TW202503940A - Semiconductor manufacturing device, inspection device, and semiconductor device manufacturing method - Google Patents

Abstract

To provide a technique capable of detecting a state of a bonded die. A semiconductor manufacturing device includes: a stage that holds a substrate to which a die is bonded with a bond head; a recognition camera provided above the substrate; an illumination device provided above the substrate; and a control device configured to irradiate the die with illumination light by the illumination device and photograph the die by the recognition camera, and inspect a state of the die on the basis of the presence or absence of a mirror image of the illumination light, or a position of the mirror image of the illumination light or a shape of the mirror image of the illumination light, or a brightness distribution of the mirror image of the illumination light.

Description

Semiconductor manufacturing device, inspection device, and semiconductor device manufacturing method

The present invention relates to a semiconductor manufacturing device, for example, a die bonding machine that can be used to inspect the bonding state of a die.

As one of the manufacturing processes of semiconductor devices, there is a die bonding process, which uses a collet (adsorption nozzle) provided on a bonding head to pick up a die, and the picked-up die is bonded to a substrate or a die already mounted on a substrate. [Prior art literature] [Patent literature]

[Patent Document 1] Japanese Patent Application Publication No. 2022-150045

(The problem that the invention is trying to solve)

There are cases where the crystal dies are not bonded normally. For example, there are cases where a part of the crystal dies is displaced in the vertical direction and bonded.

This case is to provide a technology that can detect the bonding state of bonded dies. Other issues and novel features can be clearly known from the description and attached figures of this manual. (Means for solving the problem)

The representative of this case is briefly described as follows. That is, a semiconductor manufacturing device is provided with: a platform that holds a substrate to which a die is bonded by a bonding head; an identification camera that is disposed above the substrate; an illumination device that is disposed above the substrate; and a control device that is configured to irradiate the die with illumination light by the illumination device and to photograph the die by the identification camera, and to inspect the bonding state of the die based on the presence or absence of a mirror image of the illumination light, the position of the mirror image of the illumination light, the shape of the mirror image of the illumination light, or the distribution of the brightness of the mirror image of the illumination light. [Effect of the invention]

According to this case, the bonding state of the bonded dies can be detected.

The following drawings are used to illustrate the embodiments and variations. However, in the following description, the same components are given the same symbols and repeated descriptions are omitted. In addition, in order to make the description clearer, the drawings schematically show the width, thickness, shape, etc. of each part compared to the actual form, but this is ultimately an example and does not limit the present case.

The structure of a die bonding machine as one form of semiconductor manufacturing equipment is described using FIGS. 1 to 3. FIG. 1 is a top view schematically showing a die bonding machine of an implementation form. FIG. 2 is a view schematically showing the structure when viewed from the direction of arrow A in FIG. 1. FIG. 3 is a side view schematically showing a preform portion shown in FIG. 1.

The die bonding machine 1 generally comprises a wafer supply unit 10, a pickup unit 20, an intermediate platform unit 30, a preforming unit 90, a bonding unit 40, a conveying unit 50, a substrate supply unit 60, a substrate unloading unit 70 and a control unit (control device, controller) 80. The Y2-Y1 direction is the front-back direction of the die bonding machine 1, the X2-X1 direction is the left-right direction, and the Z1-Z2 direction is the up-down direction. The wafer supply unit 10 is arranged at the front side of the die bonding machine 1, and the bonding unit 40 is arranged at the rear side.

The wafer supply unit 10 includes a wafer cassette elevator 11 , a wafer holding table 12 , a peeling unit 13 , and a wafer recognition camera 14 .

The wafer box elevator 11 moves a wafer box (not shown) containing a plurality of wafer rings WR up and down to a wafer transfer height. The wafer rings WR supplied from the wafer box elevator 11 are aligned by a wafer correction slide (not shown). The wafer rings WR are taken out from the wafer box and supplied to the wafer holding table 12 by a wafer picker (not shown), or taken out from the wafer holding table 12 and stored in the wafer box.

The wafer W is adhered (attached) to the dicing tape DT, and the wafer W is divided into a plurality of dies D. The dicing tape DT is held on the wafer ring WR. The wafer W is, for example, a semiconductor wafer or a glass wafer, and the dies D are semiconductor chips or glass chips, or MEMS (Micro Electro Mechanical Systems).

The wafer holding table 12 is moved in the X1-X2 direction and the Y1-Y2 direction by the unillustrated XY table and the driving part, so that the picked-up die D is moved to the position of the peeling unit 13. The wafer holding table 12 is rotated by the unillustrated driving part in the XY plane by the wafer ring WR. The peeling unit 13 is moved in the Z1-Z2 direction by the unillustrated driving part. The peeling unit 13 peels the die D from the dicing tape DT.

The wafer recognition camera 14 is used to grasp the pick-up position of the die D picked up from the wafer W or to inspect the surface of the die D.

The pickup unit 20 includes a pickup head 21 and a Y drive unit 23. The pickup head 21 is provided with a clamp 22 for adsorbing and holding the peeled grain D at the front end. The pickup head 21 picks up the grain D from the wafer supply unit 10 and places it on the intermediate platform 31. The Y drive unit 23 moves the pickup head 21 in the Y1-Y2 direction. The pickup unit 20 includes various drives (not shown) for lifting, rotating, and moving the pickup head 21 in the X1-X2 direction.

