KR20060051227A - Bonding apparatus - Google Patents

Abstract

Bonding apparatus WHEREIN: It makes position shift in bonding less.

ΔX in positioning when the first camera 26 shifts + Xc with respect to the second camera 28 and the bonding tool 12 deviates by + Xn when the bonding tool 12 moves from the height Z ₁ to the height Z ₂ . It is enough to correct = (Xn-Xc). In the calibration position of the bonding device to install the target 32 to the substrate height (Z _1), and installing the correction camera 30 in the downward direction. First position deviation X ₁ , which is the position of the target 32 as viewed from the camera 30 for correction, Second position deviation X ₂ , which is the position of the target 32 as viewed from the second camera 28, and the first camera the location of chip (10u) in the height (Z ₂₎ from 26 3 position deviations (X _3), location of the chip (10d) in the height (Z ₁₎ from the calibration camera 30 Based on the fourth position deviation X ₄ , the correction amount ΔX can be obtained.

Bonding apparatus, bonding tool, measuring member, camera, substrate, bonding working surface, target, imaging data, imaging reference position, calculating means, measuring means

Description

Bonding Device {BONDING APPARATUS}

1 is a diagram illustrating the principle of the present invention.

It is a block diagram of the bonding apparatus in embodiment which concerns on this invention.

3 is a diagram illustrating an internal configuration of a vertical camera.

4 is a plan view of the target.

It is a figure which shows typically the planar arrangement of the bonding apparatus in embodiment which concerns on this invention.

It is a figure which shows typically the side arrangement of the bonding apparatus in embodiment which concerns on this invention.

FIG. 7 is a side arrangement diagram when a third position deviation is obtained from the first position deviation in the embodiment according to the present invention. FIG.

FIG. 8 is a diagram showing a state of the captured image data when the first positional deviation is obtained in the embodiment according to the present invention. FIG.

FIG. 9 is a diagram showing the shape of captured image data when the second positional deviation is obtained in the embodiment according to the present invention. FIG.

It is a figure which shows the shape of the imaging data at the time of obtaining the 3rd positional deviation in embodiment which concerns on this invention.

Fig. 11 is a side elevation view when the fourth positional deviation is obtained in the embodiment according to the present invention.

It is a figure which shows the shape of the imaging data at the time of obtaining 4th positional deviation in embodiment which concerns on this invention.

It is a figure which shows the shape of the imaging data at the time of positioning by performing correction amount (DELTA) (X, Y) in embodiment which concerns on this invention.

FIG. 14 is a diagram illustrating a method of positioning a chip and a substrate when the optical axes of the two cameras do not deviate. FIG.

FIG. 15 is a diagram illustrating a method of positioning a chip and a substrate when the optical axes of two cameras deviate. FIG.

16 is a diagram illustrating a method of positioning a chip and a substrate when the optical axes of the two cameras do not deviate but a shift due to the movement of the bonding tool occurs.

(Explanation of the sign)

10, 10u, 10d chip 12, 12u, 12d bonding tool

14 boards 16 carriers

20,60 vertical camera 22, 24, 31 optical axis

26 First Camera 28 Second Camera

30 Calibration camera 32, 33 target

50 bonding devices 52 supply stations

54 Target Shifter 62,64 Reflector

66 Duplex Reflector 90 Pickup Position

92 Positioning and Bonding Position 94 Correction Position

96 evacuation position 100 control unit

102 CPU 104 Input

106 Output 108 Memory

110 Bonding tool control unit 112 Camera control unit for correction

114 Target control unit 116 Up and down camera control unit

120 Position shifter 122 Positioner

124 Bonding Process 130 First Position Deviation Measuring Module

132 2nd position deviation measuring module 134 3rd position deviation measuring module

136 4th position deviation measuring module 138 Position shift calculation module

150, 156, 162 Imaging Data 152, 158, 164 Cross Pattern 154, 160 Target Pattern 166u, 168d Reference Pattern

TECHNICAL FIELD This invention relates to a bonding apparatus. Specifically, It is related with the bonding apparatus which has the positioning mechanism of the position of a bonding tool, and the position of a board | substrate.

As a mounting method for connecting a bonding pad of a chip such as an LSI and a bonding lead of a substrate, face down bonding is performed in addition to wire bonding. The face down bonding holds the back side of the chip in the bonding tool, and faces the surface side of the held chip, that is, the side on which the electrode pad is arranged, and the wiring surface of the substrate, and the position of the electrode pad of the chip and the substrate. Is a method of positioning the bonding lead and connecting using thermal energy or ultrasonic energy. As the face down bonding apparatus, flip chip bonding, C0F (Chip 0n Film) bonding, or the like can be used.

In the face down bonding, it is necessary to observe the electrode pads on the surface of the chip and the bonding leads on the surface of the substrate facing each other. Therefore, a camera for positioning the chip and a camera for positioning the substrate can be used. Can be. For example, when mounting a chip by lowering a bonding tool from the upper side of a board | substrate, as a board | substrate position measuring camera, the downward camera which observes the upper side from the top is used, and the chip position measuring camera which observes the upper side from the lower side. Use an upward camera.

One of the arrangement methods regarding two cameras can provide a downward camera above a height position of a board | substrate, and can separate an upward camera below a height position of a board | substrate separately from this. In addition, Patent Document 1 discloses an optical device that can simultaneously observe a chip surface and a substrate surface by using a prism mirror having two reflective surfaces, dividing the light beams into upper and lower portions of the prism mirror. In this case, the optical device is inserted between the chip and the substrate so that the chip and the substrate can be simultaneously observed. Such a camera is called a probe camera.

In either case, in the above example, the optical axis for observing the chip is upward, and the optical axis for observing the substrate is downward, and is a separate optical axis. Therefore, when these optical axes deviate, it affects positioning and in bonding. This may cause misalignment of the. The deviation of the optical axis is caused by, for example, the setting of the optical system or the like being shifted due to the influence of a temperature rise or the like in the bonding operation or a change with time. The following describes how the deviation of the optical axis affects the positional deviation in bonding.

First, a method of positioning a general chip and a substrate when the optical axis is not deviating is shown in FIG. For simplicity of explanation, only the positioning in the X direction shown in the figure is considered. The chip 10 is held in the bonding tool 12 and the substrate 14 is held in the carrier 16. The bonding tool 12 and the carrier 16 are each movable to an arbitrary position in the X direction by a driving device not shown. The up-and-down camera 20 which observes the chip 10 and the board | substrate 14 is arrange | positioned between the chip | tip 10 and the board | substrate 14, by the 1st camera 26 which has an upward optical axis 22. The position of the chip | tip 10 can measure the position of the board | substrate 14 with the 2nd camera 28 which has the optical axis 24 of the downward direction. In addition, although it is necessary to consider the magnification of each camera at the time of measuring a position or the distance between positions, in the following, unless otherwise indicated, the distance between the positions measured by a camera is an actual distance, ie, on an object plane. The explanation will be made in terms of distance.

14 is a case where the upward optical axis 22 and the downward optical axis 24 are exactly aligned. In this case, since the center of the field of view of the first camera 26 and the center of the field of view of the second camera 28 coincide with each other, the reference position of the chip 10 and the reference position of the substrate 14 are respectively positioned at the positions. That's right. As a reference position for bonding, the edge position of the electrode pad of the chip 10, the edge position of the bonding lead of the board | substrate 14 corresponding to it, etc. can be selected. In FIG. 14, for example, the upward optical axis 22 indicates the center position of the visual field of the first camera 26, and the downward optical axis 24 indicates the center of the visual field of the second camera 28. do. When the position of the chip | tip 10 and the board | substrate 14 was measured in that state, it shifted as shown by the broken line of FIG. In this case, the carrier 16 is first moved until the reference position of the substrate 14 coincides with the downward optical axis 24 representing the center of the field of view of the second camera 28. The bonding tool 12 is moved until the reference position of the chip 10 coincides with the upward optical axis 22 representing the center of the field of view of the first camera 26. In this way, the chip | tip 10 and the board | substrate 14 are positioned, and if there is no other cause, the position shift in bonding will not occur.

