JP2005260173A - Part bonding method and bonding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a bonding in which a relative position between a chip part in which a large number of electrode parts are arranged at high density and an object to be mounted are positioned with high accuracy and each corresponding electrode is directly joined to each other. Provided are a component bonding method and a bonding apparatus that can be performed without any problems.
SOLUTION: A chip component 2 is corrected to a posture facing a mounting object 4 in parallel based on a flatness correction amount calculated from the result of image processing of image data at a plurality of locations on a side peripheral surface of the chip component 2. 1 and a second step of positioning the chip component 2 and the mounting object 4 at a predetermined relative position based on the relative displacement correction amount calculated from the image processing result of the image data of the positioning marks 2c and 4c. And a third step of joining the respective electrode parts 2b, 4b of the chip part 2 and the mounting object 4 by superposing and pressing each other in a vacuum atmosphere or an atmosphere that is not oxidized.
[Selection] Figure 4

Description

  The present invention is suitably used for a next-generation mounting method, for example, directly bonding a bumpless chip component such as an IC just separated from a wafer through a scribing process to a mounting object such as a circuit board. The present invention relates to a bonding method and bonding apparatus for parts that can be produced.

  In recent years, electronic devices have been required to be smaller and lighter. Accordingly, in order to increase the mounting density of electronic circuits, a semiconductor bare chip obtained by dividing a wafer into pieces is turned over and directly mounted on a circuit board. The flip chip mounting method is often used. For example, what is produced by the flip chip mounting method includes CSP (Chip Size Package) that packages the same size as the semiconductor bare chip and MCM (Multi Chip Module) that mounts multiple semiconductor bare chips on a circuit board. Production by these is increasing.

  In the SBB (Stud Bump Bonding) method, which is one of the flip chip mounting methods, a bump (projection) is formed on each of a plurality of electrode pad portions arranged on a semiconductor bare chip by applying a wire bonding method. On the other hand, a plurality of patterned substrate electrodes are formed on a circuit board, which is a semiconductor bare chip mounting target, and ultrasonic waves are applied to the bumps while applying pressure to the semiconductor bare chip with each bump in contact with the substrate electrode. The bump and the substrate electrode are bonded by ultrasonic bonding that imparts or adhesive bonding method that applies an adhesive to the bump.

  Conventionally, the chip component is placed at a desired position on the mounting target, and the chip component is bonded so that the bonding surfaces of the chip component and the mounting target can be uniformly contacted. A method and a bonding apparatus have also been proposed (see Patent Document 1).

In the bonding method, the chip component and the mounting object are overlapped with each other in a state where the chip component and the mounting object are positioned at a predetermined relative position in the bonding position. It is arranged in two directions perpendicular to each other, and the above-described two imaging means are used to photograph the bright and dark parts due to the transmitted light in the gaps generated between the bonding surfaces due to the poor parallelism between the chip component and the mounting object. Image data is image-processed to detect the parallelism between the bonding surfaces, and the relative angular position of the chip component and the mounting object is set within the allowable range according to the detected parallelism. After the adjustment, the chip component is joined to the mounting object.
JP 2002-217216 A

  However, as the density of the substrate increases in the future, the joints are also becoming finer. As a result, the bumps themselves must be miniaturized. However, there is a limit to the miniaturization of bumps, and a bumpless method is expected. In particular, since the circuit pattern tends to be further densified in the future, in that case, the increase in the above-described conductive resistance becomes more significant, which may cause troubles such as malfunction of the circuit. .

  Therefore, in the near future, for example, a so-called next-generation mounting method will be adopted, such as directly bonding a so-called bumpless chip component that has just been separated from the wafer through a scribe process to a mounting object such as a circuit board. Is very likely. However, when the bumpless chip component is directly bonded to the circuit board, the following new problem may occur.

  That is, when bonding the bumpless chip component described above directly to the circuit board, the surface of each electrode part of the chip component and the circuit board is cleaned and then pressed in a vacuum atmosphere or an atmosphere that does not oxidize. Therefore, it is generally considered that a means for directly joining the electrode parts to each other by the law of intermetallic bonding is adopted. When bonding a chip component to a mounting object via a conventional bump, even if there is a variation in parallelism between the chip component and the mounting object, this variation can be absorbed by the bump. However, when the electrode parts are directly joined to each other according to the above-mentioned law of metal-to-metal bonding, both of the small electrode parts arranged at high density are positioned at an accurate relative position and slightly different from each other. It is a precondition that the contact state is completely free of gaps. If bonding is performed according to the law of metal-to-metal bonding in a state where this condition is not satisfied, problems such as a decrease in bonding strength and an increase in the conductive resistance of the bonding portion occur.