The intermediate stage portion 30 includes an intermediate stage 31 on which the die D is placed and a stage recognition camera 34 for recognizing the die D on the intermediate stage 31 . The intermediate stage 31 has suction holes for adsorbing the placed die D. The placed die D is temporarily held on the intermediate stage 31 .

The preforming unit 90 includes a syringe 91, a drive unit 93, a preforming camera 94 as a camera, and a preforming platform 96. The syringe 91 has a nozzle 92 at the front end of the lower portion. The syringe 91 applies paste to the substrate S transported to the preforming platform 96 by the transport unit 50. The drive unit 93 moves the syringe 91 in the X1-X2 direction, the Y1-Y2 direction, and the Z1-Z2 direction. The substrate S is, for example, a wiring substrate or a lead frame formed of a metal thin plate, a glass substrate, or the like.

The preform camera 94 is used to grasp the position of the paste applied to the substrate S by the syringe 91. The preform stage 96 rises when the paste is applied to the substrate S and supports the substrate S from below. The preform stage 96 has suction holes (not shown) for vacuum suction of the substrate S, and can fix the substrate S.

The bonding section 40 includes a bonding head 41, a Y drive section 43, a substrate identification camera 44, and a bonding platform 46. The bonding head 41 is provided with a clamp 42 for adsorbing and holding the die D at the front end. The Y drive section 43 moves the bonding head 41 in the Y1-Y2 direction. The substrate identification camera 44 photographs the position identification mark (not shown) of the packaging area P of the substrate S to identify the bonding position. Here, a plurality of product areas (hereinafter referred to as packaging areas P) that eventually become a package are formed on the substrate S. The position identification mark is provided for each packaging area P. The bonding platform 46 rises when the die D is placed on the substrate S and supports the substrate S from below. The bonding platform 46 has a suction port (not shown) for vacuum adsorbing the substrate S, and can fix the substrate S. The bonding platform 46 has a heating unit (not shown) for heating the substrate S. The bonding unit 40 has various driving units (not shown) for lifting, rotating, and moving the bonding head 41 in the X1-X2 direction.

With such a configuration, the bonding head 41 corrects the pickup position and posture based on the imaging data of the stage recognition camera 34, and picks up the die D from the intermediate stage 31. Then, the bonding head 41 bonds (mounts and bonds) the die D to the packaging area P coated with paste on the conveyed substrate S based on the imaging data of the substrate recognition camera 44.

The conveying section 50 includes a conveying claw 51 for grasping and conveying a substrate S and a pair of conveying paths 52 for moving the substrate S. The substrate S is moved in the X1-X2 direction by driving a nut (not shown) of the conveying claw 51 with a ball screw (not shown). The ball screw (not shown) is provided along the conveying path 52, and the driving conveying claw 51 is provided on the conveying path 52. With such a configuration, the substrate S is moved from the substrate supply section 60 along the conveying path 52 to the bonding position, and after bonding, is moved to the substrate carrying-out section 70, and the substrate S is delivered to the substrate carrying-out section 70.

The substrate supply unit 60 takes out the substrate S that has been carried in and stored in the transport jig from the transport jig, and supplies it to the transport unit 50. The substrate unloading unit 70 stores the substrate S transported by the transport unit 50 in the transport jig.

The control system of the die bonder 1 will be described using Fig. 4. Fig. 4 is a block diagram showing a schematic configuration of the control system of the die bonder shown in Fig. 1 .

The control system 8 includes a control unit 80, a drive unit 86, a signal unit 87, and an optical system 88. The control unit 80 is roughly divided into a control and calculation device 81 composed of a CPU (Central Processing Unit), a memory device 82, an input/output device 83, a bus 84, and a power supply unit 85. The memory device 82 includes a main memory device 82a and an auxiliary memory device 82b. The main memory device 82a is composed of a RAM (Random Access Memory) for storing processing programs, etc. The auxiliary memory device 82b is composed of a HDD (Hard Disk Drive) or SSD (Solid State Drive) for storing control data or image data required for control.

The input/output device 83 has: A monitor 83a for displaying the device status or information of the die bonding machine 1; A touch panel 83b for inputting the operator's instructions; A mouse 83c for operating the monitor 83a; and An image input device 83d for taking in image data from the optical system 88. The input/output device 83 further has a motor control device 83e and an I/O signal control device 83f. The motor control device 83e is a drive unit 86 that controls the XY table of the wafer supply unit 10 or the ZY drive axis of the bonding head table of the bonding unit 40. The I/O signal control device 83f takes in signals from the signal unit 87 or controls the signal unit 87. The signal unit 87 includes switches or knobs for controlling the brightness of various sensors and lighting devices. The control and calculation device 81 takes in necessary data through the bus line 84 and performs calculations to control the pickup head 21, etc., or transmit information to the monitor 83a, etc.

The control and calculation device 81 stores the image data captured by the optical system 88 in the memory device 82 via the image input device 83d. The optical system 88 includes a wafer recognition camera 14, a stage recognition camera 34, a substrate recognition camera 44, and a preform camera 94. The camera used in the optical system 88 digitizes light intensity or color. The control and calculation device 81 performs positioning of the die D and the substrate S, inspection of the coating pattern of the paste, and surface inspection of the die D and the substrate S by software programmed according to the stored image data. The control and calculation device 81 actuates the drive unit 86 via the motor control device 83e according to the calculated positions of the die D and the substrate S. Through this process, the control and operation device 81 positions the die D on the wafer W, and operates the driving parts of the wafer supply part 10, the pickup part 20 and the bonding part 40 to bond the die D to the packaging area P of the substrate S.

