TW202002097A - Die bonder and manufacturing method of semiconductor devices for improving detection rate of coating pattern using paste-like adhesive applied to substrate - Google Patents

Abstract

The subject of the present invention is to solve the problem that the entire coating area for paste-like adhesive is difficult to be detected while the brightness of substrate surface is closer to that of a coating portion of the paste-like adhesive. The present invention provides a die bonder for (a) making a lighting device in a first state for capturing the image of the state of a substrate before coating an adhesive and capturing the image of the state of the substrate after coating the adhesive; (b) making the lighting device in a second state for capturing the image of the state of the substrate before coating the adhesive and capturing the image of the state of the substrate after coating the adhesive; (c) calculating the binary data of the difference between the captured image of the state after coating while the lighting device is in the first state and the captured image of the state before coating; (d) calculating the binary data of the difference between the captured image of the state after coating while the lighting device is in the second state and the captured image of the state before coating; and (e) synthesizing the binary data calculated while the lighting device is in the first state with the binary data calculated while the lighting device is in the second state to obtain the adhesive coating pattern.

Description

Die bonder and method of manufacturing semiconductor device

The present disclosure relates to a die bonder, which can be applied to a die bonder having a preformed portion, for example.

A part of the manufacturing process of the semiconductor device includes a process of assembling a package by mounting a semiconductor wafer (hereinafter, simply referred to as a die) on a wiring board or a lead frame (hereinafter, simply referred to as a substrate), and a part of the process of assembling the package, The process (slicing process) of dividing a die from a semiconductor wafer (hereinafter simply referred to as a wafer), and the joining process of mounting the divided die on a substrate. The semiconductor manufacturing device used in the bonding process is a die bonder.

The die bonder is a device that uses solder, gold plating, and resin as bonding materials to bond (mount and attach) the die to the substrate or the die that has been bonded. In a die bonder that bonds a die, for example, to the surface of a substrate, the die is repeatedly sucked and picked up from the wafer by using an adsorption nozzle called a chuck, transferred to the substrate, and a pushing force is applied , And the joining material is heated to perform the joining operation (work).

When resin is used as a bonding material, resin pastes such as Ag epoxy and acrylic are used as adhesives (hereinafter referred to as paste adhesives). The paste adhesive that bonds the die to the lead frame or the like is enclosed in the syringe. The syringe moves the lead frame up and down to eject the paste adhesive and apply it. That is, with the syringe enclosed with the paste adhesive, the paste adhesive is applied in a specific amount at a specific position, and the die is pressed onto the paste adhesive to be bonded.

In the vicinity of the syringe, a recognition camera is installed, and it is confirmed with the recognition camera whether or not the pasted adhesive to be applied is only applied to a specific position in a specific amount. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Application Publication No. 2013-197277

[Problems to be solved by the invention]

It is difficult to detect when the brightness of the surface of the substrate is close to the brightness of the coated part of the paste adhesive on the surface of the substrate coated with metal, when the paste adhesive such as epoxy resin is applied, etc. The coating area of the paste adhesive is comprehensive. The subject of the present disclosure is to provide a die bonder capable of improving the detection rate of the application pattern of the paste adhesive applied to the substrate. Other topics and novel features are obvious from the descriptions in this manual and the drawings of the attachment. [Means to solve the problem]

A brief description of the outline represented in this disclosure will be as follows. That is, the die bonder system (a) puts the lighting device into the first state and the state before the application of the adhesive of the imaging substrate, and the image of the state after the application of the adhesive on the substrate, (b) Make the lighting device into the second state and image the state of the substrate before application of the adhesive, and image the state of the adhesive on the substrate after application, (c) find the The binarized data of the difference between the captured image captured in the first state and the captured image before the coating and the captured image before the coating is obtained (d) The binarized data of the difference between the captured image in the above-mentioned state after coating and the captured image in the state before the application, (e) synthesizing the binarized data obtained in the first state of the lighting device , And the binarized data obtained in the second state to obtain the adhesive coating pattern. [Effect of invention]

When the die bonder is used, the detection rate of the coating pattern of the paste adhesive applied to the substrate can be improved.