  On the other hand, since there are deformations, distortions, distortions, and undulations in the bonding surfaces of the chip part and the mounting object when viewed macroscopically, the above-described chip part and mounting object have a high level. In order to place all of the relatively large number of electrode parts arranged in the density at the exact relative positions where they match each other and make complete contact without gaps, the chip component and the mounting object are on the order of several μm. It is necessary to position with high accuracy so that parallelism can be obtained. However, in the conventional bonding method, a bright and dark portion by a transmitted light in a gap formed between the bonding surfaces of the chip component and the mounting target object positioned at predetermined relative positions and overlapped with each other is photographed. Image data is image-processed to detect the parallelism between the bonding surfaces, and the relative angular position of the chip component and the mounting object is set within the allowable range according to the detected parallelism. Since the adjustment is made, it is impossible for such positioning means to completely bring the chip component and the mounting object into contact with each other at the above-described accurate relative position without a gap.

  Moreover, conventionally, positioning of the relative position is performed based on the amount of relative displacement calculated based on the image processing of the image data obtained by imaging the positioning mark attached to each of the chip component and the mounting target with the camera. When the positioning mark is photographed in a state where the chip part and the mounting object are not facing each other with an accurate parallelism, the positioning mark detection position calculated by image processing is inaccurate. Therefore, it becomes difficult to position the chip component and the mounting target object at an accurate relative position. Furthermore, since the angle adjustment for correcting the parallelism between the chip component positioned at the predetermined relative position and the mounting target is performed, the relative position once corrected at the time of the angle adjustment is easily shifted. Therefore, the conventional bonding technique cannot be adopted when directly bonding the bumpless chip component described above to the circuit board.

  The present invention has been made in view of the above-described conventional problems. The relative position between a chip component in which a large number of electrode portions are arranged at a high density and a mounting object are positioned with high accuracy, and each of the corresponding parts is provided. It is an object of the present invention to provide a component bonding method and a bonding apparatus capable of performing bonding without interfering directly with electrodes.

  In order to achieve the above object, the component bonding method according to the first aspect of the present invention is directed to the chip component and the mounting target when the electrode portions of the chip component are directly bonded to the corresponding electrode portions of the mounting target. The chip component is attached to the mounting object based on the flatness correction amount calculated from the result of image processing of image data obtained by photographing a plurality of locations on the side peripheral surface of the chip component from the side in a state of being separated from each other. A first step of correcting the posture to be opposed to each other in parallel, and the chip processing and the mounting object that are opposed to each other in parallel to each other, and image processing of image data obtained by photographing the positioning marks respectively attached thereto The second step of positioning at a predetermined relative position based on the relative displacement correction amount calculated from the result, the chip component positioned at the predetermined relative position, and the mounting object are By pressurizing by polymerizing with each other or in an atmosphere that does not oxidize in the atmosphere, it is characterized by having a third step of joining the electrode portions of each of said chip component and the mounting object.

  According to a second aspect of the present invention, in the first step of the first aspect of the present invention, while rotating the bonding head that holds the chip component, the side peripheral surface of the chip component is photographed with a single imaging means, The tilt amount and tilt direction of the chip component are calculated as the flatness correction amount from the height difference of the chip component in the image data obtained by this shooting, and the posture of the chip component is corrected based on the calculated flatness correction amount. did.

  According to a third aspect of the present invention, in the first step of the second aspect of the invention, in addition to correcting the posture of the chip component based on the flatness correction amount, the movable holding base for holding the mounting object is rotated. However, the side circumferential surface of the mounting object is photographed by a single imaging means, and the amount of inclination and the tilt direction of the mounting object are corrected for flatness from the height difference of the mounting object in a plurality of image data obtained by this photographing. It was calculated as a quantity, and based on the calculated flatness correction quantity, the mounting object was corrected to a posture facing the chip component in parallel.

  According to a fourth aspect of the present invention, in the third step of the invention according to any one of the first to third aspects, the chip component is superposed on a mounting object by an operation of a bonding head that holds the chip component, Release the holding of the chip component by the bonding head, and the chip component and the mounting object in a superposed state, and a rotation pressing portion that is provided in the bonding and presses the chip component against the mounting object with a predetermined pressure. The chip component is pressed against the mounting target object with the predetermined pressure over the entire surface by the rotary pressing portion that is relatively moved and rotates on the surface of the chip component.

  According to a fifth aspect of the present invention, in the third step of the fourth aspect of the invention, when the chip component is superposed on a mounting object by the operation of the bonding head, the chip component is rotated by the rotation pressing portion of the bonding head. At least one of the electrode portions is pressed against the corresponding electrode portion of the mounting object with a predetermined pressure so as to be bonded to each other according to the law of metal-to-metal bonding.

