KR20200135260A - Die bonding apparatus and manufacturing method of semiconductor device - Google Patents

Abstract

The present invention provides a die bonding apparatus which further improves positioning accuracy. The die bonding apparatus includes a bonding head which mounts a picked die on a substrate; a target marker which emits light formed in an upper part of the bonding head; and an imaging device which images the position recognition mark and the target marker of the substrate. The imaging device images the target marker in a defocused state.

Description

TECHNICAL FIELD The manufacturing method of a die bonding device and a semiconductor device TECHNICAL FIELD

The present disclosure relates to a die bonding apparatus, and is applicable to, for example, a die bonder having a camera that recognizes a substrate.

Part of the manufacturing process of a semiconductor device includes a process of assembling a package by mounting a semiconductor chip (hereinafter, simply referred to as a die) on a wiring board or lead frame (hereinafter, simply referred to as a substrate). Some include a process of dividing a die from a semiconductor wafer (hereinafter simply referred to as a wafer) (a dicing process), and a die bonding process of mounting the divided die on a substrate. A semiconductor manufacturing apparatus used in the die bonding process is a die bonding apparatus such as a die bonder.

The die bonder is an apparatus for bonding (mounting and bonding) a die onto a substrate or an already bonded die using solder, gold plating, or resin as a bonding material. In a die bonder that bonds a die to the surface of a substrate, for example, the die is picked up by adsorbing it from the wafer using a suction nozzle called a collet (pick-up process), conveying it onto the substrate, and applying a pressing force. , The bonding is performed by heating the bonding material (bonding process), and the operation (operation) is repeatedly performed.

In the above-described pick-up process and bonding process, the dyna substrate is imaged by an imaging device according to each process, and positioning and inspection are performed by image processing based on the captured image.

Japanese Patent Publication No. 2016-171107 Japanese Patent Publication No. 2016-197629 Japanese Patent Publication No. 2016-197630

However, with the recent development of chip-on-chip stacking technology due to package miniaturization and thickness reduction and die thickness reduction, die bonding requires more stringent single-digit order µm positioning. In order to increase the positioning accuracy, it is important to accurately grasp the positions of mounting units such as bonding heads and imaging systems involved in the bonding process and the posture defined by the rotation angle.

An object of the present disclosure is to provide a die bonding device that further improves positioning accuracy.

Other problems and novel features will become apparent from the description of the present specification and the accompanying drawings.

A brief overview of representative ones of the present disclosure is as follows.

That is, the die bonding device includes a bonding head for loading a picked up die on a substrate, a target marker that emits light provided on the bonding head, and an imaging device for imaging the position recognition mark and the target marker of the substrate. Equipped. The imaging device captures an image of the target marker while the focus is out of focus.

According to the die bonding device, positioning accuracy can be further improved.

1 is a diagram for explaining a coordinate system of a bonding head and a camera.
2 is a diagram illustrating a method of aligning a bonding head and a coordinate system of a camera.
Fig. 3 is a diagram for explaining the effect of pitching on the Z-axis caused by the motion of the bonding head in the X-axis or Y-axis.
4 is a diagram explaining displacement of a bonding head.
5 is a diagram showing a relationship between a camera, a bonding head, and a substrate according to the embodiment.
Fig. 6 is a diagram for explaining a relationship between a light emission target marker and a position alignment mark.
Fig. 7 is a diagram showing a captured image of the light emission target marker in Fig. 6;
Fig. 8 is a diagram showing a configuration example of a light emission target marker.
Fig. 9 is a diagram for explaining a comparison between a light emission target marker according to an embodiment and another target marker.
Fig. 10 is a diagram explaining a positional displacement of a bonding head.
Fig. 11 is a diagram for explaining a light emission target marker of a first modification.
Fig. 12 is a diagram for explaining a light emission target marker of a second modification.
Fig. 13 is a diagram explaining measurement of inclination of a bonding head.
Fig. 14 is a diagram explaining measurement of inclination of a bonding head.
Fig. 15 is a diagram for explaining a light emission target marker of a third modification.
Fig. 16 is a diagram showing a configuration example of a light emission target marker according to a fourth modification.
Fig. 17 is a diagram for explaining overlapping of adjacent circular shapes.
Fig. 18 is a schematic top view showing a configuration example of a die bonder of the embodiment.
FIG. 19 is a diagram explaining a schematic configuration when viewed from the direction of arrow A in FIG. 18;
Fig. 20 is an external perspective view showing the configuration of the die supply unit of Fig. 18;
Fig. 21 is a schematic cross-sectional view showing an essential part of the die supply section of Fig. 18;
Fig. 22 is a block diagram showing a schematic configuration of a control system of the die bonder of Fig. 18;
Fig. 23 is a flowchart for explaining a die bonding process in the die bonder of Fig. 18;

Hereinafter, embodiments, modifications, and examples will be described with reference to the drawings. However, in the following description, the same constituent elements are denoted by the same reference numerals, and repeated explanations may be omitted. In addition, in order to make the explanation more clear, the drawings may be schematically expressed with respect to the width, thickness, shape, etc. of each part compared to the actual mode, but are only examples and do not limit the interpretation of the present invention. .