If for some reason, the upward optical axis 22 representing the center of the visual field of the first camera 26 and the upward optical axis 24 representing the center of the visual field of the second camera 28 are shifted, the method of FIG. Insufficient That is, the reference position of the substrate 14 coincides with the downward optical axis 24 representing the center of the field of view of the second camera 28, and further, the reference position of the chip 10 is the field of view of the first camera 26. Even if coincident with the upward optical axis 22 representing the center of the chip 10, the chip 10 is not bonded to the desired substrate 14 position. 15 shows a downward optical axis 24 showing the center of the field of view of the second camera 28 as a reference position of the substrate 14 with respect to the case where the optical axis 22 deviates from + Xc with respect to the optical axis 24. It is a figure which shows the state matched to. Even if the chip 10 is in the position of the broken line, even if it coincides with the upward optical axis 22 representing the center of the field of view of the first camera 26, the optical axis 22 is + relative to the optical axis 24. Since Xc is peeled off, the reference position of the chip 10 fitted thereto is shifted by + Xc with respect to the reference position of the substrate 14.

Therefore, in order to bond to the correct position without causing a misalignment in the bonding, the first camera 26 based on the optical axis 24 representing the center of the field of view of the second camera 28 in some way is used. It is necessary to measure the shifted amount (+ Xc) of the optical axis 22 representing the center of the field of view. Based on the measured shift amount (+ Xc), the optical axis shifts between the two cameras by adjusting the reference position of the chip 10 to a position where only -Xc is corrected based on the center of the field of view of the first camera 26. Even in this case, accurate bonding can be performed.

As a measuring method of the shift | offset | difference amount of a 1st camera and a 2nd camera, patent document 2 arrange | positions a reference mark on two surfaces or reference surfaces from which height differs, respectively, beforehand between two other reference marks of this height Disclosed is a method of adjusting and aligning the positional relationship of and aligning the positional relationship. That is, an optical device capable of observing the chip surface and the substrate surface at the same time is inserted between two reference marks in which the positional relationship is arranged in advance, and the amount of deviation between the first camera and the second camera is measured.

In addition, Patent Literature 3 discloses a semiconductor positioning device having a first recognition camera and a second recognition camera having directions in which optical axes face each other, wherein the height of the first recognition camera and the height of the second recognition camera are provided. A method of detecting a change in a reference position in two recognition cameras as a target is disclosed. That is, the first recognition camera and the second recognition camera are moved relatively so that the first recognition camera and the second recognition camera can be coaxially positioned, and the reference positions of the first recognition camera and the second recognition camera are measured and stored with respect to the target. Then, the normal bonding operation is performed, and then the same measurement as the previous reference position measurement is performed again, and the change of the reference position in the two recognition cameras is checked by checking whether the measured position is changed from the stored reference position. Can be detected.

(Patent Document 1) Japanese Unexamined Patent Application Publication No. 2001-176934

(Patent Document 2) Japanese Unexamined Patent Publication No. 6-28272

(Patent Document 3) Japanese Patent No. 2780000

As the trend of multipinning and miniaturization of chips and substrates has advanced, it has been required for face down bonding devices to place chips more precisely on substrates. In order to more accurately arrange the chip on the substrate, it is necessary to reduce the positional shift in the bonding. Thus, as described above, it is necessary to more accurately detect the deviation between the two cameras.

In the prior art method of detecting the deviation between two cameras, the method of Patent Document 2 requires two targets, and further requires adjustment and alignment of the positional relationship between these targets, and the configuration is complicated, so that the work takes time. It costs.

Moreover, in the method of patent document 3, the focusing position of a recognition camera is restrict | limited in order to perform an accurate shift detection. That is, in this method, when recognizing a target, the focusing position of the first recognition camera and the focusing position of the second recognition camera are also required to be on the target, and the camera which recognizes the chip in positioning at the time of bonding. The focusing position of is on the chip, and the focusing position of the camera that recognizes the substrate needs to be on the substrate.

In addition, although a reference position can be provided by using a target, the position of the target itself can be deviated by the influence of temperature rise, etc. in a bonding operation, or the change with time, and in some cases sufficient position It is not a standard.

In addition, in the bonding operation, when the bonding tool does not move parallel to the optical axis from the positioning height to the bonding height on the substrate, positional shift in bonding occurs. Based on this, for example, the amount of deviation (+ Xc) between the optical axis of the first camera and the optical axis of the second camera can be accurately measured, and even if the correction is performed, it may not be possible to accurately place the chip on the substrate. . The shape is shown in FIG.

In FIG. 16, the upward optical axis 22 and the downward optical axis 24 are accurately aligned. In this case, if the bonding tool 12 is moved in parallel with the optical axis 22 from the height on the substrate to the height of the focusing position of the first camera 26, the second camera 28 will be described with reference to FIG. 14. The reference position of the substrate 14 is aligned to the center of the field of view, and then the reference position of the chip 10 and the reference position of the substrate 14 are aligned to the center of the field of view of the first camera 26. Now, while the bonding tool 12 moves from the height on a board | substrate to the height of the focusing position of the 1st camera 26, the position is out of + Xn. At this time, the reference position of the substrate 14 coincides with the downward optical axis 24 representing the center of the field of view of the second camera 28, and the reference position of the chip 10 corresponds to the field of view of the first camera 26. Even if coincident with the upward optical axis 22 representing the center of the chip 10, the chip 10 is bonded at the position of -Xn on the substrate 14 instead of the desired position of the substrate 14, whereby the position shift in bonding is caused. Happens.

Therefore, in order to arrange the chip 10 at the correct position on the substrate 14, the first camera is based on the shifted amount of the bonding tool 12, that is, the position on the height of the substrate, in some way. It is necessary to measure the amount of deviation (+ Xn) between moving to the height of the focusing position of (26). When the amount of deviation (+ Xn) is measured, only the reference position of the chip 10 is corrected by reference to the center of the field of view of the first camera 26 so that the reference position of the chip 10 is not bonded to the position of -Xn on the substrate 14. By adjusting to one position, the position shift in bonding can be suppressed and the chip | tip 10 can be arrange | positioned in the exact position on the board | substrate 14.

In the method of patent document 1 and patent document 2, the shift | offset | difference amount by the movement of a bonding tool is unknown. However, in general, the amount of deviation (+ Xn) can be measured by performing test bonding. In other words, even if the shifted amount (+ Xn) is not known, the reference position of the substrate 14 is matched with the downward optical axis 24 representing the center of the field of view of the second camera 28, and further, the reference position of the chip 10. When bonding is performed by coinciding with the upward optical axis 22 representing the center of the field of view of the first camera 26, as described above, the chip 10 deviates by -Xn from the substrate 14. Therefore, if the sign of the shifted amount detected by the test bonding is reversed, the shifted amount (+ Xn) due to the movement of the bonding tool can be obtained.

However, what can be measured by test bonding is the amount of the shift between the external shape on the back side of the chip and the substrate, and the amount of the shift between the electrode pad of the chip and the bonding lead of the substrate cannot be accurately measured. In addition, in order to perform test bonding during the bonding operation, there is a possibility of waste of the substrate and the chip, and it is not efficient to carry out the test bonding offline.

Thus, in the prior art, in order to measure the amount of deviation between two cameras, there is a limitation in the configuration of the apparatus including the target used for the position reference, and the amount of deviation due to the movement of the bonding tool cannot be measured accurately. . Therefore, at the time of positioning of the chip and the substrate in bonding, it is difficult to correct these misaligned amounts more accurately, and the positional deviation in the bonding cannot be made smaller. In addition, it is not possible to detect an amount that is shifted with sufficient precision due to a change over time of the position of the target.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art and to provide a bonding apparatus which can reduce the positional shift in bonding. Another object is to provide a bonding apparatus capable of correcting a shifted amount of movement of a bonding tool together with a shifted amount between two cameras for positioning at the time of positioning a chip and a substrate in bonding. Another object is to provide a bonding apparatus capable of suppressing the influence of the change caused by the passage of time of the target position in correcting the shifted amount.