  According to a sixth aspect of the present invention, there is provided a component bonding apparatus comprising: a holding mechanism that detachably holds a chip component; and a rotary pressing portion that presses the chip component against an object to be mounted with a predetermined pressure. A bonding head, a component rotation drive source for rotating the bonding head, a pressurization control drive source for pressurizing the rotation pressing portion with a predetermined pressure, and an inclination angle with respect to a horizontal plane with respect to the holding mechanism. An adjustable component flatness adjusting mechanism, a holding table for holding the mounting object in an arrangement opposite to the chip component, and a moving mechanism for moving at least one of the bonding head or the holding table in a horizontal direction; A side peripheral surface of the chip component rotated by driving of the component rotation drive source while being held by the bonding head is laterally viewed. A first imaging means for shadowing; a second imaging means for photographing the positioning marks respectively attached to the chip component and the mounting object facing each other in a separated state; and the first and second imaging means, respectively. An image processing unit that performs image processing on the captured image data to calculate a flatness correction amount of the chip component and a relative positional deviation correction amount between the chip component and the mounting object, and a flatness calculated by the image processing unit Based on the correction amount and the relative positional deviation amount correction, the component flatness adjusting mechanism and the movement mechanism are respectively controlled to correct the chip component to a posture parallel to the mounting target, and then the chip component. And the mounting object are positioned at a predetermined relative position, the chip component is superposed on the mounting object, and the moving mechanism is operated to activate the superposition state. Tsu is the control to the control means such that flops parts and relative movement between the mounting object and the rotary pressing portion, characterized in that it comprises a.

In the first aspect of the invention, the position of each positioning mark between the chip component and the circuit board is detected in a state where the posture is corrected so that the chip component is parallel to the mounting target, and the relative positional deviation amount is calculated. After the calculation, the chip component and the mounting target are aligned based on the relative positional deviation correction amount, so that the chip component and the mounting target can be positioned at an extremely accurate relative position on the order of 0.1 μm. . Therefore, in this bonding method, even if the chip part is a chip part in which a large number of electrode parts are arranged at high density, all of the chip part and each of the many electrode parts of the mounting object are accurately matched to each other. It is possible to perform positioning, and it is possible to perform bonding without interfering directly with the corresponding electrode portions of the chip part and the mounting target. In the invention of claim 2, only a single imaging means is provided. With this simple configuration, it is possible to image the side peripheral surface of the chip component with this single imaging means, and the chip component is mounted based on the correction amount calculated from the result of image processing of this relatively large amount of image data The posture can be corrected so as to be exactly parallel to the object.

  In the invention of claim 3, in addition to correcting the flatness of the component, the correction calculated from the result of image processing of a relatively large amount of image data obtained by imaging the side peripheral surface of the mounting object by a single imaging means. Since the flatness of the mounting object is also corrected based on the amount, the correction for arranging the chip component and the mounting object in parallel with each other can be performed with higher accuracy.

  In the invention of claim 4, even if the chip component is deformed, distorted, distorted, or undulated, all of the multiple electrode portions arranged at high density in the chip component are each corresponding to the mounting object. Since the electrode parts can be bonded to each other in a tight contact state without gaps, the chip component is bonded to the mounting object with high bonding strength, and the conductive resistance between the electrode parts of both the chip part and the mounting object is reduced. It can be greatly reduced.

  In the invention of claim 5, at the time when the chip component is overlaid on the mounting object, at least the specific electrode part facing the rotation pressing part among the electrode parts of the chip part corresponds to the electrode part of the mounting object. Are pressed at a predetermined pressure, and both of these specific electrode parts are firmly joined to each other according to the law of metal-to-metal bonding so that the chip part is integrated with the mounting object. Pressurization can be performed without hindrance.

  In the invention of claim 6, the bonding method of parts according to the present invention can be faithfully realized, and the effect of the bonding method can be obtained with certainty.

  The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a schematic configuration of a component bonding apparatus that embodies a component bonding method according to an embodiment of the present invention. In this figure, this bonding apparatus includes a bonding head 3 that holds a bumpless chip component 2 such as an IC that has only been separated from a wafer through a scribing process inside a vacuum chamber 1 that is in a vacuum atmosphere, and a chip. The movable holding base 7 that holds and positions the circuit board 4 that is the mounting target of the component 2, and the chip component 2 and the circuit board 4 that are arranged opposite to the set position shown in the drawing are respectively viewed from the side in the horizontal direction. Most of the main components such as the first imaging means 8 for photographing and the second imaging means 9 for simultaneously photographing the positioning marks described later attached to each of the chip component 2 and the circuit board 4 facing each other at the setting position. Everything is installed.

  The bonding head 3 includes a component chucking mechanism unit 10 that detachably holds the chip component 2 and a rotation pressing unit 11 that includes a cylindrical roller that rotates while pressing the chip component 2 against the circuit board 4. It is rotatably mounted in a suspended form on the elevating body 13 via the connecting block body 12. The bonding head 3 is rotated via the connecting block body 12 by driving a head rotating servo motor 14 installed in the elevating body 13. The elevating body 13 is moved up and down along the guide rail 18 by driving the load control servomotor 17. The weight control servomotor 17 pressurizes the rotary pressing portion 11 of the bonding head 3 through the elevating body 13 with a predetermined pressure set in advance.