First, the problem of positioning will be described using FIGS. 1 to 4. 1 is a diagram illustrating a coordinate system of a bonding head and a camera. 2 is a diagram for explaining a method of aligning the bonding head and the camera coordinate system. FIG. 3 is a diagram for explaining the effect of pitching on the Z-axis caused by an X-axis or Y-axis motion of the bonding head. 4 is a diagram for explaining the displacement of the bonding head.

As shown in Fig. 1, a camera CA for imaging a work such as a substrate is mounted on an XY table DU1, and a bonding head HD is mounted on another XY table DU2. The bonding accuracy is stabilized by accurately grasping the position of the bonding head in the bonding apparatus. However, it is difficult to mechanically completely match the coordinate system of the bonding head HD mounted on different XY tables and the camera CA (optical system).

In order to accurately grasp the position of the bonding head HD, there is a method of forming a plurality of marks on the pressure-sensitive paper PSP with the bonding head HD to create a transformation matrix of two plane coordinate systems of the bonding head and the optical system. In this method, the influence of pitching and yawing of the XY table DU2 of the bonding head HD cannot be eliminated unless a considerable number of strokes are formed. Therefore, it is practically impossible to correct pitching and yawing by this method. In addition, when the mount or the like is thermally deformed and the positional relationship between the XY table DU2 of the bonding head HD and the XY table DU1 of the camera CA is changed, the influence cannot be removed. Also, it is not possible to monitor the position of the bonding head HD in real time.

As shown in Fig. 3, pitching generated by the motion of the X-axis or Y-axis of the bonding head HD affects the Z-axis. That is, the displacement of the elevation angle of the bonding head HD, the displacement in the elevation direction, and the displacement in the θ direction of the bonding head HD are also generated from pitching and yawing generated in the XY table DU2 on which the bonding head HD is mounted. A change in elevation angle affects the landing position of the bonding head HD (the landing position changes). Therefore, in order to realize accurate bonding, it is necessary to grasp the inclination (elevation angle) of the Z-axis of the bonding head HD mounted on the XY table, and as shown in FIG. 4, the displacement of the XY of the bonding head HD (the offset coordinate of XY). And also, the displacement of the Z (height of the head), the elevation angle (the elevation angle of the head (α)) and the elevation direction (the direction of the elevation angle of the head (β)), the displacement in the direction of the head itself (rotation of the head (θ)). Need to be detected.

<Embodiment>

Next, an embodiment that is an example of solving the above-described problem will be described with reference to FIGS. 5 to 8. 5 is a diagram showing a relationship between a camera, a bonding head, and a substrate according to an embodiment. 6 is a diagram for explaining a relationship between a light emission target marker and a position alignment mark. FIG. 7 is a diagram showing a captured image of the light emission target marker in FIG. 6. 8 is a diagram showing an example of the configuration of a light emission target marker.

As shown in Fig. 5, the target position (position recognition mark) TP on the substrate S and the coordinates of the bonding head are collectively monitored by the camera CA, which is an imaging device. Thereby, the coordinate system in the image of the camera CA can be uniformly managed, and an accurate offset amount can be calculated. In addition, since the position of the bonding head HD can be monitored in real time, it can respond to thermal deformation and the like.

In order to monitor the coordinates of the bonding head HD, as shown in Fig. 6, a light emission target marker LTM including an LED light source is installed on the bonding head HD, and the position thereof is detected by the camera CA. At this time, since the target on the substrate S is focused, the light emission target marker LTM is located at a distance Lh shorter than the focal length Lf of the camera CA, and the captured image is defocused as shown in FIG. A light source (light emission target marker LTM) is rounded to form a circular CI. The circular CI linearly follows the movement of the bonding head HD. Therefore, even with the circular CI of this out-of-focus, the relative position of the camera CA and the bonding head HD can be obtained. In addition, the circular CI is taken larger than the light source image when the focus is focused. The positioning accuracy in a circle that is taken as large is superior to that in a circle that is taken as small in image calculation. In general, in the case of a circle, the longer the circumferential length, which is the image boundary, has better positioning accuracy.

In addition, if the LED is mounted directly on the bonding head HD, the position of the light-emitting target marker LTM is moved due to the effect of self-heating during the light emission of the LED. As shown in Fig. 8, the light source LS, which is also a heat source, is used as the bonding head. It is preferable that the light is separated from the HD and guided by an optical fiber OF to the position of the light emission target marker LTM on the upper part of the bonding head HD. The position of the light-emitting target marker LTM can be stabilized by separating the target marker portion of the light-emitting light source from the heat source using an optical fiber.