FIG5 is used to explain a bonding process (a method for manufacturing a semiconductor device) which is one of the processes of manufacturing a semiconductor device using the die bonding machine 1. FIG5 is a flow chart showing a method for manufacturing a semiconductor device using the die bonding machine shown in FIG1. In the following description, the operations of the various components constituting the die bonding machine 1 are controlled by the control unit 80.

(Wafer loading: process S1) The wafer ring WR is supplied to the wafer box of the wafer box elevator 11. The supplied wafer ring WR is supplied to the wafer holding table 12.

(Substrate loading: Step S2) The transport jig containing the substrate S is supplied to the substrate supply unit 60. The substrate S is taken out from the transport jig in the substrate supply unit 60, and the substrate S is fixed to the transport claw 51.

(Pick up: process S3) After process S1, the wafer holding table 12 is activated to pick up the desired die D from the dicing tape DT. The die D is photographed by the wafer recognition camera 14, and the positioning and surface inspection of the die D are performed based on the image data obtained by the photography. The image data is processed by the image processing, and the deviation amount (X, Y, θ direction) of the die D on the wafer holding table 12 from the die position reference point of the die bonding machine is calculated for positioning. In addition, the die position reference point is pre-set at the predetermined position of the wafer holding table 12 as the initial setting of the device. The surface inspection of the die D is performed by the image processing of the image data.

The positioned die D is peeled off from the dicing tape DT by the peeling unit 13 and the pickup head 21. The die D peeled off from the dicing tape DT is held by the chuck 22 provided in the pickup head 21 and is transported to the intermediate stage 31 for placement.

The die D on the intermediate stage 31 is photographed by the stage recognition camera 34, and the positioning and surface inspection of the die D are performed based on the image data obtained by the photography. The image data is processed by the image processing, and the deviation amount (X, Y, θ direction) of the die D on the intermediate stage 31 from the die position reference point of the die bonding machine 1 is calculated to perform positioning. In addition, the die position reference point is pre-set at the predetermined position of the intermediate stage 31 as the initial setting of the device. The surface inspection of the die D is performed by the image processing of the image data.

After transferring the die D to the intermediate platform 31, the pickup head 21 returns to the wafer supply unit 10. According to the above procedure, the next die D is peeled off from the dicing tape DT, and the same procedure is followed to peel the die D off from the dicing tape DT one by one.

(Preforming: Step S4) After Step S2, the substrate S is conveyed to the preforming platform 96 by the conveying unit 50. The surface of the substrate S before coating is photographed by the preforming camera 94, and the surface to be coated with the paste is confirmed based on the image data obtained by the photography. If there is no problem on the surface to be coated, the position of the substrate S supported by the preforming platform 96 to be coated with the paste is confirmed and positioned. Positioning is performed by pattern matching, etc.

The paste is ejected from the nozzle 92 at the front end of the syringe 91 and applied to the substrate S along the trajectory of the nozzle 92. When the paste stored in the syringe 91 is applied to the substrate S, for example, a pressurized gas such as air is supplied from the upper part of the syringe 91 for a certain period of time from a dispenser of an air pulse method, and a predetermined amount of paste is ejected. When the nozzle 92 is close to the substrate S, the syringe 91 performs a two-dimensional single-stroke scan (drawing action) in the XY plane.

The applied paste is photographed by the pre-molding camera 94. Whether the paste is correctly applied is confirmed based on the image obtained by the photography, and the applied paste is inspected (appearance inspection). That is, in the appearance inspection, it is confirmed whether the applied paste is applied in a predetermined shape and only in a predetermined amount at a predetermined position on the substrate S. The inspection content includes, for example, the presence or absence of paste, the coating area, the coating shape (excess/insufficient, protrusion), etc. In addition to the method of calculating the number of pixels after separating the area of the paste by binarization processing, the inspection can also be performed by comparison based on differences, comparison based on the score of pattern matching, etc.

(Bonding: Step S5) If there are no problems with coating, the substrate S is transported to the bonding platform 46 by the transport unit 50. The substrate S placed on the bonding platform 46 is photographed by the substrate recognition camera 44, and image data is obtained by photography. The image data is processed by image processing to calculate the deviation of the substrate S from the substrate position reference point of the die bonding machine (in the X, Y, and θ directions). In addition, the substrate position reference point is maintained in advance at the predetermined position of the bonding unit 40 as the initial setting of the device.

The absorption position of the bonding head 41 is corrected by the deviation amount of the die D on the intermediate stage 31 calculated in step S3, and the die D is absorbed by the chuck 42. The die D is bonded to a predetermined position of the substrate S supported by the bonding stage 46 by the bonding head 41 after absorbing the die D from the intermediate stage 31. The die D bonded to the substrate S is photographed by the substrate recognition camera 44, and the image data obtained by the photography is used to check whether the die D is bonded to the desired position.

After bonding the die D to the substrate S, the bonding head 41 returns to the intermediate platform 31. According to the above procedure, the next die D is picked up from the intermediate platform 31 and bonded to the substrate S. This process is repeated to bond the die D to all the packaging areas P of the substrate S.