  The connecting block body 12 incorporates a component flatness adjusting mechanism 19, and this component flatness adjusting mechanism 19 adjusts the flatness of the bonding head 3 and thus the chip component 2 held by the bonding head 3. The flatness referred to here is horizontalness in this embodiment. Therefore, the component flatness adjusting mechanism 19 adjusts the inclination angle of the bonding head 3 so that the chip component 2 has a substantially accurate horizontal posture. To be adjusted. As this component flatness adjusting mechanism 19, an existing one having a well-known configuration is used. For example, the part to be adjusted is supported through a spherical sliding part and a plurality of piezoelectric elements are selectively energized. Thus, a configuration is provided in which the inclination of the bonding head 3 is adjusted so that the chip component 2 is positioned in an accurate horizontal state via the adjusted portion.

  On the other hand, an XY stage 21 is provided on a base 22 below the bonding head 3 inside the vacuum chamber 1, and the XY stage 21 advances and retreats in the X and Y directions perpendicular to each other on a horizontal plane. It can move freely. The movable holding table 7 is installed on the XY stage 21. Therefore, the movable holding table 7 holds the circuit board 4 at a predetermined position by the substrate chucking mechanism unit 20 provided therein. The stage 21 is moved in the X direction and the Y direction by the operation of the stage 21, whereby the position of the circuit board 4 on the movable holding base 7 is adjusted so as to be a predetermined relative position with respect to the upper chip component 2. Is done.

  Further, the movable holding table 7 is rotated by driving a holding table rotating servo motor 23 attached to the XY stage 21 and moving integrally, whereby the circuit board 4 is rotated by the movable holding table 7. It is designed to be rotated through. Further, the substrate holding degree 7 includes a substrate flatness adjusting mechanism 24, and the substrate flatness adjusting mechanism 24 is held on the upper surface of the moving holding table 7 by the substrate chucking mechanism 20. The flatness of the circuit board 4 has the same configuration as that of the above-described chip component flatness adjusting mechanism 19, and the circuit board 4 is adjusted to have an accurate horizontal posture. Therefore, in this embodiment, the chip component 2 and the circuit board 4 are adjusted to be in a horizontal arrangement by the chip component flatness adjusting mechanism 19 and the substrate flatness adjusting mechanism 24, thereby being accurately parallel to each other. The arrangement is corrected.

  This bonding apparatus is controlled by the controller 27 as a whole. That is, the controller 27 includes the component chucking mechanism unit 10, the head rotating servo motor 14, the load control servo motor 17, the substrate chucking mechanism unit 20, the XY stage 21, the holding table rotating servo motor 23, and the first. The imaging unit 8 and the second imaging unit 9 are controlled, and the component flatness adjusting mechanism 19 and the substrate flatness adjusting mechanism 24 are controlled based on the correction amount based on the calculation result performed by the image processing unit 28 described later.

  Prior to bonding the chip component 2 to the circuit board 4, the controller 27 performs control to position the chip component 2 held on the bonding head 3 at a setting position facing the circuit board 4 at a predetermined interval. The first imaging means 8 is installed at a position where the component imaging unit 8a and the board imaging unit 8b provided in the first imaging unit 8 can photograph the chip component 2 at the setting position and the circuit board 4 on the movable holding base 7 from the side surfaces. . Each of the component imaging unit 8a and the board imaging unit 8b includes a CCD camera and an optical lens system. Image data photographed by the first imaging means 8 is input to the image processing unit 28 and subjected to image processing.

  The second image pickup means 9 is provided so as to be movable in the horizontal direction at a position opposite to the first image pickup means 8, and is driven by an operating mechanism (not shown) to provide the chip component 2 and the circuit at the setting position. It is reciprocated between an imaging position between the boards 4 (shown by a solid line) and a retreat position (shown by a two-dot chain line) spaced laterally from the chip component 2 and the circuit board 4. The second imaging means 9 includes a component imaging unit 9a and a substrate imaging unit 9b for simultaneously imaging a positioning mark attached to a bonding surface (described later) of each of the chip component 2 and the circuit board 4 at the imaging position. doing. Each of the component photographing unit 9a and the board photographing unit 9b includes a CCD camera and an optical lens system. The image data photographed by the second imaging means 9 is also sent to the image processing unit 28 for image processing.