Here, compare with other examples. FIG. 9 is a diagram for explaining a comparison between a light emission target marker and another target marker according to the embodiment, FIG. 9A is a diagram illustrating a case where the camera is focused on a target on the substrate, and FIG. B) is a diagram showing a case where the target marker of the first comparative example is mounted on the bonding head, and FIG. 9C is a diagram showing a case where the target marker of the second comparative example is mounted on the bonding head, and FIG. 9 FIG. 9(D) is a diagram showing a case where the bonding head of FIG. 9C is inclined, and FIG. 9(E) is a diagram showing a case where the light emission target marker of the embodiment is mounted on the bonding head.

From the following reasons, it can be said that the method of the embodiment using a light emitting light source as a target marker mounted on the bonding head HD is excellent.

The target on the substrate S is focused at the position of the camera CA shown in Fig. 9A.

As shown in Fig. 9B, when a conventional target marker TM that does not emit light in a glass vapor deposition type is mounted on the upper portion of the bonding head HD, the target marker TM is out of focus and thus an image is taken out of focus. The surroundings and images overlap, making it difficult to identify the target marker TM. In addition, it is necessary to separately install a lighting, so it illuminates the surroundings. Therefore, a peripheral design is required so that the target marker TM can float. As shown in Fig. 9E, in the embodiment in which an LED having a small light point is mounted and recognized (using a light emission target marker LTM), the contrast difference with the surroundings can be increased.

As shown in Fig. 9C, it is considered that a mirror MR, a prism, etc. are installed, and a target mark TM is mounted on the side of the bonding head HD to focus, but when a mirror MR or a prism is used, As shown in Fig. 9D, when the elevation angle of the bonding head HD is changed, it becomes difficult to grasp the position.

Next, correction of the positional displacement of the bonding head will be described with reference to FIG. 10. Fig. 10 is a diagram explaining the positional displacement of the bonding head, Figs. 10A and 10D are diagrams illustrating a case where the position is not displaced, and Fig. 10B is the bonding head in the positive Y-axis direction. It is a figure which shows the case where there is a position shift, FIG. 10C is a figure which shows the case where a bonding head is shifted in a negative Y-axis direction.

As shown in (B) and (C) of Fig. 10, when there is an increase or decrease in the movement amount of the bonding head HD, the light emission target marker LTM formed on the upper part of the bonding head HD is recognized by the camera CA to increase or decrease the movement amount ( Position shift amount) can be detected. By correcting that much, the bonding position can be accurately controlled.

According to the embodiment, one or more effects shown below are obtained.

(1) By measuring the positions of the work-in substrate and the bonding head with one camera, it becomes possible to detect the relative position in the coordinate system of one camera image. It is not necessary to perform unnecessary correction processing by aligning coordinates between cameras or units.

(2) The coordinates of the bonding head can be measured each time. Therefore, it becomes possible to reduce the dependence on the correction data generated before the start of construction.

(3) By using the light emission target marker, it becomes possible to stably obtain a captured image in a state that is not in focus.

(4) By accurately grasping the spatial position of the bonding head, it is possible to improve the bonding accuracy.

<modification example>

Hereinafter, some of the typical modified examples of the embodiment are illustrated. In the description of the following modification, it is assumed that the same reference numerals as those in the above-described embodiment can be used for portions having the same configuration and function as those described in the above-described embodiment. And for the description of such a part, it is assumed that the description in the above-described embodiment can be appropriately used within a range not technically contradictory. In addition, a part of the above-described embodiment, and all or part of a plurality of modified examples may be appropriately and complexly applied within a range not technically contradictory.

In the embodiment, there is only one light emission target mark to be mounted on the bonding head, but by mounting a plurality of light emission target marks, it becomes possible to measure the rotation, height, and elevation of the bonding head.

(1st modification)

The first modification is an example of measuring the rotation and height of the bonding head, and will be described with reference to FIG. 11.

Fig. 11 is a diagram explaining the light emission target marker of the first modification, Fig. 11A is a front view of the light emission target marker of the embodiment, and Fig. 11B is a front view of the light emission target marker of the first modification. , FIG. 11(C) is a front view of the emission target marker when the bonding head is rotating, FIG. 11D is a front view of the emission target mark when the bonding head is raised, and FIG. 11(E) ) Is a side view of the light emission target marker of the first modification, FIG. 11F is a captured image of FIG. 11A, and FIG. 11G is a captured image of FIG. 11B, and FIG. 11(H) is the captured image of FIG. 11(C), and FIG. 11(I) is the captured image of FIG. 11(D).