In the following, the embodiment, modification, comparative example and examples will be described using drawings. However, in the following description, the same constituent elements may be given the same symbols, and repeated description may be omitted. In addition, in order to make the description clearer, although the drawings are shown schematically in terms of the width, thickness, shape, etc. of each part compared to the actual form, this is only an example and is not intended to limit the interpretation of the present invention.

First, the application of the paste adhesive will be described using FIGS. 1 to 3. FIG. 1 is a diagram illustrating the application of paste adhesive. Fig. 2 is a diagram illustrating the application pattern of the paste adhesive, Fig. 2(a) is the shape of the × mark, Fig. 2(b) is the shape of the circle, and Fig. 2(c) is the combination of the shape of the × mark The shape of the Y shape is shown in Figure 2(d). Fig. 3 is a diagram illustrating the application state of the paste adhesive, Fig. 3(a) is a normal state, Fig. 3(b) is an insufficient state, Fig. 3(c) is a protruding state, and Fig. 3(d ) Is too much. In Figures 3 and 4, the black part is the substrate as the background, and the white part is the paste adhesive.

The application of the paste adhesive is performed by ejecting from the nozzle NZL at the front end of the syringe SYR enclosed in the paste adhesive as shown in FIG. 1(a), and applying it in accordance with the trajectory of the nozzle NZL. The syringe SYR is driven by the shape to be coated on the XYZ axis, and by its trajectory, drawing a × mark shape or a cross shape, etc., a free trajectory as shown in FIG. 2 is applied. In addition, as shown in FIG. 1(b), there is a stamp shape for processing the shape of the nozzle tip. Hereinafter, the application pattern of the paste adhesive will be described by the shape of the X mark in FIG. 2(a).

The die bonder has an inspection function for inspecting the state of the paste adhesive after application. As shown in FIG. 3, depending on the application state of the paste adhesive, there are insufficient (FIG. 3(b)), protruding (FIG. 3(c)), excessive (FIG. 3(d)), etc. In addition, FIG. 3(a) shows a case where the application state of the paste adhesive is normal. The inspection is performed by comparing the area or shape of the application area of the paste adhesive, whether it is close to the ideal shape, or comparing it with the memory of the application shape as the reference.

Next, the problem of the case of applying a paste adhesive such as epoxy resin on the surface of a substrate plated with metal plating such as palladium plating will be described using FIG. 4. FIG. 4 is a diagram for explaining the problem of the case where a paste adhesive is applied on the surface of a metal-plated substrate. FIG. 4(a) is a portrait of oblique illumination, and FIG. 4(b) is Figure 4(c) is a diagram showing the reflection of oblique light illumination. Figure 4(d) is a diagram showing the reflection of coaxial illumination. Figure 4(e) is a binarization of the portrait of oblique light illumination. Fig. 4(f) is a diagram in which the image of the coaxial illumination is binarized.

There are many cases where there is no uniformity on the plating surface, and the brightness of the plating surface is different and has deviations. As a result, the state at the time when the epoxy resin is applied is checked. The types or mixtures of epoxy resins are various, including transparent, colored and transparent, milky white, gray, and those containing metal particles. In addition, because it is liquid, its surface is specularly reflected, but there are also light penetrators. When the color or reflectance (brightness) of the plated surface on the substrate surface is close to the reflectance (brightness) of the epoxy resin coating part, the following phenomenon is caused, and it is difficult to detect the entire coating area of the paste adhesive. Here, the brightness depends on the reflectance and reflection angle. In addition, regardless of the presence or type of metal plating, substrate material, etc., the reflectivity of the substrate and the paste adhesive is close, especially when the reflectivity of the substrate side is slightly lower, there is the same problem.

