by the image acquisition means is obtained, and the identification information is obtained based on this distance. And a control means for controlling the rotation of the wafer holder so as to be positioned at the imaging position.   The control means obtains a distance from a center position of the positioning notch detected by the position detection sensor to a notation position of the identification information imaged by the image acquisition means, and the distance data and the semiconductor wafer 2. The wafer ID reading apparatus according to claim 1, wherein a reference position in the rotation direction is stored in advance in a storage means.   The control unit reads the distance data from the storage unit every time the semiconductor wafer taken out from the storage body is arranged at the reference position, and the identification information is based on the distance data based on the distance data. The wafer ID reading apparatus according to claim 2, wherein the wafer holding unit is rotationally controlled so as to be positioned on the wafer ID.   4. The wafer ID reading apparatus according to claim 1, wherein the image acquisition unit also serves as the position detection sensor. 5. A step of taking out a plurality of semiconductor wafers from a storage body and transporting them to a wafer holder;
Rotating the semiconductor wafer held by the wafer holding unit, and imaging the identification information written on the edge portion of the semiconductor wafer by an image acquisition unit;
Rotating the semiconductor wafer held by the wafer holding unit and detecting a positioning notch formed in an edge portion of the semiconductor wafer by a positioning sensor;
Obtaining a distance from a center position of the positioning notch detected by the position detection sensor to a notation position of the identification information imaged by the image acquisition means, and storing the distance data in a storage means;
Each time each semiconductor wafer taken out from the storage body is placed at the reference position, the distance data is read from the storage means, and the wafer holding unit is rotationally controlled based on the distance data to obtain the identification information. A wafer ID reading method comprising: positioning at an imaging position of the image acquisition means.

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