As shown in Figs. 11A and 11B, in the first modification, five light-emitting target markers smaller than the light-emitting target marker LTM of the embodiment are mounted on the bonding head HD. One luminescence target marker LTM1 is placed in the center, and four luminescence target markers LTM2, LTM3, LTM4, LTM5 are placed at equidistant all directions around it, and three luminescence target markers LTM1, LTM2, LTM3 are arranged in the first direction. Arrange it so that it is in a straight line. The three light-emitting target markers LTM1, LTM4, and LTM5 are arranged in a straight line in the second direction. The first direction is a direction orthogonal to the second direction. As shown in (A) (B) of Fig. 11, the height of the bonding head HD is the same, and as shown in (E) (F) of Fig. 11, the light emission target marker has a circular shape, and the first The circular shape of the light emission target markers LTM1 to LTM5 of the modified example is smaller than that of the light emission target marker LTM of the embodiment.

When the bonding head HD is rotated, as shown in FIG. 11(H), the positions of the plurality of light-emitting target markers positioned on a straight line are also rotated, so that θ can be measured. In addition, when the height of the bonding head HD is changed, the size of the image of the light emission target marker and the distance between the images of the light emission target marker also change, as shown in Fig. 11(I). The displacement of the Z (height) of the bonding head HD can be measured by measuring the change in the distance between the images of the emission target marker.

Further, the displacement of the Z (height) of the bonding head HD can be measured by measuring the size of the image of the light-emitting target marker.

By pluralizing the light emission target markers, the height of the bonding head and the displacement of the θ rotation can be detected.

(2nd modification)

The second modified example is an example of detecting the inclination component of the bonding head, and will be described with reference to FIGS. 12 to 14.

12 is a diagram for explaining a light emission target marker of a second modification. FIG. 13 is a diagram explaining measurement of the inclination of the bonding head, FIG. 13A is an image of a light emission target marker when there is no inclination in the bonding head, and FIG. 13B shows no inclination in the bonding head. It is an image of a light emission target marker when it is displaced in the XY direction, and FIG. 13(C) is an image of a light emission target marker when there is an inclination in the bonding head. 14 is a diagram for explaining measurement of the inclination of the bonding head, FIGS. 14A and 14D are diagrams showing a state in which the bonding head has no inclination, and FIG. 14B (C) is It is a diagram showing a state in which the head is inclined.

As shown in Fig. 12, the plurality of light-emitting target markers LTM have different installation heights (ΔH>0). In other words, the light emission target marker LTM is mounted at a position where the height of the upper portion of the bonding head HD is different. At this time, even if the size of the light emission target marker LTM is the same, the focal length is different, and thus the circular shape of the out of focus has different sizes as shown in Fig. 13A. By measuring the distance between the centers of this circular shape, it is possible to discriminate whether the bonding head HD is inclined or whether the moving distance of the bonding head HD is different. As shown in (B) of FIG. 13, when the image of the two light-emitting target markers LTM having different distances between subjects moves at an equidistant distance (Lb = La), the bonding head HD moves in the XY direction, and in FIG. 13(C) As shown in the figure, when the image distance of the two emission target markers LTM is changed (Lc≠La), it can be determined that the bonding head HD is inclined.

Therefore, as shown in (B) (C) of Fig. 14, when the bonding head HD is inclined, the elevation angle displacement and the elevation angle direction of the bonding head can be detected by changing the installation height of the plurality of light emission target markers. have.

(3rd modification)

The third modified example is an example of measuring the rotation, height, and inclination of the bonding head, and will be described with reference to FIG. 15. 15 is a diagram for explaining a light emission target marker of a third modification.

As shown in Fig. 15, the third modified example is an example combining the first modified example and the second modified example, and in the third modified example, five light emission target markers are bonded in the same arrangement as that of the first modified example. Mount on the top of the head HD. One luminescence target marker LTM1 is placed in the center, and four luminescence target markers LTM2, LTM3, LTM4, LTM5 are placed at equidistant all directions around it, and three luminescence target markers LTM1, LTM2, LTM3 are arranged in the first direction. Arrange it so that it is in a straight line. The three light-emitting target markers LTM1, LTM4, and LTM5 are arranged in a straight line in the second direction. The first direction is a direction orthogonal to the second direction. In addition, the heights of the three light-emitting target marks disposed in a straight line in the first direction are changed, and the heights of the three light-emitting target marks disposed in a straight line in the second direction are changed. Thereby, the rotation, height, and inclination of the bonding head can be measured.

Increasing the number of luminescence target markers or the type of distance, and using statistical calculation processing enables more accurate measurements.

(4th modified example)

16 is a diagram showing a configuration example of a light emission target marker according to a fourth modification. Fig. 17 is a diagram for explaining overlapping of adjacent circular shapes.