(Principle of the present invention)

In the following, the principle of the present invention which can reduce the positional shift in the bonding, in particular, in the positioning of the chip and the substrate in the bonding, the shift of the bonding tool together with the shifted amount between the two cameras for positioning Explain the principle of correcting misalignment. Here, as described with reference to Figs. 14 to 16, the positioning in the one-dimensional direction, that is, the X-direction is explained. However, it is easy to expand the two-dimensional positioning into a two-dimensional vector by changing the one-dimensional vector into a two-dimensional vector. Do. 14 to 16, it is necessary to consider the magnification of each camera when measuring the position or the distance between the positions, but the distance between the positions measured by the cameras is also defined below unless otherwise specified. The description will be made in terms of the actual distance, that is, the distance on the object plane.

Initially, in the case where there is a shift amount of the movement of the bonding tool together with the shift amount between the two cameras for positioning, in order to eliminate the shift in the bonding, the amount of correction to be corrected for the positioning of the chip and the substrate ( ΔX). Using the coordinate system and symbols as shown in Figs. 14 to 16 for the arrangement, the shifted amount and the correction amount of each element, as described above, the correction amount for the shifted amount (+ Xc) of the two cameras is -Xc. The correction amount for the shifted amount (+ Xn) due to the shift is + Xn. And when these two exist together, even if the shift | offset | difference by the movement of the + Xn bonding tool in FIG. 15 arises, even if the optical axis shift | offset of + Xc occurs in FIG. In this case, the correction amount to be corrected is (-Xc + Xn). Therefore, when there exists an amount of shift | offset | difference of the movement of a bonding tool with the amount of shift | offset between two cameras for positioning, the correction amount ((DELTA) X) for positioning required in order to eliminate the position shift in bonding is a following formula. Is given in (1).

ΔX = -Xc + Xn ... (1)

The bonding apparatus according to the present invention has a correction function for obtaining a correction amount ΔX for correcting the positional shift in bonding in addition to the function of positioning the chip held in the substrate and the bonding tool. In other words, unlike the positioning and bonding positions for positioning and bonding, a correction position for obtaining the correction amount ΔX is set. In the correction position, a target that is a position reference for correction, a correction camera is provided, a first camera for measuring the position of the chip, a second camera for measuring the position of the substrate, and a bonding tool for holding the chip in the correction position. It is movable.

1 is a diagram illustrating the positional relationship of each element in the correction position. Elements common to Figs. 14 to 16 are given the same reference numerals. In the coordinate system, the plane parallel to the bonding surface on which the bonding is made is referred to as the XY plane, and the X-axis and the Z-axis are represented by a direction in which the bonding tool 12 moves in the vertical direction as a Z direction perpendicular to the XY plane. The heights Z ₁ and Z _{2 in the} Z-axis direction are the heights of the substrates in the positioning and bonding positions and the heights of the chips held in the bonding tool, respectively. In addition, when performing positioning in the positioning and bonding position, the upper and lower cameras 20 move to the position, and the focusing position of the first camera 26 is on the surface of the chip held in the bonding tool, that is, Z _2. And the focusing position of the second camera 28 is set above the surface of the substrate, that is, at the height of Z ₁ .

As shown in FIG. 1, the correction camera 30 and the target 32 which are the positional standards for correction | amendment are arrange | positioned in the predetermined position with a correction position. The target 32 is provided at the position of the height Z ₁ , ie, at the same height as the bonding height of the substrate 14. The camera 30 for correction can observe the target 32, and is arrange | positioned upward from the target 32 below the target 32 as a focusing position.

In addition, in FIG. 1, although the target 32 uses the reference pin which has a longitudinal axis in a horizontal plane, ie, an XY plane, and makes the front end into the position reference for correction, the correction camera 30 is used as a position reference for correction. And the position reference can be picked up from both of the second cameras 28.

Next, the operation of each element for obtaining the correction amount [Delta] X and the positional relationship on the X axis at that time will be described. Initially, the bonding tool 12 is moved to a correction position by moving a predetermined distance from a positioning / bonding position (not shown), and is pulled upwards further.

The height of the chip 10u held in the bonding tool 12u at that time is taken as the height Z ₂ of the focusing position of the first camera 26. Further, the subscript u is, indicates that the height (Z _2), when in the height (Z ₁₎ which will be described later wihaeseoda to identify and attach a subscript d. In this state, the first camera 26 and the second camera 28 are moved a predetermined distance from a positioning / bonding position (not shown) as one set to be moved to the correction position, and the second camera 28 and the camera 30 for correction are as follows. ) Target 32 is imaged, and chip 10u at height Z ₂ held in bonding tool 12u by first camera 26 is imaged.

Next, in order to calculate the positional relationship of each element, as shown in FIG. In Fig. 1, the _{X 1, X 2, X 3} , X 4, Xc, Xn will be described below as a vector, there is shown that the forward direction of the arrow. Here, let the position of the optical axis 24 which shows the imaging center of the 2nd camera 28 be _Xb , and let this represent the positional relationship on the X-axis of each element with reference. If X ₂ is the distance from the position X _b of the optical axis 24 to the tip position of the target 32, the line unit value of the target 32 is X _b + X ₂ . X ₂ can be obtained from the imaging data of the second camera 28.

If X ₁ is the distance from the optical axis 31 indicating the imaging center of the correction camera 30 to the tip position of the target 32, the position of the optical axis 31 indicating the imaging center of the correction camera 30 will be described. Is X _b + X ₂ -X ₁ . The sign of X ₁ becomes negative because, in the example of FIG. 1, the positive direction of the vector X ₁ is the -X direction. X ₃ can be obtained from the imaging data of the camera 30 for correction.

Moreover, supposing Xc is the distance from the optical axis 24 which shows the imaging center of the 2nd camera 28 to the optical axis 22 which shows the imaging center of the 1st camera 26, imaging of the 1st camera 26 is carried out. the position of the optical axis 22 represents the center is a, X _b + X _c. Then, when the X ₃ as distance to the reference position of the chip (10u) in the height (Z ₂₎ from the optical axis 22 of the upstream showing an imaging center of the first camera 26 and a height (Z ₂₎ The reference position of the chip 10u in X is X _b + X _c + X ₃ . X ₃ can be obtained from the imaging data of the first camera 26.

Next, if necessary, the first camera 26, the second camera 28, and the target 32 are properly retracted, and then the bonding tool 12 is lowered to have a height equal to the height Z ₁ of the substrate 14. The height of the chip 10d held in the bonding tool 12d is taken. At this time, the position shift Xn occurs due to the movement in the Z-axis direction of the bonding tool 12, but in this state, the chip 10d held in the bonding tool 12d is imaged by the correction camera 30. Chip in the X ₄ in the calibration camera (30) when said distance to the reference position of the chip (10d) in the height (Z ₁₎ from the optical axis 31 represents the image pickup center, the height (Z ₁₎ of the ( The reference position of 10d) is X _b + X ₂ -X ₁ + X ₄ . X ₄ can be obtained from the imaging data of the camera 30 for correction.

Here, the height shifted position Xn by the movement of the bonding tool 12 was seen from the reference position X _b + X ₂ -X ₁ + X ₄ of the chip 10d at the height Z ₁ . Suppose the distance to the reference position of the chip 10u in (Z ₂ ), the reference position of the chip 10u in the height (Z ₂ ) is X _b + X ₂ -X ₁ + X ₄ + Xn to be.

Since the reference position of the chip 10u at the height Z ₂ obtained by the first camera 26 is X _b + X _c + X ₃ , this is X _b + X _2- X ₁ + X ₄ + Same as Xn,

X _b + X _c + X ₃ = X _b + X ₂ -X ₁ + X ₄ + Xn and, moreover, Xc = X ₂ -X ₁ + X ₄ + Xn-X ₃ Becomes

Here, when the correction amount ΔX = -Xc + Xn is introduced, equation (2) is obtained.

-Xc + Xn = △ X = X _3- (X ₂ -X ₁ + X ₄ ) ... (2)

Since X ₃ , X ₂ , X ₁ , and X ₄ , which are components on the right side of the formula (2), are positions shift amounts requested from the imaging data, respectively, the correction amount (ΔX) =-Xc + Xn is based on the respective imaging data. Can be obtained by Thus, according to the structure of this invention, although the amount of shift | deviation (+ Xc) of two cameras and the amount of shift | deviation (+ Xn) by the movement of a bonding tool are not measured independently, the required correction amount ( ΔX) can be obtained.