Since the coating area is a liquid surface, the specular reflection is generated by the illumination, and bright lines or dark parts according to the position of the illumination are generated. For example, as shown in FIG. 4(a), a bright line BI appears in the periphery of the coating area and a dark portion DP appears in the center of the coating area by the oblique illumination. This is as shown in FIG. 4(c), because the oblique light illumination OL causes the incident direction of the illumination to be low. In addition, as shown in FIG. 4( b ), the image obtained by the coaxial illumination CL has a bright line BI in the center of the coating area, and a dark portion DP appears in the periphery of the coating area. This is as shown in FIG. 4(d), because the coaxial illumination CI causes the incident direction of the illumination to be high.

Even if the acquired image of the camera is binarized, it is affected by the background, and it is impossible to extract only the coated area. Furthermore, the realm of the bright part and the dark part is close to the brightness of the substrate surface, and these cannot be extracted in the binarization process. For example, as shown in FIG. 4(e), the image of oblique light illumination is binarized. As shown in FIG. 4(f), even if the image of oblique light illumination is binarized, it is impossible to extract only the coating area.

Next, an implementation form for solving the above-mentioned problems will be described using FIGS. 5 and 6. FIG. 5 is a diagram showing an optical system of an embodiment. 6 is a diagram illustrating image processing using the optical system of FIG. 5, FIG. 6(a) is a diagram showing image processing using oblique illumination, and FIG. 6(b) is a diagram showing image processing using coaxial illumination. Fig. 6(c) is a diagram synthesizing Fig. 6(a) and Fig. 6(b).

In the embodiment, the lighting device has a plurality of lighting states, and the images of the paste adhesive before and after the coating caused by each lighting state are acquired and subjected to differential processing. From the difference-processed image of each lighting state, the coating area is obtained by binarization processing. The calculated coating area is synthesized as a logical sum for each lighting state. According to this, the detection rate of the coating area (detectable coating area/actual coating area) can be improved.

For example, as shown in FIG. 5, oblique light illumination OL using the illumination device ID is used to obtain the images before and after coating by the camera CAM as the imaging device, and the differential image processing is performed to further binarize (FIG. 6(a) ). In addition, as shown in FIG. 5, the coaxial illumination CL of the illumination device ID is used, and the image before and after coating is acquired by the camera CAM, and differential image processing is performed to further binarize (FIG. 6(a)). As shown in FIG. 6(c), the difference portrait of FIG. 6(a) and the difference portrait of FIG. 6(b) are synthesized.

In the absolute value difference image processing, the influence of the uneven appearance of the background is removed, and the image is performed in a plurality of illumination states. By synthesizing this, the coating area of the paste adhesive PA is extracted. By changing the illumination irradiation position, etc., and changing the illumination state (for example, switching between coaxial illumination and oblique illumination), the bright line or dark part of the paste adhesive PA can be moved. Differential processing is carried out with moving images, and by synthesis, the coating area of the paste adhesive PA can be extracted.

Next, the reason why it is better to distinguish a plurality of lighting states (for example, lighting of distinguished lighting) will be described using FIG. 7. Fig. 7 is a diagram for explaining the reason for distinguishing the lighting of the two lights, and Fig. 7(a) is a portrait when a liquid is applied on a flat brightness surface. Fig. 7(b) is a graph showing the brightness distribution, the horizontal axis is the coordinate [×100], and the vertical axis is the brightness [×100]. 7(c) shows the difference with respect to the brightness before coating, the horizontal axis is the coordinate [×100], and the vertical axis is the brightness shift [×100].

When the liquid is applied to the flat and bright surface, the bright and dark parts are distributed in a sine wave shape. Also, change the position of the lighting so that the bright and dark parts move slightly. As shown in FIG. 7(a), the position of the lighting is set to A before the switch, and the switch is set to B after the switch. When the horizontal axis is set as the X coordinate and the vertical axis is set as the brightness, the brightness distribution becomes like the graph shown in FIG. 7(b). The solid line BA is the brightness of A, the solid line BB is the brightness of B, the dashed line BC is the brightness of lighting before and after the movement, and the dashed line BD is the brightness before coating.