  FIG. 4A is a perspective view showing the bumpless chip component 2 and the circuit board 4 to be bonded by the bonding apparatus. The bumpless chip component 2 is an IC that is separated from a wafer through a scribing process and formed into a chip shape, unlike a conventional general IC in which bumps are formed. 4, a required number of copper electrode portions 2b are formed in a predetermined pattern with high density, and a plurality of positioning marks 2c are respectively attached to predetermined positions. On the other hand, on the circuit board 4, electrode portions 4 b corresponding to the respective electrode portions 2 b of the chip component 2 are formed on the bonding surface 4 a for the chip component 2 and correspond to the positioning marks 2 c of the chip component 2. Positioning marks 4c are formed at the locations.

  When bonding the chip component 2 onto the circuit board 4, the chip component 2 is positioned at a relative position where each positioning mark 2 c of the chip component 2 exactly matches each positioning mark 4 c of the circuit board 4. As shown in FIG. 4 (b), bumps are interposed between the electrode parts 2b of the chip component 2 and the electrode parts 4b of the circuit board 4 by the law of metal-to-metal bonding. Each is directly interconnected. Note that the intermetallic bond law is a phenomenon in which the cleaned surfaces of two metals are strongly joined when brought into contact with each other by applying a certain pressure in a vacuum atmosphere or in an atmosphere that does not oxidize. However, in order to perform this mutual joining accurately and reliably, it is necessary to solve the following problems.

  That is, since the bumpless chip component 2 to be bonded by the bonding apparatus has a relatively large number of electrode portions 2b arranged at a high density, both the chip component 2 and the circuit board 4 are connected to each other. The positioning marks 2c and 4c need to be superposed after being brought into alignment with very high accuracy.

  However, the bumpless chip component 2 inevitably becomes thinner than the existing IC as the electrode portion 2b increases in density. The positioning mark 2c of the chip component 2 may be detected while the chip component 2 is in a deformed state, and the detected position is aligned with the detection position of the positioning mark 4c on the circuit board 4. When the relative position between the component 2 and the circuit board 4 is determined, a positional deviation occurs between the electrode portions 2b and 4b arranged at high density.

  Further, in the above bonding apparatus, each electrode portion 2b of the chip component 2 and each electrode portion 4b of the circuit board 4 are directly joined to each other without interposing a bump. Regardless of the presence of distortion, strain, undulation, etc., it is necessary to jointly connect all of the electrode portions 2b, 4b in close contact with no gap.

  On the other hand, in the above-described bonding apparatus, the controller 27 controls the entire apparatus so as to solve the above-described problems, whereby suitable bonding can be performed. Next, the bonding process by the bonding apparatus will be described based on the flowchart of FIG.

  First, in a state where the inside of the vacuum chamber 1 is in a vacuum atmosphere, the controller 27 has the circuit board 4 and the chip component 2 in which the bonding surfaces 2a and 4a have been cleaned in advance facing each other at a predetermined interval in FIG. Whether or not it is set to the illustrated state is always determined based on whether or not a detection signal is input from a sensor (not shown) (step S1), and when it is determined that the setting is set, the head rotating servo motor 14 and the holding base are determined. A rotation command signal is given to the rotation servomotor 23, and the first imaging means 8 is commanded to shoot from the side of each of the chip component 2 and the circuit board 4 by the component imaging unit 8a and the board imaging unit 8b ( Step S2). As a result, the chip component 2 is rotated while being held by the bonding head 3 and the circuit board 4 is rotated while being fixed on the movable holding base 7, and the rotating chip component 2 and circuit board are rotated. 4 is imaged from the sides by the component imaging unit 8a and the board imaging unit 8b of the first imaging unit 8 respectively.

  For the above photographing, the chip component 2 and the circuit board 4 rotated at a constant low speed at a predetermined low speed are imaged by the component imaging unit 8a and the substrate imaging unit 8b at a constant time interval, and the chip component 2 at every predetermined angle. Any one of the method of temporarily stopping the rotation of the circuit board 4 and photographing with the chip component imaging unit 8a and the board imaging unit 8b at the timing when the rotation is stopped is employed. In any case, a plurality of locations on the side peripheral surfaces of the chip component 2 and the circuit board 4 are photographed. For example, when the chip component 2 is a general IC having a rectangular shape in plan view, the side surfaces of at least four sides of the chip component 2 are photographed. In this bonding apparatus, each of the chip component 2 and the circuit board 4 is photographed while rotating the chip component 2 and the circuit board 4 respectively, although only the single first imaging means 8 is used. Multiple locations on the side surface can be photographed.

  Image data captured by the component imaging unit 8 a and the board imaging unit 8 b of the first imaging unit 8 are input to the image processing unit 28. In response to a command from the controller 27, the image processing unit 28 performs image processing on the input image data to calculate the flatness of each of the chip component 2 and the circuit board 4 (step S3). Specifically, the image processing unit 28 compares and contrasts a plurality of image data obtained by photographing the chip component 2 and the circuit board 4 and recognizes the posture of each of the chip component 2 and the circuit board 4. 2 and the circuit board 4 are quadrangular in plan view, the tilt angle and tilt direction with respect to the horizontal plane are calculated by calculation based on the height difference of these four sides.