Further, X _3, X _2, X _1, X ₄ is, by using the reference position on the one reference position, and the bonding tool 12 can be calculated from the image data of each camera. Therefore, as in the prior art, there is no need to use two targets in which the alignment relationship is adjusted in advance, or there is no restriction on the focusing positions of the first camera and the second camera with respect to the target.

Moreover, by using the target 32 of the above-mentioned structure, in the correction of the shift | offset | difference amount, the influence of the change with the passage of time of a target position can be suppressed. That is, first, the measurement of the tip position of the target 32 is performed by the correction camera 30 and the second camera 28 in the correction position, but this is the line unit value of the same target 32 in the vertical direction. Image processing can be performed by imaging from the camera, so that the processing can be performed at substantially the same time. In addition, since the measurement of the target 32 is not necessary, the position of the target 32 does not change mostly between these two imaging processes, and accordingly, the influence of the change with the passage of time in the position of the target 32 is determined. Can be suppressed.

Secondly, when the imaging process of the tip position of the target 32 is completed, the tip position of the target 32 is obtained, and the calculated value is stored and used for the subsequent misalignment calculation. You may evacuate to a suitable position. That is, the target 32 can be retracted out of the place which is not affected by the temperature of the bonding operation, and the like can be prevented from affecting the reproduction accuracy of the tip position of the target 32.

In addition, in the measurement of X ₁ , even if the height position of the bonding tool is not set to the height position Z ₁ of the substrate 14, X ₃ , X ₂ , X ₁ , and X ₄ are obtained from the imaging data and the equation (2) is obtained. ) Can be calculated. As described above, when X ₃ , X ₂ , X ₁ , and X ₄ are obtained, there are no restrictions on the apparatus as in the prior art. Correction can be performed more accurately than in the prior art, and positional shift in bonding can be suppressed more.

However, when the height position of the bonding tool is not set to the height position Z ₁ of the substrate 14, there are not enough corrections due to the shift due to the vertical movement of the bonding tool, more preferably a test. Bonding is used together. For example, the positioning is corrected based on the correction amount requested in equation (2), and furthermore, test bonding is performed in the state where the correction is made, and the correction amount due to the shift caused by the vertical movement of the bonding tool after the correction. Obtain separately. By using test bonding together in this way, position shift in bonding can be further suppressed.

(Solution Solution)

The bonding apparatus according to the present invention is a bonding tool or a bonding object held in the bonding tool, or at least one of the measuring members held in the bonding tool as an object relating to the bonding tool, and measuring the position of the object in relation to the bonding tool. A positioning mechanism including a first camera and a second camera for measuring the position of the substrate, and positioning the bonding object held in the bonding tool by the positioning mechanism at a determined position of the substrate arranged on the bonding work surface for bonding. In the bonding apparatus for performing the positioning, the positioning mechanism further captures the target by a target having a position reference and observable from both sides, a camera for correction disposed in a predetermined positional relationship on one side of the target, and a camera for correction. First measuring means for obtaining a first position deviation between the position reference of the target and the imaging reference position of the camera for correction in the image pickup data; The second camera is placed on the other side of the target in the established positional relationship, the target is photographed by the second camera, and the second position deviation between the positional reference of the target and the imaging reference position of the second camera is obtained from the imaging data. The second measuring means and the first camera are opposed to the object related to the bonding tool in a predetermined positional relationship, and the first camera captures the object related to the bonding tool, and the reference position and the reference position of the object relating to the bonding tool in the imaging data. The third measuring means for obtaining the third positional deviation between the imaging reference positions of the first camera, and the object relating to the bonding tool on the other side of the target in a predetermined positional relationship, and the correction camera Fourth measurement means for imaging the object and obtaining a fourth positional deviation between the reference position of the object with respect to the bonding tool and the imaging reference position of the camera for correction in the image pickup data; Calculation means for calculating the positional shift in bonding based on the value deviation, the second positional deviation, the third positional deviation and the fourth positional deviation, and the positional shift in the bonding is corrected based on the calculation result. And imaging means of the target in the first measuring means and imaging of the target in the second measuring means are performed substantially simultaneously.

Moreover, the bonding apparatus which concerns on this invention WHEREIN: The memory | storage means which stores the imaging data of a target or the data based on it is equipped, and a target is withdrawn from an imaging position after the imaging data or the data based thereon is stored. It is desirable that it is possible.

In the bonding apparatus according to the present invention, it is preferable that the target moves in the height direction and retracts at a height that is out of the focusing position of the correction camera.

In addition, the target is preferably a reference pin having a longitudinal axis disposed in the horizontal plane.

Moreover, it is preferable that a target is arrange | positioned at the height substantially equal to the height in which a board | substrate is arrange | positioned.

Moreover, it is preferable that a 4th measuring means arrange | positions the object with respect to a bonding tool at the height substantially equal to the height where a board | substrate is arrange | positioned, and calculate | requires a 4th position deviation.

According to the above configuration, the positioning mechanism having the first camera and the second camera further includes a target having a positional reference and a correcting camera, in order to correct the positional misalignment. The first positional deviation between the reference position, the second positional deviation between the positional reference of the target and the imaging reference position of the second camera, and between the reference position of the object with respect to the bonding tool and the imaging reference position of the first camera And a fourth positional deviation between the reference position of the object with respect to the bonding tool and the imaging reference position of the camera for correction. Since the fourth position deviation from the first position deviation corresponds to X ₁ , X ₂ , X ₃ , X ₄ described in the principles of the present invention, the position shift in bonding is obtained based on these and corrected. Therefore, positional shift in bonding can be made smaller.

At this time, the target is picked up by the second camera and the correcting camera, but since the picking up is performed at substantially the same time, the position where the change over time of the target position during the correction operation is based on the picked-up data. Influence on the calculation of the deviation can be suppressed. For example, in the case where the bonding apparatus has a heater or the like, the position of the target may change even during the correction operation by the high environmental temperature. Regarding such a change over time, by performing all of the imaging required for the target at about the same time, the influence due to the difference in the acquisition time of the imaging data can be eliminated.

In addition, since the target is to be retracted from the imaging position after the imaging data and the like are stored, in order to obtain the fourth positional deviation, in spite of the disturbance of the setting of the height position of the object with respect to the bonding tool, for example, imaging of the target is performed. It is also possible to accurately set the height of the object with respect to the bonding tool at the height of the position. Furthermore, the target is sufficiently removed from the bonding tool to be retracted so that the influence of temperature, for example, when the bonding tool is at a high temperature, does not reach the target.

Furthermore, since the target moves in the height direction and retracts, the reproducibility of the position in the horizontal plane can be improved as compared with the target retracting in the horizontal direction. Moreover, since it retracts to the height which deviates from the focusing position of a correction camera, it does not affect the imaging data of a correction camera.

In addition, since the target is a reference pin having a longitudinal axis in the horizontal plane, the target can be easily produced as a position reference, and compared with the case where the target of the transparent plate is used, such as refraction when light passes through the transparent plate, etc. No influence

Moreover, a target is arrange | positioned at the height substantially equal to the height where a board | substrate is arrange | positioned. The object with respect to a bonding tool is arrange | positioned at the height which is substantially the same as the height where a board | substrate is arrange | positioned, and a 4th position deviation is calculated | required. Thereby, as described in the principle of the present invention, the amount of correction when the shift (+ Xn) due to the movement in the height direction of the bonding tool and the shift (+ Xc) between the two cameras for positioning are present together X = Xc + Xn is found and these are corrected. Therefore, positional shift in bonding can be made smaller.

(The best mode for carrying out the invention)

EMBODIMENT OF THE INVENTION Hereinafter, embodiment which concerns on this invention is described in detail using drawing. In addition, in the following description, the same code | symbol is attached | subjected to the element similar to FIGS. 14-16 and FIG. In the following description, the bonding apparatus is described as a COF (Chip On Film) bonding apparatus for face-down bonding an LSI chip having a bump to a film substrate, but the chip may be a semiconductor device or an electronic device other than the LSI chip, and the substrate is thin. You may use an epoxy board | substrate and the tape board | substrate which extended the bonding lead to the opening area | region of a film. Although a COF (Chip On Film) bonding apparatus heats a bonding tool and demonstrates that a bump and a board | substrate are bonded by the heat | fever, it may heat the board | substrate side elsewhere, and may heat both a bonding tool and a board | substrate. Moreover, the bonding apparatus which uses ultrasonic energy together and lowers a heating temperature may be sufficient.