(Substrate unloading: Step S6) The substrate S with the die D bonded thereto is transported to the substrate unloading unit 70. In the substrate unloading unit 70, the substrate S is taken out from the transport claw 51 and placed in a transport jig. The transport jig containing the substrate S is unloaded from the die bonding machine 1.

As described above, the die D is mounted on the substrate S and is carried out from the die bonding machine 1. Then, for example, the transport jig containing the substrate S with the die D mounted thereon is transported to a wire bonding process, where the electrode of the die D is electrically connected to the electrode of the substrate S via an Au wire or the like. Then, the substrate S is transported to a molding process, where the die D and the Au wire are sealed with a molding resin (not shown), thereby completing semiconductor packaging.

The stacking bonding is continued with the wire bonding process, and the transport jig carrying the substrate S with the die D mounted thereon is transported to the die bonding machine to stack the die D on the die D mounted on the substrate S. After being taken out of the die bonding machine, the die D is electrically connected to the electrode of the substrate S via the Au wire in the wire bonding process. The die D above the second section is peeled off from the dicing tape DT in the above-mentioned method, and then transported to the bonding section to be stacked on the die D. After the above-mentioned process is repeated a predetermined number of times, the substrate S is transported to the molding process to seal the plurality of die D and Au wires with a molding resin (not shown) to complete the stacking package.

The following describes an overview of a tilt inspection method for inspecting the tilt of a die D, that is, whether the die D bonded to a substrate S or the die D bonded to a semiconductor chip mounted on the substrate S is parallel to the top surface of the substrate S.

The surface of most crystal grains has the characteristic of mirror reflection. For example, the surface of crystal grain D of semiconductor wafers, glass and MEMS has the characteristic of mirror reflection. This embodiment uses an illumination device (light source) to illuminate the crystal grain and uses a recognition camera to photograph the crystal grain at the same time, and inspects the inclination of the crystal grain based on the mirror image of the irradiated light.

The tilt inspection performed by the optical system of the bonding part 40 will be described with reference to Fig. 6. Fig. 6 is a diagram showing the optical system, the die, and the image of the bonding part shown in Fig. 1 .

As shown in FIG6 , the substrate recognition camera 44 includes a camera body unit 44a and a lens unit 44b. The substrate recognition camera 44 is arranged above the substrate S in such a manner that its optical axis is perpendicular to the substrate S. The lighting device 45 is arranged above the substrate S (for example, near the substrate recognition camera 44). The lighting device 45 is composed of a ring lighting device and is arranged around the lens unit 44b. The substrate recognition camera 44 is arranged near directly above the grain D. That is, the grain D will be arranged near the center of the imaging range IR (field of view) of the substrate recognition camera 41. The control unit 80 irradiates the die D with an annular illumination light from the illumination device 45 and photographs the die D with the substrate recognition camera 44 .

As shown in NTL of FIG6 , when the die D is bonded to the substrate S horizontally (perpendicular to the optical axis), the substrate recognition camera cannot recognize the illumination (mirror image MI) incident on the die D. That is, there is no locally bright spot in the image of the die D.

As shown in TLT of FIG6 , if the crystal grain D is tilted from the horizontal, the mirror image MI of the illumination light will shine on the surface of the crystal grain D. In the image of the crystal grain D, there is a mirror image MI of a locally bright area. Here, the crystal grain D is an example of showing that the angle C1 is tilted more than the angle C3. The X1 side and the Y2 side of the image of the crystal grain D are the angle C1, and the X2 side and the Y1 side correspond to the angle C3.

The control unit 80 processes the image of the grain D and determines the tilt of the grain D based on the presence or absence of the mirror image MI. The radius of the ring of the lighting device 45 is set to a radius where the tilt angle of the grain D becomes a problem. In other words, the critical value of the tilt determination can be set by the radius of the ring lighting device. The control unit 80 can also detect the tilt direction of the grain D from the direction of the arc of the mirror image MI.

As shown in ML of FIG6 , the lighting device 45 can also be configured by setting multiple ring lighting devices in a concentric circle. The control unit 80 sequentially lights the ring lighting devices from the inside and takes in images at each lighting time. By confirming the mirror image MI reflected in the multiple images, in addition to the presence or absence and direction of the tilt of the grain D, the tilt amount (tilt angle) of the grain D can also be grasped. That is, by determining the position of the mirror image MI on the surface of the grain D by image processing, the tilt amount can be grasped. By selecting the ring lighting to be lit, the critical value of the tilt amount can also be adjusted.

The control unit 80 can also adjust the coating amount by the tilt amount or direction (the tilt direction of the die). For example, the control unit 80 adjusts the coating amount by changing the movement speed of the head of only a certain track of the penlite coating or changing the coating pressure and speed of the dispenser. In this way, the tilt amount of the die D can be reduced. The coating amount can also be adjusted by automatic feedback during production.

The control unit 80 detects the tilt, and when the tilt is judged to be above a critical value, an error may be reported, or the defect of the die may be recorded. When the control unit 80 judges that the tilt is above a critical value, the bonding head 41 may be used to re-press the die D to reduce the tilt. In this case, the tilt may be re-checked.

When the registration is bad, the control unit 80 may not bond the stacked and bonded product to the subsequent layers, or may bond dummy die. By bonding dummy die, the primary molding in the molding process can be stabilized.

According to this implementation form, one or more of the following effects can be achieved.