  Further, the image processing unit 28 performs an operation for calculating a flatness correction amount for operating the component flatness adjusting mechanism 19 and the board flatness adjusting mechanism 24 based on the flatness information calculated as described above. (Step S4). More specifically, the flatness correction amount is a correction amount necessary for correcting the chip component 2 and the circuit board 4 to the horizontal posture, respectively, in the X axis direction and the Y axis direction orthogonal to each other on the horizontal plane. It is a correction angle and a rotation direction for correcting the inclination.

  When the controller 27 receives the flatness correction amount from the image processing unit 28, the controller 27 controls the operation of the component flatness adjustment mechanism 19 and the board flatness adjustment mechanism 24 based on the flatness correction amount (step S5). . As a result, the chip component 2 and the circuit board 4 face each other in parallel with each other at a predetermined interval since the bonding surfaces 2a and 4a are both corrected in posture to a level within an allowable range.

  Subsequently, the controller 27 moves the second imaging means 9 from the retracted position indicated by the two-dot chain line in FIG. 1 to the imaging position indicated by the solid line, and then drives the second imaging means 9 to drive the component imaging unit 9a and The board imaging unit 9b causes each of the positioning marks 2c and 4c of the chip component 2 and the circuit board 4 to be photographed (step S6). The image data captured by the second imaging unit 9 is sent to the image processing unit 28.

  After receiving image data from the second imaging means 9 and receiving a command from the controller 27, the image processing unit 28 performs image processing on the input image data and positions each of the chip component 2 and the circuit board 4. An operation for calculating the relative displacement between the marks 2c and 4c is performed (step S7). Since the image data at this time was taken with both the chip component and the circuit board 4 corrected with the bonding surfaces 2a and 4a having a parallelism within an allowable range, the parallel relative as in the conventional case. Unlike the case of using image data obtained by imaging a positioning mark without correcting the position, the relative positional deviation amount calculated by the image processing unit 28 is extremely accurate.

  If the relative displacement amount is calculated by the image processing unit 28, the controller 27 adjusts the position of the circuit board 4 by controlling the operation of the XY stage 21 based on the calculated relative displacement amount, and rotates the head. One of the servo motor 14 for holding and the servo motor 23 for rotating the holding base is rotationally controlled to adjust the angle of either the chip component 2 or the circuit board 4 on the horizontal plane (step S8). That is, the controller 27 adjusts the position of the circuit board 4 and / or the chip component 2 so that the positioning marks 2c and 4c of the chip component 2 and the circuit board 4 are matched. As described above, this position adjustment is performed such that the extremely accurate relative displacement amount becomes zero. Therefore, after the position adjustment, the electrode parts 2b and 4b of the chip component 2 and the circuit board 4 are respectively accurate. Are positioned with high accuracy in the arrangement opposite to each other.

  If the relative position between the chip component 2 and the circuit board 4 is thus positioned with high accuracy, the controller 27 moves the second imaging means 9 to the retracted position indicated by the two-dot chain line in FIG. In addition, by giving a rotation command to the weight control servomotor 17, the bonding head 3 is lowered via the elevating body 13 and the chip component 2 held by the bonding head 3 is superposed on the circuit board 4 (step). S9). At this time, since the relative positions of the chip component 2 and the circuit board 4 are positioned with high accuracy, all the electrode portions 2b of the chip component 2 are accurately in contact with the corresponding electrode portions 4b of the circuit board 4. To do.

  Here, since the weight control servomotor 17 always applies a predetermined pressure set in advance to the rotary pressing portion 11, the chip component 2 is overlaid on the circuit board 4 when the chip component 2 is overlaid on the circuit board 4. The specific electrode portion 2b facing at least the rotation pressing portion 11 of each of the two electrode portions 2b is pressed against the corresponding electrode portion 4b of the circuit board 4 with a predetermined pressure, and is firmly established by the above-described law of intermetallic bonding. Interconnected. However, the bumpless chip component 2 to be bonded in this embodiment has deformation, distortion, distortion and waviness because the electrode portions 2b are thinly arranged with high density. There is a possibility that the other electrode parts 2 b except the specific electrode part 2 b in the chip component 2 may not be joined to the corresponding electrode parts 4 b of the circuit board 4.

  Therefore, as shown by a solid line in FIG. 3, the controller 27 gives a command to operate in the opening direction to the component chucking mechanism 10 of the bonding head 3 to release the holding of the chip component 2 (step S10). Thereafter, the operation of the XY stage 21 is controlled, and the circuit board 4 is predetermined in a direction (left and right direction in the figure) perpendicular to the axis of the rotary pressing portion 11 made of a cylindrical roller, as indicated by an arrow in FIG. Move within the range (step S11). The predetermined range is a range in which the rotary pressing portion 11 moves over the entire surface of the chip component 2.