2 is a configuration diagram of a bonding device 50 for COF. The bonding apparatus 50 supplies the bonding tool 12 which holds the back surface of the chip 10 by suction, etc., the carrier 16 which holds and conveys the board | substrate 14, and the supply station which supplies the chip 10. 52, an up-and-down camera 60 for detecting positions of the substrate 14 and the chip 10, a correction camera 30 that can be used to correct positional shifts in bonding, and a target moving mechanism ( And a target device 32 as a positional reference held by 54, and a control device unit 100 for controlling the operation of these elements.

The chip 10 is an LSI chip, and bumps containing gold as a main component are provided on the pads of the input / output terminals. The board | substrate 14 is a film board | substrate with which the conductor pattern is wired to the plastic film for electronic components, The metal layer which has tin as a main component is provided in the wiring pattern part to which the bump of the chip 10 is connected. Bonding can be performed by positioning a bump containing gold as a main component on the metal layer containing tin as a main component and pressing at a temperature of about 500 ° C. That is, the bonding apparatus 50 for COF has the function of bonding the chip | tip 10 to the board | substrate 14 by positioning between the chip | tip 10 and the board | substrate 4, and heating pressurization. to be.

The bonding tool 12 is a quadrangular horn-shaped member having a chip holding portion at its tip, and is provided with a vacuum suction hole through the chip holding portion at the center thereof. The chip holding portion is controlled by the controller 100. Suction holding of the chip 10 can be performed. In addition, the bonding tool 12 may incorporate a heater therein, and may heat the chip 10 at, for example, about 500 ° C. The control of the temperature is also performed by the controller 100.

The bonding tool 12 is mounted in a moving mechanism not shown, and can move in the X, Y, and Z directions shown in FIG. 2 under the control of the control device unit 100.

Specifically, the position where the pick-up position 90 which is the position which picks up the chip 10 from the supply station 52, and the position between the chip | tip 10 and the board | substrate 14 is performed, and it is a position which performs bonding after that is The position can be moved between the positioning and bonding position 92 and the correction position 94 for obtaining a correction amount for positioning. In each position, the bonding tool 12 can carry out the shank movement of Z direction, and can perform a horizontal movement or inclination movement between each position.

The carrier 16 is a jig holding the substrate 14 and is conveyed in the Y direction by a conveyance mechanism such as a conveyor (not shown). The control of conveyance is performed by the control apparatus part 100, and the board | substrate 14 is conveyed from a supply hole and stops at the positioning and bonding position 92. FIG.

After the positioning between the chip 10 and the substrate 14 and the bonding of the chip 10 are performed in the positioning and bonding position 92, the substrate is conveyed toward the discharge port and the next substrate is conveyed at the same time. It comes to a stop at the positioning and bonding position 92.

The up-and-down camera 60 is an optical component provided with two cameras inside. 3 shows an internal configuration of the vertical camera 60.

The upper and lower cameras 60 include a first camera 26, a second camera 28, reflectors 62 and 64, and a double-sided reflector 66 inside a suitable housing.

In the imaging device having the CCD (Charge Coupled Device), the first camera 26 and the second camera 28 may have their openings facing the + X axis direction together, and the center of the upper and lower cameras 60 in the X direction. It is placed in a position symmetrical about the axis.

The reflecting mirrors 62 and 64 have inclinations of -45 degrees and +45 degrees on the Z axis with respect to the X axis, respectively, and are disposed symmetrically with respect to the central axis in the X direction of the upper and lower cameras 60, respectively.

The double-sided reflector 66 has a 45-degree inclination with respect to the XY plane, and the position where the center axis in the X direction of the up-and-down camera 60 intersects the line connecting the reflector 62 and the reflector 64. Is placed on.

The operation of the upper and lower cameras 60 of such an internal configuration will be described. The optical axis representing the imaging center of the first camera 26 faces the + X direction from its opening, the 90 degree direction is changed in the reflecting mirror 62, and the one direction is directed toward the Y reflecting surface. The 90 degree direction is changed to face the + Z direction. That is, it becomes the upward optical axis 22, and faces the exterior of the up-and-down camera 60. FIG. On the other hand, the optical axis indicating the imaging center of the second camera 28 faces the + X direction from the opening, the 90 degree direction is changed in the reflecting mirror 62 to the + Y direction, and the lower half of the double-side reflecting mirror 66. The 90 degree direction changes from the slope to the -Z direction. That is, it becomes the downward optical axis 24 and faces the exterior of the up-and-down camera 60.

In this way, the up-and-down camera 60 moves the optical axis 22 indicating the imaging center of the first camera 26 upward and the optical axis 24 indicating the imaging center of the second camera 28 downward. Has the function of heading. The up-and-down camera 60 can attach the optical axis 22 and the optical axis 24 to the housing so that a direction may reverse in the reverse direction, and that axis may coincide at the time of assembly.

When the first camera 26 and the second camera 28 have the same performance, the height position of the upper and lower cameras 60 is the height position Z _{1 of the} substrate 14 and the substrate 14. It is set at the mid-height position of the height position (Z ₂₎ of the chip 10 in the positioning. In the positioning of the chip 10 held by the substrate 14 and the bonding tool 12, the first camera 26 focuses on the surface of the chip 10, and the second camera 28 In order to focus on the surface of the substrate 14, the whole optical system is designed.

The up-and-down camera 60 is usually retracted to the retracted position 96 which does not interfere with a bonding operation, and can move to the X direction from the position by control of the control apparatus part 100. FIG. Specifically, it can move to the positioning and bonding position 92 and the correction position 94. FIG.

The camera 30 for correction is arrange | positioned in the correction position 94 in the imaging device which has a CCD. The opening faces upward, that is, in the + Z direction, and the height position is set so that the focusing position is at the height Z ₁ of the surface of the substrate 14. Alternatively, the correction camera 30 may be a telecentric optical system.

The target 32 is a reference pin held by the target movement mechanism 54 and whose tip is the position reference. The target 32 is a tapered pin with a tapered tip, such as a capillary that can be used for wire bonding, and the tip 32 can be used, for example, a round or hemispherical shape having a diameter of about 15 μm. have. The target 32 has its longitudinal axis arranged in parallel with the XY plane. The direction of the longitudinal axis of the target 32 can be made parallel to the Y axis, for example, as shown in FIG. As the target 32, a metal material or a ceramic material processed into a predetermined shape can be used.

The target movement mechanism 54 can use a motor etc. in the mechanism which moves the target 32 to Z direction under control of the control apparatus part 100. FIG. The movement range of the target 32 is between the height position Z ₁ of the substrate 14 and the upper portion of the correction camera 30.

The target may be other than the reference pin shape as long as the target can be observed as a position reference from both the camera 30 for correction and the second camera 28. As another example, you may use the target 33 in which the cross hair pattern used as a position reference | standard is provided on the thin transparent board shown in FIG. The target 33 is provided with a cross hair pattern by etching or the like on a thin transparent plate such as a thin plastic plate or a thin glass plate. The position reference may be a pattern other than the cross hair pattern as long as it is a stable pattern that can be measured with sufficient accuracy. Positional reference such as a cross hair pattern is provided on the upper surface of the target 33, that is, the surface where the bonding tool 12 faces each other, and the height position is set at the height position Z ₁ of the substrate 14. do.

As another target, for example, the base material of the target 32 may be made a thin opaque plate, and the position reference may be provided on both surfaces.

Next, the structure of the control apparatus part 100 is demonstrated. The control device 100 has a function of controlling each element constituting the bonding device, and in particular, from the first camera 26 and the second camera 28 and the correction camera 30 inside the upper and lower cameras 60. A device having a function of acquiring image data and performing correction in positioning and positioning based on these data can be configured by a general computer.