(a) The tilt can be checked during the die bonding process, and quality control for defects caused by the presence or absence of the tilt is possible. This can improve defects caused by the presence or absence of the tilt of the die.

For example, an image sensor chip having a semiconductor chip is mounted on a substrate S, a paste is framed on the image sensor chip, and a crystal grain D of a glass chip (cover glass) is mounted thereon. The crystal grain D is slightly raised with respect to the upper surface of the substrate S (the upper surface of the semiconductor chip). At this time, it is required that the crystal grain D does not tilt with respect to the upper surface of the substrate S. That is, it is necessary to confirm whether the crystal grain D is tilted, and this can be confirmed by this embodiment.

(b) Since a displacement meter using a laser or the like can only inspect one point at a time, multiple points must be measured to find out the tilt amount. This takes up processing time. In this embodiment, the tilt of the entire grain can be grasped in one image capture. This allows for faster inspection than tilt inspection using a displacement meter, and can maintain and improve production efficiency.

(c) Compared with the case of measuring the inclination of the grains by a displacement meter, the system can be simplified and the maintainability can be improved.

<Variations> Below, several examples are given to show representative variations of the implementation. In the following description of the variations, the same symbols as those in the above-mentioned implementation can be used for parts having the same structure and function as those in the above-mentioned implementation. Moreover, the description of the part can be appropriately cited from the description of the above-mentioned implementation within the scope of technical non-contradiction. In addition, part of the above-mentioned implementation and all or part of the multiple variations can be appropriately and complexly applied within the scope of technical non-contradiction.

(First variant) The tilt inspection of the first variant is described using FIG. 7. FIG. 7 is a diagram showing the optical system, crystal grains, and images of the first variant.

The lighting device 45 of the first modification is a circular lighting device disposed near the lens unit 44b. The circular lighting device is a circular light source or a point light source with a clear outline. This light source does not need to be parallel light, and may be diffuse light.

As shown in NTL of FIG. 7 , the die D is disposed at a position away from the center of the imaging range (field of view) IR of the substrate recognition camera 44 , so that when the die D is held horizontally, the mirror image of the illumination light shines on the center of the die D.

As shown in NTL of FIG. 7 , when the chip D is horizontally bonded to the substrate S or the like, the mirror image MI of the illumination light is illuminated in the center of the chip D in a circular shape.

As shown in TLT of FIG7 , if the grain D is tilted from the horizontal, the mirror image MI of the illumination light will not be illuminated in a circular shape at the center of the grain D. Here, the grain D is an example showing that the angle C1 is tilted more than the angle C3. The X1 side and the Y2 side of the image of the grain D are the angle C1, and the X2 side and the Y1 side correspond to the angle C3. The mirror image MI is slightly illuminated near the angle C1 of the grain D. If the tilt of the grain D is greater, the mirror image MI is not illuminated.

The control unit 80 processes the image of the grain D and determines the inclination of the grain D according to the presence and position of the mirror image MI. If the mirror image MI is captured at the correct position on the surface of the grain D, it is determined that there is no inclination of the grain D and it is correctly bonded. If the position of the mirror image MI is deviated or not captured, it is determined that there is inclination of the grain D. By this method, the inclination of the grain D is inspected to determine whether it is a good product or a defective product. The control unit 80 can also detect the inclination direction of the grain D from the position of the mirror image MI.

As shown in ML of FIG. 7 , the lighting device 45 can also be constructed by setting multiple ring lightings in a concentric circle with a circular lighting device as the center. The control unit 80 sequentially lights up the lighting and takes in images at each lighting time. By confirming the mirror image MI reflected in multiple images, not only the presence or absence of the tilt of the grain D but also the tilt amount of the grain D can be grasped. That is, by determining the position of the mirror image MI on the surface of the grain D by image processing, the tilt amount or direction can be grasped. It is also possible to adjust the diameter of the circular light-emitting area by the combination of the lightings that are lit, thereby adjusting the detection threshold value of the tilt amount.

Through the above-mentioned structure and operation, the first variant can achieve the same effect as the implementation form.

(Second modification) The inspection for detecting the warp of a grain is described using FIG8. FIG8 is a diagram showing the optical system, a grain, and its image in the second modification. FIG9 is a diagram showing a method for moving the mirror position.

In the optical system of the embodiment and the first modification, an example of inspecting the inclination of the grain is described. On the other hand, in the optical system of the second modification, the warp of the grain is inspected.

The stacking of the grains is performed in a staggered manner so that the bonding pads of the grains are not covered by the grains on the upper layer. In other words, the grains on the lower layer are not in contact with the bonding pads on the opposite side of the grains on the upper layer. That is, the stacked grains have a hollow area at the bottom. There is a warping inclination on the side of the hollow area.

As shown in FIG. 8 , an illumination device 45 formed of a stripe-shaped illumination device is provided on the side ( X1 side) opposite to the position ( X2 side) where the warp of the die D is expected to occur with respect to the center of the lens unit 44 b .

As shown in NCR of FIG8 , when there is no or little warping of the grain D, the mirror image MI of the illumination light of the illumination device 45 will not be irradiated into the grain D. That is, there is no locally bright spot in the image of the grain D.

As shown in CRV of FIG. 8 , if the grain D is warped, the mirror image MI of the illumination light will be incident on the warped portion.

The control unit 80 performs image processing on the image of the grain D, and determines the presence and degree of the warp of the grain D by the presence or absence of the mirror image MI.