  At this time, in the chip component 2, the specific electrode portion 2 b is firmly joined to the corresponding electrode portion 4 b of the circuit board 4 and integrated with the circuit board 4. It is moved together with the circuit board 4. Since the rotation pressing unit 11 is pressurized from the servo motor 17 for weight control so as to always have a predetermined pressure, the chip component 2 is rotated against the circuit board 4 at the predetermined pressure while rotating as the chip component 2 moves. Press. As a result, even if the chip component 2 is deformed, distorted, distorted, or undulated, all the electrode portions 2b of the chip component 2 are metal-to-metal bonded to the corresponding electrode portions 4b of the circuit board 4. Are firmly joined to each other by the law of

  As described above, in the bonding method, the chip component 2 and the circuit board 4 in the separated state are corrected by calculation from the results of image processing of a relatively large amount of image data obtained by imaging a plurality of locations on the side peripheral surfaces. In a state where the postures are corrected so as to be parallel to each other based on the amount, the positions of the positioning marks 2c and 4c of the chip component 2 and the circuit board 4 are detected to calculate the relative positional deviation amount. Since the chip component 2 and the circuit board 4 are aligned based on the relative displacement amount, the chip component 2 and the circuit board 4 can be positioned at an extremely high relative position of the order of 0.1 μm. After the chip component 2 is superposed on the circuit board 4 in the positioned state, the entire surface of the chip component 2 is pressed against the circuit board 4 with a predetermined pressure by the rotary pressing portion 11 and deformed into the chip component 2. Even if there is distortion, distortion, undulation, etc., all of the multiple electrode parts 2b arranged at high density in the chip component 2 are securely adhered to the corresponding electrode parts 4b of the circuit board 4 without any gaps. Can be joined together. Therefore, the chip component 2 is bonded to the circuit board 4 with high bonding strength, and the conductive resistance between the electrode portions 2b and 4b of both the chip component 2 and the circuit board 4 is extremely low.

  When the bonding of the chip component 2 to the circuit board 4 is completed in this way, the controller 27 controls the operation of the load control servomotor 17 to raise the bonding head 3 to the setting position shown in FIG. After S12), it is determined whether or not the bonding process is completed (Step S13), and the process returns to Step S1 and the same control process as described above is repeated until it is determined that the bonding process is completed. However, when bonding a plurality of chip components 2 to the same circuit board 4, the correction of the flatness of the circuit board 4 is omitted when bonding the second and subsequent chip components 2.

  In the above embodiment, the case where the chip component 2 is bonded to the circuit board 4 in the vacuum atmosphere of the vacuum chamber 1 by the law of intermetallic bonding has been described as an example. Alternatively, the chip component 2 may be bonded to the circuit board 4 according to the law of intermetallic bonding in an atmosphere of an inert gas such as argon gas. In the above embodiment, the case where both the chip component 2 and the circuit board 4 are arranged in parallel with extremely high precision so as to correct the flatness of both the chip component 2 and the circuit board 4 has been described. Even if the electrode portions 4b are arranged at a high density, there is less risk of deformation, distortion, distortion, undulation, etc., so just correcting the flatness of the chip component 2 as described above. Good.

  Further, in the above embodiment, the circuit board 4 is moved in the horizontal direction by the operation of the XY stage 21 so as to position the relative position between the chip component 2 and the circuit board 4. The component 2 may be moved in the horizontal direction. Further, the rotary pressing unit 11 is not limited to the cylindrical roller of the above embodiment, and a spherical body may be used as long as it can press the chip component 2 against the circuit board 4 while rotating.

  The relative position between the chip component and the mounting object can be positioned with extremely high accuracy, and all the electrodes of this chip component can be used even if the chip component is thin with the electrode portions arranged at high density. Can be bonded to the corresponding electrode part of the mounting object without any gaps, so that it is separated from the wafer through a next-generation mounting method that is expected to be implemented in the near future, for example, a scribe process. It can be suitably used for a mounting method in which a bumpless chip component such as a simple IC is directly bonded to a mounting object such as a circuit board.

1 is a longitudinal sectional view showing a schematic configuration of a chip component bonding apparatus that embodies a chip component bonding method according to an embodiment of the present invention; The flowchart which showed the control processing by the controller of a bonding apparatus same as the above. The enlarged view for demonstrating operation | movement of the bonding head in the bonding apparatus same as the above. (A) is a perspective view which shows the bumpless chip component and circuit board which are the object of bonding by the bonding apparatus same as the above, (b) is a side view of the state which bonded the bumpless chip component to the circuit board.