The luminescence target markers LTM1 to LTM5 of the third modified example are manufactured as an integral type of quartz glass QG having different thickness depending on the location, for example, holes (optical conduction paths) OC1, OC2, at positions of the luminescence target markers LTM1, LTM2, LTM3, OC3 is formed, and light is guided from light sources LS1, LS2, LS3 to holes OC1, OC2, OC3 through optical fibers OF1, OF2, OF3. Thereby, the relative position can be stabilized. In addition, by separately controlling the light emission of each light source LS1, LS2, LS3 by the power source/control unit PC1, PC2, PC3, it is turned on one by one, and the influence of the overlapping of the adjacent circular shape as shown in Fig. 17 can be prevented. The luminescence target markers LTM4 and LTM5 are similarly configured.

An example in which the above-described embodiment is applied to a die bonder will be described below.

[Example]

18 is a top view schematically showing a die bonder according to an embodiment. 19 is a view for explaining the operation of the pickup head and the bonding head when viewed from the direction of arrow A in FIG. 18.

The die bonder 10 is roughly divided into a supply unit 1 for supplying a die D mounted on a substrate S on which a product area (hereinafter referred to as a package area P) to be one or more final packages is printed, and a pickup The unit 2, the intermediate stage unit 3, the bonding unit 4, the conveying unit 5, the substrate supply unit 6, the substrate carrying unit 7 and a control unit that monitors and controls the operation of each unit It has (8). The Y-axis direction is the front-rear direction of the die bonder 10, and the X-axis direction is the left-right direction. The die supply unit 1 is disposed on the front side of the die bonder 10, and the bonding unit 4 is disposed on the rear side.

First, the die supply unit 1 supplies the die D to be mounted on the package area P of the substrate S. The die supply unit 1 has a wafer holder 12 for holding the wafer 11 and a pushing unit 13 indicated by a dotted line for pushing up the die D from the wafer 11. The die supply unit 1 moves in the XY direction by a driving means (not shown), and moves the pick-up die D to the position of the pushing unit 13.

The pickup unit 2 lifts, rotates, and moves the pickup head 21 for picking up the die D, the Y driving unit 23 of the pickup head for moving the pickup head 21 in the Y direction, and the collet 22. Each drive unit (not shown) that moves in the direction is provided. The pickup head 21 has a collet 22 (refer to FIG. 19) that adsorbs and holds the pushed die D at its tip, picks up the die D from the die supply unit 1, and transfers it to the intermediate stage 31. To load. The pickup head 21 has respective driving units (not shown) for lifting, rotating, and moving the collet 22 in the X direction.

The intermediate stage portion 3 has an intermediate stage 31 for temporarily loading the die D, and a stage recognition camera 32 for recognizing the die D on the intermediate stage 31.

The bonding unit 4 picks up the die D from the intermediate stage 31 and bonds it on the package area P of the substrate S to be conveyed, or laminates it on the die bonded on the package area P of the substrate S. Bonded in the form. The bonding unit 4 includes a bonding head 41 including a collet 42 (see Fig. 19) that sucks and holds the die D at the tip end, similarly to the pickup head 21, and the bonding head 41 is Y A Y driving unit 43 that moves in the direction and a substrate recognition camera 44 that captures a position recognition mark (not shown) of the package area P of the substrate S and recognizes a bonding position. Here, the bonding head 41 corresponds to the bonding head HD of the embodiment, and is provided with a light emission target marker LTM of the embodiment and any one of the first to third modifications on the upper portion thereof.

With this configuration, the bonding head 41 corrects the pickup position and posture based on the image pickup data of the stage recognition camera 32, picks up the die D from the intermediate stage 31, and the substrate recognition camera 44 Bond the die D to the substrate based on the imaging data of.

The conveyance part 5 has a substrate conveyance claw 51 which grasps and conveys the board|substrate S, and the conveyance lane 52 through which the board|substrate S moves. The board|substrate S moves by driving a nut (not shown) of the board|substrate transfer claw 51 provided in the transfer lane 52 with a ball screw (not shown) provided along the transfer lane 52.

With such a configuration, the substrate S moves from the substrate supply unit 6 along the transfer lane 52 to the bonding position, and after bonding, moves to the substrate unloading portion 7 to transfer the substrate to the substrate unloading portion 7. Hand S.

The control unit 8 includes a memory storing a program (software) that monitors and controls the operation of each unit of the die bonder 10, and a central processing unit (CPU) that executes a program stored in the memory.

Next, the configuration of the die supply unit 1 will be described with reference to FIGS. 20 and 21. 20 is a diagram showing an external perspective view of a die supply unit. 21 is a schematic cross-sectional view showing a main part of a die supply unit.

The die supply unit 1 includes a wafer holding stand 12 that moves in the horizontal direction (XY direction) and a push-up unit 13 that moves in the vertical direction. The wafer holder 12 horizontally holds an expand ring 15 for holding the wafer ring 14 and a dicing tape 16 that is held on the wafer ring 14 and adhered to a plurality of dies D. It has a locating support ring 17. The pushing unit 13 is disposed inside the support ring 17.