As shown in ML of Fig. 8, the lighting device 45 may be a strip lighting device arranged in multiple rows. In this way, the position of the mirror image MI can be moved. The control unit 80 may also light up a plurality of strip lighting devices in sequence, and calculate the warp amount from the position of the mirror image MI by taking in and processing the image each time.

In addition, instead of the lighting device 45 being composed of a plurality of strip lighting devices, as shown in LM of FIG. 9 , the lighting device 45 composed of a single strip lighting device can be moved in the X1-X2 direction, or as shown in CM of FIG. 9 , the substrate recognition camera 44 can be moved in the X1-X2 direction, or as shown in DM of FIG. 9 , the chip D (substrate S) can be moved in the X1-X2 direction.

In the second modification, the bend of the die D can be inspected in the die bonding process, and quality control regarding defects caused by the presence or absence of bend is possible. Thereby, defects caused by the presence or absence of bend of the die can be improved.

(Third variant) FIG. 10 is a diagram showing the configuration of the strip lighting device of the third variant. In the second variant, an example is described in which the lighting device 45 composed of the strip lighting device is configured in one direction based on the substrate recognition camera 44. In contrast, in the third variant, the lighting device 45 is configured in multiple directions based on the substrate recognition camera 44.

As shown in 4DL of FIG. 10 , the lighting device 45 composed of strip lighting devices can be set in four directions (X1 side, X2 side, Y1 side, and Y2 side) with the substrate recognition camera 44 as the center. In this way, even if the die D is staggered in any of the four directions to form a stack, the presence or absence of warp can be determined. Instead of setting the lighting device 45 in multiple directions, as shown in 1L4D of FIG. 10 , one lighting device 45 can be moved in four directions.

In addition, when the mirror image MI of the illumination light from the illumination device 45 (which is arranged on the side of the hollow region formed by the stacked crystal grains (for example, the X2 side)) is illuminated, the droop of the side of the hollow region can also be grasped. In addition, in this case, the warp is determined based on the mirror image MI of the illumination light from the illumination device 45 which is arranged on the X1 side. As shown in 2DL of FIG. 10, even if the illumination device 45 is arranged in two directions, the warp and droop of the crystal grain D can be inspected. Instead of arranging the illumination device 45 in two directions, one illumination device 45 can be moved in two directions as shown in 1L2D of FIG. 10.

(Fourth variant) The optical system of the fourth variant is described using FIG. 11. FIG. 11 is a diagram showing the optical system of the fourth variant, a crystal grain D, and its image.

The lighting device 45 of the fourth modification is constituted by a lens-inserted coaxial lighting device in the camera body unit 44a.

When the lens built into the lens insertion type coaxial illumination device is a telecentric lens, the lens insertion type coaxial illumination device reflects the light from the light source 45a with the internal half mirror and irradiates the crystal grain D with parallel light.

As shown in NTL of FIG. 11 , when the level of the grain D is kept very accurately, the entire grain D reflects light, and the mirror image MI of the illumination light is irradiated into the entire grain D.

As shown in TLT of FIG. 11 , when the die is slightly tilted, light is not reflected and the mirror image MI of the illumination light does not enter the die D.

The control unit 80 performs image processing on the image of the grain D and determines the tilt of the grain D according to the overall brightness of the grain D. By selecting the diameter of the point light source 45a, the critical value of the tilt determination can be adjusted.

Aperture may be provided in the lens of the illumination device 45 or the light source 45a. In this way, the parallelism of the illumination light of the parallel light can be adjusted. By adjusting the parallelism, as shown in DFL of FIG. 11, when the grain D has a bend DF, a small (dark) area appears in the image of the grain D. Therefore, a slight bend can be detected.

When the lens used in the illumination device 45 is a non-telecentric lens, the mirror image MI on the surface of the grain D forms a blurred circular shape. The control unit 80 performs image processing on the image of the grain D, and determines whether the grain D is tilted based on the presence or absence of the circular mirror image MI.

(Fifth variant) The optical system of the fifth variant is described using FIG. 12. FIG. 12 is a diagram showing the optical system and crystal grains of the fifth variant.

In the fifth modification, an illumination device 45 constituted by a surface-emitting coaxial illumination device is provided below the lens unit 44b.

As shown in the ALS of FIG. 12 , the lighting device 45 includes a surface-emitting light source 45 a and a half mirror 45 b .

For example, LEDs (Light Emitting Diodes) or ELs (Electronic Luminescents) are arranged in an array to form a surface-emitting light source 45a. By adjusting the lighting area of the light source 45a, the inclination of the grain D can be detected. As shown in CLS of FIG12 , the control unit 80 limits the lighting area to the central portion or a portion by circuit control, etc., and determines the presence or absence of the inclination of the grain by detecting the mirror image MI that is irradiated into the grain D. Here, the lighting device 45 is limited to a circular area in the central portion and irradiates the same lighting light as the lighting device of the circular light source.

As shown in BLS of FIG12 , a liquid crystal panel 45c may be provided on the light-emitting surface of the light source 45a to adjust the lighting area. This makes it possible to control the lighting area arbitrarily and with high freedom. Here, the lighting device 45 is limited to a rectangular area to irradiate the same lighting light as the strip lighting device.