Specifically, in the correction position 94, the operation of the up-and-down camera 60 and the bonding tool 12 is controlled, and the required imaging data is acquired from three cameras of the correction camera 30 and the up-and-down camera 60. FIG. Then, these data are processed and the position shift in bonding is calculated. In addition, by controlling the operation of the target moving mechanism 54, the target 32 has a function of evacuating after the imaging is completed. In addition, in the positioning and bonding position 92, the upper and lower cameras 60 and the bonding tool 12 control the operation of the carrier 16 when necessary, acquire necessary correction data from the upper and lower cameras 60, and correct them. It has a function of performing relative positioning of the chip | tip 10 held by the board | substrate 14 and the bonding tool 12, and performing a bonding operation so that the position shift in the bonding calculated in the position 94 may be corrected. . In order to perform the processing corresponding to these functions, software can be used, and predetermined processing can be performed by executing a corresponding position shift correction program and a bonding program. Some of the processing may be performed in hardware.

The control unit 100 includes a CPU 102, an input unit 104 such as a keyboard, an output unit 106 that is a display such as a display panel, a storage device 108, and a bonding tool 12. Bonding tool control unit 110 for controlling the operation of the control unit, a correction camera control unit 112 for controlling the imaging operation of the correction camera 30 to receive the imaging data, and a target control unit for controlling the movement of the target 32. 114 and an up-and-down camera controller 116 that controls the operation of the up-and-down camera 60 and controls the imaging operation of the first camera 26 and the second camera 28 therein to receive the imaging data. And they are joined together in an internal bus.

The CPU 102 includes a position shift correction unit 120, a positioning unit 122, and a bonding processing unit 124. The first position deviation measuring module 130 to the position shift calculating module 138 in the position shift correcting unit 120 include four positions corresponding to X ₁ , X ₂ , X ₃ , and X ₄ described in the principles of the present invention. The deviation vector is calculated and a two-dimensional correction amount? (X, Y) is obtained. These are demonstrated using FIGS. 5-13.

FIG. 5 shows the top and bottom cameras 60, the substrate 14 held in the carrier 16, the target 32, and the calibration camera 30 and the chip 10 underneath the components of the bonding apparatus 50. It is a figure which shows typically the planar arrangement of the bonding tool 12 which has (). Fig. 6 is a diagram schematically showing the side arrangement of these components. 5 and 6 show an initial state of the bonding apparatus 50. That is, in the positioning and bonding position 92, the board | substrate 14 is provided in the correction position 94 with the target 32 and the camera 30 for correction | amendment. In addition, the upper and lower cameras 60 may be in the retracted position 96, and the bonding tool 12 may be in the pickup position 90 or the like. However, the upper and lower cameras 60 retreat to the neighboring position of the positioning and bonding position 92 in order to indicate that the initial state. I assume that there is. In addition, the arrangement | positioning state of the bonding tool 12 and the up-and-down camera 60 in the positioning and bonding position 92 is shown with the broken line.

The first position deviation measurement module 130, the second position deviation measurement module 132, and the third position deviation measurement module 134 of the CPU 102 are all processed at the same time in the correction position 94. For the sake of convenience, the processing is performed in the order of the second position deviation measurement and the third position deviation measurement from the first position deviation measurement module 130.

For these processes, the bonding tool 12 and the vertical camera 60 are moved to the correction position 94, and the target 32 is set at the height of the height Z ₁ of the substrate 14. Specifically, the following is executed by the function of the control device unit 100, in particular, by the function of the first position deviation measuring module 130 that first performs a process relating to correction. That is, a command is given to the bonding tool control unit 110 and the bonding tool 12 is moved to the correction position 94. The height of the bonding tool 12 is set so that the bonding surface of the chip 10 may reach Z ₂ , which is the height of the focusing position of the first camera 26. Then, the upper and lower camera control unit 116 is instructed to move the upper and lower cameras 60 to the correction position 94. The height position of the upper and lower cameras 60 is focused on the bonding surface of the chip 10 of the bonding tool 12 by the first camera 26 as described above, and the second camera 28 is the substrate 14. Is set to focus on the height Z ₁ . Furthermore, a command is given to the target control unit 114, and the target moving mechanism 54 is driven to set the target 32 at the height of Z ₁ , which is the height position of the substrate 14. FIG. 7 is a diagram showing the arrangement status of each element in the correction position 94 thus set.

In this state, the first position deviation measuring module 130 further has a function of imaging the target 32 with the correction camera 30 and calculating the first position deviation based on the captured image data. Specifically, a command is given to the correction camera control unit 112, an image capturing instruction is issued, image data is acquired, and the captured image data is transmitted to the first position deviation measurement module 130. Then, the first positional deviation is obtained based on the transferred image data.

8 is a view from the image pickup data obtained by the correction camera 30 describes the image to obtain the first position deviation (X _1, Y _1). The captured image data is actually data obtained by capturing the target 32 and the chip 10 with the correction camera 30 facing upward (+ Z direction). However, in FIG. 8, for convenience of description, the upper portion of the correction position 94 The figure is converted into the data when viewed. Similarly, also in the imaging data of FIG. 10, FIG. 12, etc. below, it showed uniformly to the data when it sees from the upper side of the correction position 94. As shown in FIG. In the imaging data 150 of FIG. 8, there is a cross pattern 152 showing the imaging center of the correction camera 30 at the center of the field of view, and at the lower left of the substrate 14 at the height position Z ₁ of the substrate 14. There is an image picked up pattern 154 of the target 32. The intersection of the cross pattern 152 showing the imaging center of the correction camera 30 is an imaging reference position of the correction camera 30, and the tip of the target pattern 154 is the position reference P of the target 32. ₀ ).

The first positional deviations X ₁ and Y ₁ are given as the reference position using the intersection point of the cross pattern 152 as a vector from the reference position toward the position reference P ₀ of the pattern 154 of the target. For one-dimensional, then the distance to the reference position of the target 32 from the position of the optical axis 31 represents the image sensing center of the correction camera 30, and X ₁ is described in the principles of the invention.

In the state of FIG. 7 of the correction position 94, the 2nd position deviation measuring module 132 picks up the target 32 with the 2nd camera 28, and makes the 2nd position deviation based on the imaging data. Has the function to obtain. Specifically, a command is given to the upper and lower camera control unit 116, an imaging instruction is given to the second camera 28, the imaging data is acquired, and the acquired imaging data is transmitted to the second position deviation measurement module 132. . Then, the second positional deviation is obtained based on the transferred image data.

9 is a second diagram from the image pickup data obtained by the camera 28 is described for the shape to obtain a second position deviation (X _2, Y _2).

In the imaging data 156 of FIG. 9, there is a cross pattern 158 showing the imaging center of the second camera 28 at the center of the field of view, and the image 160 of the target 32 is captured on the right side thereof. have.

The intersection of the cross pattern 158 showing the imaging center of the second camera 28 is the imaging reference position of the second camera 28, and the tip of the target pattern 160 is the reference of the position of the target 32. (P ₁ ) is shown.

The second position deviation X ₂ , Y ₂ is based on the intersection of the cross pattern 158 showing the imaging center of the second camera 28 as a reference position, and from the reference position, the position reference of the pattern 160 of the target. Given as a vector towards (P ₁ ). For one-dimensional, the second is the distance to the reference position of the target 32 from the position of the optical axis (24) indicating the image pickup center of the second camera 28, and the X ₂ described in the principles of the invention.

In the state of FIG. 7 of the correction position 94, the 3rd position deviation measuring module 134 makes the bonding tool 12 which hold | maintains the chip | tip 10 image with the 1st camera 26, and inputs it to the image data. It has a function to calculate the third position deviation on the basis. Specifically, a command is given to the up-and-down camera control unit 116 to issue an imaging instruction to the first camera 26, to acquire the imaging data, and to transmit the acquired imaging data to the third position deviation measurement module 134. . Then, the third positional deviation is obtained based on the transferred image data.