The die supply unit 1 lowers the expand ring 15 holding the wafer ring 14 when the die D is pushed up. As a result, the dicing tape 16 held on the wafer ring 14 is stretched, the gap between the die D is enlarged, and the die D is pushed up from the lower side of the die D by the pushing unit 13, The pickup property of D is improved. In addition, the adhesive that adheres the die to the substrate along with the thinning is a film-like adhesive material called a die attach film (DAF) 18 between the wafer 11 and the dicing tape 16 from liquid to film. Is gluing. In the wafer 11 having the die attach film 18, dicing is performed with respect to the wafer 11 and the die attach film 18. Therefore, in the peeling process, the wafer 11 and the die attach film 18 are peeled from the dicing tape 16.

The die bonder 10 includes a wafer recognition camera 24 for recognizing the posture of the die D on the wafer 11, a stage recognition camera 32 for recognizing the posture of the die D mounted on the intermediate stage 31, It has a substrate recognition camera 44 that recognizes the mounting position on the bonding stage BS. It is the stage recognition camera 32 that is involved in pickup by the bonding head 41 and the substrate recognition camera 44 that is involved in bonding to the mounting position by the bonding head 41 that must correct the posture shift between the recognition cameras. to be.

The control unit 8 will be described with reference to FIG. 22. 22 is a block diagram showing a schematic configuration of a control system. The control system 80 includes a control unit 8, a driving unit 86, a signal unit 87, and an optical system 88. The control unit 8 is roughly divided into a control/operation unit 81 mainly including a CPU (Central Processor Unit), a storage unit 82, an input/output unit 83, a bus line 84, and a power supply unit ( 85). The storage device 82 includes a main memory device 82a including a RAM storing processing programs, etc., and an auxiliary storage device including an HDD, SSD, etc. storing control data or image data necessary for control. Has (82b). The input/output device 83 includes a monitor 83a for displaying device status and information, a touch panel 83b for inputting an operator's instruction, a mouse 83c for operating the monitor, and an optical system 88. It has an image introducing device 83d for introducing image data. Further, the input/output device 83 includes a motor control device 83e that controls a driving unit 86 such as an XY table (not shown) of the die supply unit 1 or a ZY drive shaft of the bonding head table, and various sensor signals or It has an I/O signal control device 83f for introducing or controlling a signal from a signal unit 87 such as a switch such as a lighting device. The optical system 88 includes a wafer recognition camera 24, a stage recognition camera 32, and a substrate recognition camera 44. The control/calculation device 81 introduces and calculates necessary data via the bus line 84, and sends information to the control of the pickup head 21 or the like, the monitor 83a, and the like.

The control unit 8 stores the image data captured by the wafer recognition camera 24, the stage recognition camera 32, and the substrate recognition camera 44 through the image introduction device 83d in the storage device 82. Using the software programmed based on the saved image data, the position of the package area P of the die D and the substrate S and the surface inspection of the die D and the substrate S are performed using the control/calculation device 81. Based on the position of the package area P of the die D and the board|substrate S calculated by the control/calculation device 81, the drive part 86 is made to move through the motor control device 83e by software. By this process, the die on the wafer is positioned, and the die D is bonded onto the package area P of the substrate S by operating by the driving unit of the pickup unit 2 and the bonding unit 4. The wafer recognition camera 24, the stage recognition camera 32, and the substrate recognition camera 44 to be used are gray scale, color, etc., and digitize light intensity.

23 is a flowchart illustrating a die bonding process in the die bonder of FIG. 18.

In the die bonding process of the embodiment, first, the control unit 8 takes out the wafer ring 14 holding the wafer 11 from the wafer cassette and mounts it on the wafer holder 12, and the wafer holder 12 ) Is conveyed to the reference position where the die D is picked up (wafer loading (step P1)). Subsequently, from the image acquired by the wafer recognition camera 24, the control part 8 performs fine adjustment so that the arrangement|positioning position of the wafer 11 may correspond exactly with the reference position.

Next, the control unit 8 pitches the wafer holder 12 on which the wafer 11 is mounted and holds it horizontally, thereby placing the die D first picked up in the pickup position (die transfer). (Step P2)). The wafer 11 is previously inspected for each die by an inspection device such as a prober, map data indicating good and bad for each die is generated, and stored in the storage device 82 of the control unit 8. The determination of whether the die D to be picked up is a good product or a defective product is made based on the map data. When the die D is a defective product, the control unit 8 pitches the wafer holding base 12 on which the wafer 11 is mounted at a predetermined pitch, and arranges the die D to be picked up at the pickup position. Die D is skipped.

The control unit 8 captures the main surface (top surface) of the die D as a pickup target by the wafer recognition camera 24, and calculates the amount of positional shift of the die D as the pickup target from the pickup position from the acquired image. The control unit 8 moves the wafer holder 12 on which the wafer 11 is mounted based on the amount of position shift, and accurately places the die D as a pickup target at the pickup position (die positioning (step P3)). .