By configuring the lighting device 45 as a coaxial lighting device as shown in BLS of Fig. 12, it is possible to form the lighting light of the ring lighting of the embodiment, the lighting light of the circular light source (point light source) of the first modification, and the lighting light of the strip lighting of the second modification. This makes it possible to check the methods of the embodiment, the first modification, and the second modification.

Even though a telecentric lens is not used as in the fourth modification, the fifth modification can still transform illumination into a point light source. Thus, since the light irradiated to each position on the surface of the grain D is limited, detailed unevenness can be grasped, and quality control for defects caused by the presence or absence of unevenness is possible.

As mentioned above, the present invention is specifically described based on the implementation forms and modification examples, but the present invention is not limited to the above-mentioned implementation forms and modification examples, and various modifications can of course be implemented.

Embodiments and Modifications In order to confirm the mirror image of the surface of the grain D, the illumination light may be diffuse light or parallel light.

In the embodiment, the lighting device is described by taking a ring lighting device as an example, but the ring lighting device is not limited to a circular shape, and may also be a polygonal ring lighting device.

In the first modification, the lighting device is described by taking a circular lighting device as an example, but the circular lighting device is not limited to a circular shape, and may be a circular ring lighting device (ring lighting device) or a polygonal ring lighting device.

It is best to set the substrate recognition camera perpendicular to the surface of the substrate S, but depending on the situation, it can also be photographed at an angle using a Scheimpflug lens or the like.

It is best that the light source has a clear outline, but it may be blurred after passing through a diffuser, etc. In this case, the position or shape of the mirror image is determined by using binary transformation processing, etc. on the image processing side.

Alternatively, a photographic image of the grain D when it is horizontal may be retained as a template, and compared with the mirror image during inspection to detect changes in the inclination of the grain D. In this case, the comparison is performed by image difference processing or the like.

When multiple lighting devices are installed, the color of each lighting can be changed, and a color camera can be used. This makes it possible to process the same shot.

The height of the lighting device may be set to match the lens or camera, or not.

It is best if the camera lens has a focus adjustment function so that the image is focused, but even if the image is not focused and blurred to a certain extent, it is also acceptable.

The shape of the lighting area can be changed by, in addition to the circuit control of LED or EL and liquid crystal, split synchronization control with the lighting unit, a cover with a through hole, etc.

Furthermore, the embodiment describes an example in which a paste is used as an adhesive, but DAF (Die Attach Film) may also be used.

In addition, the embodiment is described as an example in which the intermediate platform section 30 is provided between the wafer supply section 10 and the bonding section 40, the pick-up head 21 places the die D picked up from the wafer supply section 10 on the intermediate platform 31, and the bonding head 41 picks up the die D again from the intermediate platform 31 and bonds it to the conveyed substrate S. However, the bonding head 41 may bond the die D picked up from the wafer supply section 10 to the substrate S.

1: Die bonding machine (semiconductor manufacturing equipment) 44: Substrate recognition camera (recognition camera) 45: Lighting device 46: Bonding platform (platform) 80: Control unit (control device)

[FIG. 1] is a top view schematically showing a die bonding machine of an embodiment. [FIG. 2] is a view schematically showing the structure when viewed from the direction of arrow A in FIG. 1. [FIG. 3] is a side view schematically showing the preform shown in FIG. 1. [FIG. 4] is a block diagram schematically showing the structure of the control system of the die bonding machine shown in FIG. 1. [FIG. 5] is a flow chart showing a method for manufacturing a semiconductor device using the die bonding machine shown in FIG. 1. [FIG. 6] is a diagram showing an optical system, a die, and an image of the bonding part shown in FIG. 1. [FIG. 7] is a diagram showing an optical system, a die, and an image of a first variant. [FIG. 8] is a diagram showing an optical system, a die, and an image of a second variant. [FIG. 9] is a diagram showing a method for moving a mirror position. [FIG. 10] is a diagram showing the configuration of a strip lighting device of a third variant. [Figure 11] is a diagram showing the optical system and crystal grains of the fourth variant. [Figure 12] is a diagram showing the optical system and crystal grains of the fifth variant.

44: Substrate recognition camera (recognition camera)

44a: Camera body unit

44b: Lens unit

45: Lighting device

D: Grain

C1,C3: Angle

MI:Mirror Image

IR: Photographic range

Claims (19)