FIG. 7(c) shows the difference (brightness shift) from the brightness (BD) before coating in FIG. 7(b). The vertical axis represents the brightness shift, and the horizontal axis represents the X coordinate. At the same time, the deflection of the lighting becomes a dotted line E, resulting in an area where the deflection cannot be obtained sufficiently in one-half cycle. For this, each difference is made, and the graphs superimposed after the absolute value calculation becomes the solid line F. It can be seen that the solid line F disappears from the area where the offset cannot be sufficiently obtained compared to the broken line E.

In the following, a few representative modifications of the embodiment will be exemplified. In the description of the following modified examples, it is assumed that the same symbols as those of the above-described embodiment can be used for the parts having the same configuration and function as those described in the above-mentioned embodiment. In addition, for the description of such a part, the description in the above-mentioned embodiments can be appropriately invoked within the scope of no technical contradiction. In addition, all or part of a part of the above-described embodiments and a plurality of modified examples can be used in an appropriate combination within a range where there is no technical contradiction.

In the embodiment, the switching of the illumination is described by taking coaxial illumination and oblique illumination as an example, but it is possible to switch the illumination state even in the following modified example. Select each switch to obtain the difference portrait before and after coating in each illumination. The image is switched every time before coating, and the switching is performed in the same order as after coating to obtain the image again. For example, in the lighting in the first state, the pre-coating and post-coating images of the paste adhesive are obtained to remove the influence of the appearance of the background substrate caused by the differential image processing. In the illumination of the second state, the pre-coating and post-coating images of the paste adhesive are obtained to remove the influence of the appearance of the background substrate caused by the differential image processing. Synthesize the different treatments caused by multiple continuous lighting in the first state and the second state to reduce the influence of the bright lines or dark parts mapped on the liquid surface of the paste adhesive. It is not limited to two lighting states of the first state and the second state, even if it is more than three lighting states.

(First modification) In the first modification, the illumination device switches the color of illumination (wavelength of illumination light) to obtain a plurality of illumination states. In addition to the three primary colors of red, green, and blue, white, infrared, ultraviolet, etc. are used for the color of the illumination. When using light other than visible light, use a camera whose wavelength holds the light receiving sensitivity. The spectroscopic reflection characteristics of the plated surface of the substrate and the surface of the paste adhesive are different.

(Second modification) In the second modification, the illumination device switches the irradiation direction of oblique illumination to obtain a plurality of illumination states. 8 is a plan view showing the arrangement of a lighting device according to a second modification.

As shown in FIG. 8, the lighting device includes plural oblique lighting OL1 to OL8. The oblique light illumination OL1, OL3, OL5, OL7 is configured such that the light is incident from near the corner of the substrate S to the center of the substrate S, and the oblique light illumination OL2, OL4, OL6, OL8 is configured such that the light faces the four sides of the substrate S respectively Is incident near the center of the substrate S. The control unit 8 controls the oblique light illumination OL1 to OL8 so as to light up for each irradiation direction.

The first state and the second state are formed by changing the oblique light illumination of lighting and the oblique light illumination of extinguishing. For example, as the first state of lighting, the oblique light is turned on to light OL1, OL3, OL5, OL7, and the oblique light is turned off to light OL2, OL4, OL6, OL8. As the second state of the lighting, the oblique lights OL1, OL3, OL5, OL7 are turned off, and the oblique lights OL2, OL4, OL6, OL8 are turned on.

It is not limited to two lighting states of the first state and the second state, even if it is more than three lighting states. For example, even in the first state, lighting oblique lighting OL1 and turning off other oblique lighting, in the second state, lighting oblique lighting OL2 and turning off other oblique lighting, ･･･, as the eighth state, lighting oblique lighting OL8 and Other oblique lighting can be turned off.

(Third modification) In the third modification, the lighting device has plural oblique light illumination, and the oblique light illumination is switched to obtain the plural illumination state. 9 is a perspective view showing an arrangement of oblique light illumination of a lighting device of a third modification.