Next, the control unit 8 performs a surface inspection of the die D from the image acquired by the wafer recognition camera 24 (step P4). Here, the control unit 8 determines whether there is a problem in the surface inspection, and when it is determined that there is no problem on the surface of the die D, proceeds to the next step (step P9 to be described later), but when it is determined that there is a problem, The surface image is visually confirmed, or inspection with higher sensitivity or by changing lighting conditions, etc. is performed. If there is a problem, a skip treatment is performed, and if there is no problem, the next step is performed. In the skip process, the process P9 and after of the die D is skipped, the wafer holder 12 on which the wafer 11 is mounted is pitch-moved at a predetermined pitch, and the die D to be picked up next is placed at the pickup position.

The control unit 8 loads the substrate S into the transfer lane 52 from the substrate supply unit 6 (substrate loading (step P5)). The control part 8 moves the board|substrate conveyance claw 51 which grasps and conveys the board|substrate S to a bonding position (substrate conveyance (process P6)).

The substrate recognition camera 44 captures an image of the position recognition mark (not shown) of the package area P of the substrate S, recognizes the bonding position, and performs positioning (substrate positioning (step P7)).

Next, the control unit 8 performs a surface inspection of the package area P of the substrate S from the image acquired by the substrate recognition camera 44 (step P8). Here, the control unit 8 determines whether there is a problem in the surface inspection, and if it is determined that there is no problem with the surface of the package area P of the substrate S, the process proceeds to the next step (step P9 to be described later). In the case of determination, a surface image is visually confirmed, or a higher-sensitivity inspection or an inspection in which lighting conditions are changed, etc. are performed. If there is a problem, a skip treatment is performed, and if there is no problem, the next step is performed. In the skip process, the step P10 and later to the tab of the package area P of the substrate S are skipped, and defect registration is performed in the substrate start information.

The control unit 8 arranges the die D as a pickup target at the pickup position accurately by the die supply unit 1, and then transfers the die D from the dicing tape 16 by the pickup head 21 including the collet 22. It picks up (die handling (process P9)), and loads it on the intermediate stage 31 ((process P10). The control part 8 detects the posture deviation (rotational deviation) of the die loaded on the intermediate stage 31. The die D is imaged by the stage recognition camera 32 (step P11). When there is a shift in posture, the control unit 8 uses a turning drive device (not shown) installed in the intermediate stage 31 to mount the position. The posture shift is corrected by turning the stage 31 on a surface parallel to the mounting surface having a.

The control unit 8 performs a surface inspection of the die D from the image acquired by the stage recognition camera 32 (step P12). Here, the control unit 8 determines whether there is a problem in the surface inspection, and when it is determined that there is no problem on the surface of the die D, proceeds to the next step (step P13 to be described later), but when it is determined that there is a problem, , Check the surface image visually, or perform a more sensitive inspection or inspection with changing lighting conditions, etc., if there is a problem, the die is loaded into a defective product tray (not shown) and skipped, if there is no problem Then, the following process is performed. In the skip process, the process P13 and after of the die D is skipped, the wafer holding base 12 on which the wafer 11 is mounted is pitch-moved at a predetermined pitch, and the die D to be picked up next is placed at the pickup position.

The control unit 8 picks up the die D from the intermediate stage 31 by the bonding head 41 including the collet 42, and is bonded to the package area P of the substrate S or the package area P of the substrate S. Die bonding to the die (die attach (step P13)). The control unit 8 captures the light-emitting target marker mounted on the upper portion of the bonding head 41 with the substrate recognition camera 44, recognizes the position and posture of the bonding head 41, and detects the position and posture of the bonding head 41. In this case, correction is performed.

After bonding the die D, the control unit 8 inspects the die D and the substrate S by imaging the die D and the substrate S with the substrate recognition camera 44 to determine whether the bonding position is correct (inspecting the relative position of the die and the substrate (step P14)). . At this time, the center of the die and the center of the tab are obtained, similar to the alignment of the die, and the relative position is checked.

Next, the control unit 8 performs surface inspection of the die D and the substrate S from the image acquired by the substrate recognition camera 44 (step P15). Here, the control unit 8 determines whether there is a problem in the surface inspection, and when it is determined that the surface of the bonded die D has no problem, proceeds to the next step (step P9 to be described later), but determines that there is a problem. In this case, a surface image is visually confirmed, or a higher sensitivity inspection or an inspection in which lighting conditions are changed, etc. are performed, if there is a problem, a skip treatment is performed, and if there is no problem, the next step is performed. In the skip process, defect registration is performed in the substrate start-up information.

Thereafter, according to the same procedure, die D is bonded to the package area P of the substrate S one by one. When bonding of one substrate is completed, the substrate S is moved to the substrate unloading section 7 with the substrate transfer hook 51 (substrate transfer (step P16)), and the substrate S is handed over to the substrate unloading section 7 ( Unloading the substrate (step P17).