Explanation of symbols

2 Bumpless chip parts (chip parts)
2b Chip part electrode part 2c Chip part positioning mark 3 Bonding head 4 Circuit board (mounting object)
4b Electrode part of mounting object 4c Mark for positioning of mounting object 7 Movable holding base (holding base)
8 First imaging means (imaging means)
9 Second imaging means (imaging means)
10 Parts chucking mechanism (holding mechanism)
11 Rotation pressing unit 14 Servo motor for head rotation (component rotation drive source)
17 Servo motor for weight control (pressurization control drive source)
19 Component flatness adjusting mechanism 21 XY stage (moving mechanism)
27 Controller (control means)
28 Image processing unit

Claims (6)

A component bonding method for directly bonding each electrode part of a chip component to each corresponding electrode part of a mounting object,
The chip based on the flatness correction amount calculated from the result of image processing of image data obtained by photographing a plurality of locations on the side peripheral surface of the chip component from the side in a state where the chip component and the mounting object are separated from each other. A first step of correcting the component to a posture facing the mounting object in parallel;
A predetermined relative position based on a relative displacement correction amount calculated from an image processing result of image data obtained by photographing the positioning mark attached to each of the chip component and the mounting target that are opposite to each other in parallel. A second step of positioning to
The chip component positioned at a predetermined relative position and the mounting object are superposed on each other in a vacuum atmosphere or in an atmosphere that does not oxidize and pressurize, whereby each electrode of the chip component and the mounting object is provided. A third step of joining the parts;
A method for bonding parts, comprising:   In the first step, while rotating the bonding head that holds the chip component, the side peripheral surface of the chip component is imaged by a single imaging unit, and the chip is determined based on the height difference of the chip component in the image data obtained by the imaging. 2. The component bonding method according to claim 1, wherein an inclination amount and an inclination direction of the component are calculated as a flatness correction amount, and the posture of the chip component is corrected based on the calculated flatness correction amount.   In the first step, in addition to correcting the posture of the chip part based on the flatness correction amount, the side peripheral surface of the mounting object is made to be a single surface while rotating the movable holding table that holds the mounting object. An image is taken by an imaging means, and the inclination amount and the inclination direction of the attachment object are calculated as a flatness correction amount from the difference in height of the attachment object in a plurality of image data obtained by the imaging, and based on the calculated flatness correction amount The component bonding method according to claim 2, wherein the mounting object is corrected to a posture facing the chip component in parallel.   In the third step, after the chip component is polymerized to the mounting object by the operation of the bonding head that holds the chip component, the chip component held by the bonding head is released, and the chip component in the polymerized state and The rotation pressing portion that is provided on the mounting object and is rotated on the surface of the chip component by relatively moving a rotation pressing portion that is provided on the bonding and presses the chip component against the mounting object with a predetermined pressure. 4. The component bonding method according to claim 1, wherein the chip component is pressed against the mounting object with the predetermined pressure over the entire surface thereof.   In the third step, when the chip component is superposed on the mounting object by the operation of the bonding head, at least one electrode portion of the chip component is moved to the corresponding electrode of the mounting object by the rotation pressing portion of the bonding head. The component bonding method according to claim 4, wherein the parts are pressed against each other with a predetermined pressure so as to be bonded to each other according to the law of bonding between metals. A bonding head provided with a holding mechanism for detachably holding the chip component and a rotation pressing portion that presses the chip component against an object to be mounted with a predetermined pressure, and is rotatable and can be moved up and down;
A component rotation drive source for rotating the bonding head;
A pressurization control drive source that pressurizes the rotary pressing unit at a predetermined pressure;
A component flatness adjusting mechanism capable of freely adjusting an inclination angle with respect to a horizontal plane with respect to the holding mechanism;
A holding table for holding the mounting object in an arrangement opposite to the chip component;
A moving mechanism for moving at least one of the bonding head or the holding table in a horizontal direction;
First imaging means for photographing a side peripheral surface of the chip component rotated by driving of the component rotation driving source while being held by the bonding head from the side;
Second imaging means for imaging each of the chip parts facing each other in the separated state and the positioning marks attached to the mounting object;
An image processing unit that performs image processing on image data captured by each of the first and second imaging units to calculate a flatness correction amount of the chip component and a relative positional deviation correction amount between the chip component and the mounting target; ,
Based on the flatness correction amount and the relative positional deviation amount correction calculated by the image processing unit, the component flatness adjusting mechanism and the moving mechanism are respectively controlled to operate so that the chip component is parallel to the mounting object. After the correction, the chip component and the mounting object are positioned at a predetermined relative position, the chip component is superposed on the mounting object, and the moving mechanism is operated to activate the chip part in a superposed state. And a control means for controlling the mounting object and the rotation pressing portion to move relative to each other;
A bonding apparatus for parts, comprising:

Images