A semiconductor manufacturing device, characterized by comprising: a platform that holds a substrate to which a die is bonded by a bonding head; an identification camera that is disposed above the substrate; an illumination device that is disposed above the substrate; and a control device that is configured to irradiate the die with illumination light by the illumination device and to photograph the die by the identification camera, and to inspect the bonding state of the die based on the presence or absence of a mirror image of the illumination light, the position of the mirror image of the illumination light, the shape of the mirror image of the illumination light, or the distribution of the brightness of the mirror image of the illumination light. A semiconductor manufacturing device as claimed in claim 1, wherein the control device is configured to determine whether the crystal grain is tilted based on the presence or absence of a mirror image of the illumination light and the position or shape of the mirror image. A semiconductor manufacturing device as claimed in claim 2, wherein the lighting device is a ring lighting device arranged around a lens of the recognition camera, and the recognition camera is arranged so that the die is located on the optical axis of the recognition camera. The semiconductor manufacturing device of claim 3, wherein the lighting device is composed of a plurality of annular lighting devices arranged in a concentric ring shape, and the control device is configured to sequentially light up the plurality of annular lighting devices, and photograph the crystal grain with the recognition camera at each lighting time, and determine the inclination or direction of the crystal grain according to the position of the mirror image of the illumination light of the annular lighting device. The semiconductor manufacturing device of claim 2, wherein the lighting device is a circular lighting device or an annular lighting device having a circular light source or a point light source and is disposed near the lens of the recognition camera. When the die is bonded to the substrate in parallel, the die is disposed at a position away from the center of the field of view of the recognition camera, so that the mirror image of the lighting light of the lighting device can be illuminated at the center of the die. The semiconductor manufacturing device of claim 5, wherein the lighting device is composed of the circular lighting device or the annular lighting device and a plurality of annular lighting devices arranged in a concentric ring shape outside the circular lighting device or the annular lighting device, The control device is configured to sequentially light up the circular lighting device or the annular lighting device and the plurality of annular lighting devices, and photograph the crystal grain with the recognition camera at each lighting time, and determine the tilt amount or direction of the crystal grain according to the position of the illumination mirror image of the circular lighting device or the annular lighting device and the plurality of annular lighting devices. A semiconductor manufacturing device as claimed in claim 1, wherein the die is a die stacked on the die bonded to the substrate offset in a first direction, the lighting device is a strip lighting device disposed in a second direction opposite to the first direction relative to the recognition camera, and the control device is configured to determine whether the die is warped based on the presence or absence of a mirror image of the illumination light of the strip lighting device. The semiconductor manufacturing device of claim 7, wherein the lighting device is composed of a plurality of strip lighting devices, and the control device is configured to sequentially light up the plurality of strip lighting devices and photograph the crystal grain with the recognition camera at each lighting time, and to determine the warp amount of the crystal grain according to the position of the mirror image of the illumination light of the plurality of strip lighting devices. A semiconductor manufacturing device as claimed in claim 7, wherein the control device is configured to move the position of the strip lighting device or the position of the identification camera or the position of the crystal grain while photographing the crystal grain with the identification camera at each position of the strip lighting device, and determine the amount of warp of the crystal grain based on the position of the mirror image of the illumination light of the strip lighting device. The semiconductor manufacturing device of claim 7, wherein the lighting device further comprises: a second strip lighting device disposed in the first direction relative to the recognition camera; a third strip lighting device disposed in a third direction orthogonal to the first direction relative to the recognition camera; and a fourth strip lighting device disposed in a fourth direction opposite to the third direction relative to the recognition camera. A semiconductor manufacturing device as claimed in claim 7, wherein the control device is configured to move the strip lighting device in the first direction or the second direction or a third direction orthogonal to the recognition camera and the first direction or a fourth direction orthogonal to the recognition camera and the third direction, to irradiate the lighting light, and to determine whether the grain is warped based on the presence or absence of a mirror image of the lighting light. The semiconductor manufacturing device of claim 7, wherein the lighting device further comprises a second strip lighting device disposed in the first direction relative to the recognition camera, and the control device is configured to illuminate the second strip lighting device with lighting light and photograph the crystal grain with the recognition camera, and to determine whether the crystal grain sags based on the presence or absence of a mirror image of the lighting light from the second strip lighting device. A semiconductor manufacturing device as claimed in claim 7, wherein the control device is configured to move the strip lighting device in the first direction to irradiate the lighting light, and determine whether the grain has drooped based on the presence or absence of a mirror image of the lighting light. A semiconductor manufacturing device as claimed in claim 1, wherein the lighting device is a lens insertion type coaxial lighting device possessed by the identification camera. A semiconductor manufacturing device as claimed in claim 1, wherein the lighting device is a coaxial lighting device having a surface-emitting light source and is disposed below a lens of the recognition camera, and the control device is configured to limit the lighting area of the surface-emitting light source to only the central portion or a portion. A semiconductor manufacturing device as claimed in claim 4 or 6, wherein the control device is configured to report an error when the tilt amount of the grain is judged to be above a predetermined value, or to record the defect of the grain, or to re-pressurize the grain using the bonding head. A semiconductor manufacturing device as claimed in claim 4 or 6, wherein a syringe for applying the paste to a substrate is provided, the die is bonded to the substrate on which the paste is applied, and the control device is configured to adjust the amount of the paste applied according to the inclination and direction of the die. An inspection device, characterized by comprising: a platform that holds a substrate to which a crystal grain is bonded; an identification camera that is disposed above the substrate; an illumination device that is disposed above the substrate; and a control device that is configured to irradiate the crystal grain with illumination light by the illumination device and to photograph the crystal grain by the identification camera, and to inspect the state of the crystal grain based on the presence or absence of a mirror image of the illumination light, the position of the mirror image of the illumination light, the shape of the mirror image of the illumination light, or the distribution of the brightness of the mirror image of the illumination light. A method for manufacturing a semiconductor device, characterized by comprising: a step of carrying a substrate into a semiconductor manufacturing device, the semiconductor manufacturing device being equipped with a platform for holding the substrate, an identification camera disposed above the substrate, and an illumination device disposed above the substrate; a step of bonding a crystal grain to the substrate; and an inspection step of irradiating the crystal grain with illumination light by the illumination device and photographing the crystal grain by the identification camera, and inspecting the state of the crystal grain based on the presence or absence of a mirror image of the illumination light, the position of the mirror image of the illumination light, the shape of the mirror image of the illumination light, or the distribution of the brightness of the mirror image of the illumination light.

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