Thereafter, according to the same procedure, the die D is peeled from the dicing tape 16 one by one (step P9). When the pickup of all die D except the defective product is completed, the dicing tape 16 and the wafer ring 14, etc., which have held the die D in the outer shape of the wafer 11, are unloaded into the wafer cassette (step P18. ).

As described above, the invention made by the present inventors has been specifically described based on the embodiments, modifications and examples, but the present invention is not limited to the above embodiments, modifications and examples, and it goes without saying that various modifications are possible. .

For example, in the embodiment, the die appearance inspection recognition is performed after the die position recognition, but the die position recognition may be performed after the die appearance inspection recognition.

Further, in the embodiment, the DAF is adhered to the back surface of the wafer, but the DAF may not be present.

Further, in the embodiment, one pickup head and one bonding head are each provided, but two or more may be used respectively. In addition, although the intermediate stage is provided in the embodiment, the intermediate stage may not be present. In this case, the pickup head and the bonding head may be used both.

Further, in the embodiment, the die is bonded with the surface up, but after picking up the die, the front and back of the die may be inverted and the back of the die may be bonded upward. In this case, the intermediate stage need not be provided. This device is called a flip chip bonder.

10: die bonder
1: die supply
13: push-up unit
2: pickup unit
24: wafer recognition camera
3: middle stage part
31: middle stage
32: stage recognition camera
4: bonding part
41: bonding head
42: collet
44: board recognition camera
5: transfer unit
51: substrate transfer hook
8: control unit
S: substrate
BS: Bonding stage
D: Die
P: Package area
CA: Camera
HD: Bonding head
LTM: Luminous target marker

Claims (15)

A bonding head formed above the substrate and for loading the picked up die onto the substrate,
A target marker that emits light formed on the bonding head,
An imaging device formed above the bonding head and configured to image a position recognition mark and the target marker formed on the substrate;
Control device for controlling the bonding head and the imaging device
And,
In the control device, the image pickup device focuses on the position recognition mark and is larger than the light source image when the target marker is in focus at a position shorter than the focal position of the image pickup device. A die bonding apparatus configured to detect a state of the bonding head based on an image obtained by photographing a circular image to be taken. The method of claim 1,
The target marker is a die bonding device in which a light point is small. The method of claim 1,
The control device is a die bonding device that measures the position of the bonding head based on the circular shape of the target marker. The method of claim 1,
The bonding head includes a plurality of the target markers on a straight line,
The control device is a die bonding device that measures the rotation or height of the bonding head based on the circular shape of the target marker. The method of claim 3,
The bonding head includes a plurality of the target markers on a straight line,
The control device is a die bonding device that measures the rotation or height of the bonding head based on the circular shape of the target marker. The method of claim 1,
The heights of the plurality of target markers are different,
The control device is a die bonding device that measures a tilt or a direction of the tilt of the bonding head based on the circular shape of the target marker. The method of claim 3,
The heights of the plurality of target markers are different,
The control device is a die bonding device that measures a tilt or a direction of the tilt of the bonding head based on the circular shape of the target marker. The method of claim 4,
The heights of the plurality of target markers are different,
The control device is a die bonding device that measures a tilt or a direction of the tilt of the bonding head based on the circular shape of the target marker. The method according to any one of claims 1 to 8,
The light source of the target marker is positioned apart from the bonding head, and the target marker and the light source are connected by an optical fiber. The method according to any one of claims 1 to 8,
A pickup head for picking up the die,
Further comprising an intermediate stage on which the picked up die is loaded,
The bonding head is a die bonding apparatus for picking up the die mounted on the intermediate stage. (a) A bonding head formed above the substrate with a target marker emitting light thereon, and a position recognition mark formed on the substrate and the target marker formed above the bonding head. A step of preparing a die bonding device having the device, and
(b) carrying in the wafer ring holder holding the dicing tape to which the die is attached, and
(c) the step of carrying in the substrate, and
(d) a step of picking up the die,
(e) bonding the picked-up die onto the substrate or a die already bonded to the substrate
And,
In the step (e), the imaging device is obtained by imaging a circular image that is larger than the light source image when the target marker is in focus in a state that is out of focus at a position shorter than the focal position of the imaging device. A method of manufacturing a semiconductor device for detecting a state of the bonding head based on an image. The method of claim 11,
The method of manufacturing a semiconductor device in which the target marker is an LED having a small light point. The method of claim 11,
In the step (e), the position of the bonding head is measured based on the circular image of the target marker. The method of claim 13,
The bonding head includes a plurality of the target markers on a straight line,
In the step (e), the rotation or height of the bonding head is measured based on the circular shape of the target marker. The method of claim 14,
The heights of the plurality of target markers are different,
In the step (e), the inclination of the bonding head is measured based on the circular image of the target marker.

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