10 is a view for explaining the first to obtain a third position error (X _3, Y ₃₎ from the image pickup data obtained by the camera (26) shape. In the imaging data 162 of FIG. 10, there is a cross pattern 164 showing the imaging center of the first camera 26 at the center of the field of view, and the chip 10u at the height Z ₂ on the right side thereof. Is the edge of the captured reference pattern 166u. As described above, the subscript u is used to distinguish between the chip and the height position when determining the fourth positional deviation described later. As a reference pattern of the chip 10u, the same thing as the case of the 4th position deviation measurement mentioned later should just be used. For example, the shape pattern of a specific electrode pad or the specific edge shape pattern of the chip 10 can be used. The intersection of the cross pattern 164 showing the imaging center of the first camera 26 is the imaging reference position of the first camera 26, and the edge of the reference pattern 166u of the chip is the reference of the chip 10u. To show the location.

The third position deviation X ₃ , Y ₃ is based on the intersection of the cross pattern 164 showing the imaging center of the first camera 26 as a reference position, and the chip at the height Z ₂ from the reference position. It is given as a vector facing the edge of the reference pattern 166u of (10u). In the one-dimensional case, the distance is from the position of the optical axis 22 representing the imaging center of the first camera 26 to the reference position of the chip 10u at the height Z ₂ , which is the principle of the present invention. X ₃ is explained.

In the above, the processing to obtain the first position deviation, and a process to obtain a second position deviation, and with an imaging process of the target 32 in the height (Z _1). As described in the principles of the present invention, the target 32 includes the position shift Xc between the optical axis 22 of the first camera 26 and the optical axis 24 of the second camera, and the bonding tool 12. Since it becomes a position reference | standard when calculating position shift Xn at the time of vertical movement, it is calculated | required that the position does not change between position shift correction processes.

In practice, the position of the target 32 is changed during the position shift correction process by the change with the passage of time of the holding of the target moving mechanism 54 holding the target 32 and the heat from the high temperature bonding tool 12. There will be a change in the degree that affects the correction process. There, it is preferable to perform the imaging process of the target 32 for obtaining the 1st position deviation, and the imaging process of the target 32 for obtaining the 2nd position deviation simultaneously. Specifically, simultaneous image processing instruction for the second camera 28 from the upper and lower camera control unit 116 and the imaging instruction for the camera 30 for correction from the camera control unit 112 for correction are simultaneously and simultaneously performed. If not possible, the process is performed at the closest time possible. Then, the imaged data is stored once in the storage device 108 or the like, and thereafter, image data processing for obtaining each position deviation and necessary arithmetic processing are performed.

Subsequent to the process of calculating the third position deviation from the first position deviation, after each imaging process for obtaining the third position deviation from at least the first position deviation, the fourth position deviation measuring module 136 performs the substrate 14. At the height Z ₁ , the bonding tool 12d having the chip 10d is imaged by the correction camera 30, and has a function of determining the fourth positional deviation based on the captured image data. Specifically, the following plurality of processes are performed. That is, a command is given to the up-and-down camera control unit 116, and the up-and-down camera 60 is moved to the retracted position 96. Then, a command is given to the target control unit 114, and the target moving mechanism 54 is driven to lower the target 32 closer to the upper side of the camera 30 for correction. Thereafter, a command is given to the bonding tool control unit 110 so that the height of the bonding tool 12 is lowered so that the bonding surface of the chip 10 reaches Z ₁ , which is the height of the substrate 14. FIG. 11 is a diagram showing the arrangement status of each element in the correction position 94 thus set.

Dropping the target 32 closer to the upper side of the correction camera 30 from Z ₁ , which is the height of the substrate 14, does not prevent the bonding tool 12 from descending at a height Z ₁ . To make it possible. As a result, a bonding surface of the chip 10 can be accurately set at a height (Z _1). This object is to separate the target 32 from the bonding tool 12 which descends as much as possible, and to reduce the influence of the heat from the high temperature bonding tool 12 even if it is evacuating. In addition, the target 32 is not aligned from the focusing position of the correction camera 30 even when it is in this way as close to the upper side of the correction camera 30, so that the bonding tool 12 of the correction camera 30 This is because it does not disturb the imaging. Further, the retraction of the target 32 is performed by the movement in the height direction instead of the movement in the horizontal direction, so that the reproducibility of the position in the XY plane before and after the retraction of the target 32 is determined by the horizontal movement. It is because it is better compared with a method.

In this state, the fourth position deviation measuring module 136 further captures the bonding tool 12 holding the chip 10 with the correction camera 30 and detects the fourth position deviation based on the captured image data. Has the function to obtain.

Specifically, a command is given to the correction camera control unit 112, an image capturing instruction is issued to the correction camera 30, the image capturing data is acquired, and the acquired image capturing data is transmitted to the fourth position deviation measuring module 134. Then, the fourth positional deviation is obtained based on the transferred image data.

12 is a view from the image pickup data obtained by the correction camera 30 describes the image to obtain a fourth position deviations (X _4, Y _4). In the imaging data 150 of FIG. 12, there is a cross pattern 152 showing the imaging center of the correction camera 30 at the center of the field of view. This is the same as the case of the field of view of the correction camera 30 in FIG. On the right side thereof, there is an edge of the captured reference pattern 168d of the chip 10d at the height Z ₁ . Here, the subscript d is used to distinguish between the chip and the height position when the above-described third positional deviation is obtained. As the reference pattern of the chip 10d, the same one as in the above-described third position deviation measurement is used. The intersection of the cross pattern 152 showing the imaging center of the correction camera 30 is the imaging reference position of the correction camera 30, and the edge of the reference pattern 168d of the chip indicates the reference position of the chip 10d. It is to illustrate. In addition, with appropriately located standard (P ₀₎ of the target 32 is measured at 8 as a reference.

The fourth position deviation X ₄ , Y ₄ is based on the intersection of the cross pattern 152 showing the imaging center of the correction camera 30 as a reference position, and the chip at the height Z ₁ from the reference position. 10d) as the vector facing the edge of the reference pattern 168d. In the one-dimensional case, the distance is from the position of the optical axis 31 indicating the imaging center of the correction camera 30 to the reference position of the chip 10d at the height Z ₁ . X ₄ is described.

The first position deviation (X ₁ , Y ₁ ), the second position deviation (X ₂ , Y ₂ ), the third position deviation (X ₃ , Y ₃ ) and the fourth position deviation (X ₄ , Y ₄ ) obtained in this way Is sent to the position shift calculation module 138. The position shift calculation module 138 has a function of calculating correction amounts Δ (X, Y) for correcting the position shift in bonding using these data. Correction amount (DELTA) (X, Y) is given by Formula (3) which extended Formula (2) demonstrated by the principle of this invention to two dimensions.

△ (X, Y) = (X ₃ , Y ₃ )-[(X ₂ , Y ₂ )-(X ₁ , Y ₁ ) + (X ₄ , Y ₄ )] ... (3)

Next, the positioning unit 122 positions the substrate 14 and the chip 10 by using the correction amounts Δ (X, Y) requested as described above so that there is no positional shift in the bonding. Has the function. Specifically, it includes some of the following functions. First, a command is given to the bonding tool control unit 110 to move the bonding tool 12 to the positioning / bonding position 92. The height position of the surface of the chip 10 held in the bonding tool 12 is set at Z ₂ . In addition, a command is given to the vertical camera control unit 116 to move the vertical camera 60 to the positioning / bonding position 92. Then, the imaging instruction is given to the first camera 26 and the second camera 28 included in the upper and lower cameras 60, and the chip 10 held in the bonding tool 12 with respect to the first camera 26. Image pickup and the second camera 28 are imaged on the substrate 14, and the image pickup data is transferred to the positioning unit 122. Based on the transferred image data and the correction amount Δ (X, Y) requested a while ago, the position shift is corrected, and the result is commanded to the bonding tool control unit 110, whereby the reference of the substrate 14 The position and the reference position of the chip 10 held in the bonding tool 12 are positioned. In addition, the positional relationship of the bonding tool 12 holding the chip | tip 10, the board | substrate 14, and the up-and-down camera 60 at the time of positioning is shown with the broken line in FIG.

FIG. 13: is a figure explaining the shape which positions and processes correction amount (DELTA) (X, Y) in the visual field of the 1st camera 26. FIG. Now, when moving from the correction position 94 to the positioning bonding position 92, the imaging data 162 of the 1st camera 26 in the positioning bonding position 92 is a correction position 94 In Fig. 10). In this case, between the intersection of the cross pattern 164 indicating the imaging center of the first camera 26 and the edge of the reference pattern 166u which is the reference position of the chip 10u, the third position deviation X ₃ ,. Y ₃ ) away. Now, for the sake of simplicity, the reference position of the substrate 14 is assumed to coincide with the imaging center of the second camera 28. In this case, the positioning of the imaging center of the first camera 26 and the reference position of the chip 10 does not correct only the third positional deviations X3 and Y3, but the imaging center of the first camera 26. From the above, the reference position of the chip 10 is moved to the position of the correction amounts Δ (X, Y). By doing in this way, the positioning which correct | amends the position shift in bonding according to Formula (3) can be performed.

In order to show the relationship with the correction amounts Δ (X, Y), the first position deviations X ₁ , Y ₁ and the second position deviations X ₂ , obtained in FIG. 13, respectively in FIGS. 8, 9, and 12, respectively. X ₂ ) and the fourth positional deviations X ₄ , X ₄ are also shown. In addition, when the reference position of the board | substrate 14 does not correspond with the imaging center of the 2nd camera 28, the same correction | amendment can be performed by moving the reference position of the 1st camera 26 as much as the mismatch.

After performing the positioning to correct the positional shift in the bonding, the bonding processing unit 124 has a function of bonding the chip 10 to the substrate 14. Specifically, it includes some of the following functions. After the above positioning is performed in the positioning and bonding position 92, the upper and lower camera control unit 116 is instructed, and the upper and lower camera 60 is retracted to the retracted position 96. Next, a command is given to the bonding tool control unit 110, the bonding tool 12 holding the chip 10 is dropped, the bumps of the chip 10 are brought into contact with the substrate 14, and bonding is performed by pressure heating. do. When the bonding process is finished, vacuum suction of the bonding tool 12 is stopped and the bonding tool 12 is raised.

In this way, the imaging process of the target 32 is performed substantially simultaneously, and the influence of the change with the passage of time of the position between the correction processes of the target 32 which is a position reference | standard can be suppressed. That is, once data collection regarding the position of the target 32 is completed, the position of the virtually universal target 32 which has never changed environment or time can be determined by the data. Subsequently, the position shift correction amount can be obtained based on the position of this virtual target 32.

In addition, once the position of the virtual target 32 is determined in this way, the target 32 may be evacuated to an arbitrary position. Therefore, the target 32 can be retracted where it does not prevent the bonding tool 12 holding the chip 10 from lowering to the position of the height Z ₁ of the substrate 14. Thus, when the fourth positional deviation is obtained, the bonding tool 12 holding the chip 10 can be accurately lowered to the position of the height Z ₁ of the substrate 14. Moreover, the target 32 does not contact the high temperature bonding tool 12 by this, and it does not deteriorate the position precision.

Therefore, at the time of positioning a chip | tip and a board | substrate in bonding, the amount of shift | offset | difference between two cameras and the amount of shift | offset | difference by the movement of a bonding tool can be corrected correctly, and the position shift in bonding can be made smaller.

According to the above configuration, the positioning mechanism having the first camera and the second camera further includes a target having a positional reference and a correcting camera, in order to correct the positional misalignment. The first positional deviation between the reference position, the second positional deviation between the positional reference of the target and the imaging reference position of the second camera, and between the reference position of the object with respect to the bonding tool and the imaging reference position of the first camera And a fourth positional deviation between the reference position of the object with respect to the bonding tool and the imaging reference position of the camera for correction. Since the fourth position deviation from the first position deviation corresponds to X ₁ , X ₂ , X ₃ , and X ₄ described in the principles of the present invention, the position shift in bonding is obtained based on these and corrected. Therefore, positional shift in bonding can be made smaller.

At this time, the target is picked up by the second camera and the correction camera, but the imaging is performed at substantially the same time. Therefore, the change in the position of the target during the correction operation is changed in accordance with the image pickup data. Influence on output can be suppressed. For example, in the case where the bonding apparatus has a heater or the like, the position of the target may change even during the correction operation by the high environmental temperature. Regarding such a change over time, by performing all of the imaging required for the target at about the same time, the influence due to the difference in the acquisition time of the imaging data can be eliminated.

In addition, since the target is to be retracted from the imaging position after the imaging data and the like are stored, in order to obtain the fourth positional deviation, in spite of the disturbance of the setting of the height position of the object with respect to the bonding tool, for example, imaging of the target is performed. It is also possible to accurately set the height of the object with respect to the bonding tool at the height of the position. Further, the target is sufficiently separated from the bonding tool to be evacuated, so that the influence of temperature, for example, when the bonding tool is at a high temperature, does not reach the target.

Further, since the target moves in the height direction and retracts, the reproducibility of the position in the horizontal plane can be improved as compared with the target retracting in the horizontal direction. In addition, since it retracts to the height deviating from the focusing position of the camera for correction, it does not affect the imaging data of the camera for correction.

In addition, since the target is a reference pin having a longitudinal axis in the horizontal plane, the target can be easily produced as a position reference, and compared with the case where the target of the transparent plate is used, such as refraction when light passes through the transparent plate, etc. No influence

Moreover, a target is arrange | positioned at the height substantially equal to the height where a board | substrate is arrange | positioned. The object with respect to a bonding tool is arrange | positioned at the height which is substantially the same as the height where a board | substrate is arrange | positioned, and a 4th position deviation is calculated | required. Thereby, as described in the principle of the present invention, the amount of correction when the shift (+ Xn) due to the movement in the height direction of the bonding tool and the shift (+ Xc) between the two cameras for positioning are present together X = Xc + Xn is found and these are corrected. Therefore, positional shift in bonding can be made smaller.

Claims (6)

Measuring the position of the first camera and the substrate measuring the position of the object with respect to the bonding tool as at least one of the bonding object held by the bonding tool or the bonding tool or the measuring member held by the bonding tool. In the bonding apparatus provided with the positioning mechanism containing the 2nd camera to perform, and positioning by the positioning mechanism the bonding object hold | maintained by a bonding tool at the determined position of the board | substrate arrange | positioned at the bonding work surface, and bonding. Positioning mechanism, moreover, Targets that can be viewed from both sides with positional criteria, A camera for correction arranged in a predetermined positional relationship on one side of the target, First measuring means for picking up the target by the camera for correction and obtaining a first positional deviation between the target position reference and the image pickup reference position of the correction camera in the image pickup data; The second camera is placed on the other side of the target in a predetermined positional relationship, the target is imaged by the second camera, and the second positional deviation between the positional reference of the target and the imaging reference position of the second camera in the imaging data. The second measuring means obtained; The first camera is opposed to the object relating to the bonding tool in a predetermined positional relationship, the first camera captures an object related to the bonding tool, and the reference position of the object relating to the bonding tool in the imaging data and the imaging reference of the first camera. Third measuring means for obtaining a third positional deviation between the positions; The object relating to the bonding tool is disposed on the other side of the target in a predetermined positional relationship, the object for the bonding tool is imaged by the camera for correction, and the reference position of the object for the bonding tool in the imaging data and the imaging reference for the camera for correction. Fourth measuring means for obtaining a fourth positional deviation between the positions; Calculating means for calculating a positional shift in bonding based on the first positional deviation, the second positional deviation, the third positional deviation, and the fourth positional deviation; A means for correcting the positional shift in bonding and performing positioning based on the calculation result; The bonding apparatus according to claim 1, wherein the imaging of the target in the first measuring means and the imaging of the target in the second measuring means are performed at substantially the same time. The method of claim 1, Storage means for storing the imaging data of the target or data based thereon; The target device can be retracted from an imaging position after the imaging data or the data based thereon is stored. The method of claim 2, And the target moves in the height direction and retracts at a height deviated from the focusing position of the correction camera. The method of claim 1, And the target is a reference pin having a longitudinal axis disposed in the horizontal plane. The method of claim 1, The target is arranged at a height substantially equal to the height at which the substrate is placed. The method of claim 1, The 4th measuring means arrange | positions the object with respect to a bonding tool in the height which is substantially the same height as the board | substrate is arrange | positioned, and the bonding apparatus characterized by the above-mentioned.

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