As shown in FIG. 9, the lighting device includes complex oblique lighting OL1 to OL3 with different irradiation angles. The control unit 8 controls the oblique lighting OL1 to OL3 so as to light up for each irradiation direction. For example, in the first state, the oblique lighting OL1 is turned on and the oblique lighting OL2 and OL3 are turned off. In the second state, the oblique lighting is on the OL2 and the oblique lighting is turned off OL1 and OL3. Even in the second state, it is possible to turn on the oblique light illumination OL3 and turn off the oblique light illumination OL1, OL2. In addition, even if the third state is set so that the lighting is oblique lighting OL3 and the lighting oblique lighting OL1, OL2 may be turned off.

(Fourth Modification) In the fourth modification, the lighting device moves oblique light to obtain a plurality of lighting states. 10 is a schematic perspective view showing a lighting device of a fourth modification.

In the case of the second modification, although oblique light illumination of the lighting device is fixed, as shown in FIG. 10, in the fourth modification, bar-type oblique light illumination (oblique light rod illumination) BLD1 to BLD4 are provided. The control unit 8 controls the oblique light rods BLD1 to BLD4 to rotate in the horizontal direction of the arrow direction. For example, in the first state, the diagonal light rods BLD1 to BLD4 are arranged to face the four sides of the substrate S, and in the second state, the diagonal light rods BLD1 to BLD4 are rotated to be arranged at the four corners of the substrate S. It is not limited to the second state being rotated 45 degrees relative to the first state, and it may be any angle greater than 0 degrees and less than 90 degrees. In addition, in the case of being smaller than 45 degrees, even three or more states may be provided.

(Fifth Modification) In the fifth modification, the region illuminated by the oblique light ring is divided, and the lighting position is switched to obtain a plurality of lighting states. 11 is a schematic perspective view showing a lighting device of a fifth modification.

In the case of the embodiment, the second modification, and the third modification, although the oblique light bar lighting device is used, in the fifth modification, as shown in FIG. 11, a ring-shaped oblique light illumination (oblique light ring illumination) is used In RLD, the areas R1 to R8 can be turned on and off in each area. The control unit 8 controls the oblique ring illumination RLD so that the respective regions R1 to R8 are lit.

The first state and the second state are formed by changing the lighting area and the light-off area. For example, as the first state of illumination, the lighting regions R1, R2, R3, R4, and the lighting regions R5, R6, R7, R8. As the second state of illumination, the light-off areas R1, R2, R3, R4, and the light-up areas R5, R6, R7, R8.

It is not limited to two lighting states of the first state and the second state, even if it is more than three lighting states. For example, even in the first state, the lighting area R1 turns off other areas, in the second state, the lighting area R2 turns off other areas, and in the eighth state, the lighting area R8 turns off other oblique lighting. can.

(Sixth modification) In the sixth modification, parallel light and diffused light are switched in coaxial illumination to obtain a plurality of illumination states. 12 is a schematic side view showing a lighting device according to a sixth modification, FIG. 12(a) is a side view showing a state in which coaxial illumination irradiates parallel light, and FIG. 12(b) is a side showing a state in which coaxial illumination irradiates diffused light. view.

The coaxial illumination CL1 has coaxial illumination as shown in FIG. 12(a), in which lenses LN1, LN2 and a half mirror HM1 are provided on the light emitting surface of the illumination LS1 to output parallel light, and as shown in FIG. 12(b), the illumination The light emitting surface of LS2 is provided with a diffuser plate DP1 and a half mirror HM2 to output diffused light for coaxial illumination. The control unit 8 controls the turning on and off of the lighting LS1 and LS2, and performs switching between the oblique light illumination of FIG. 12(a) in the first state and the oblique light illumination of FIG. 12(b) in the second state.

(Seventh Modification) In the seventh modification, parallel light and diffused light are switched in oblique light illumination to obtain a plurality of illumination states. Fig. 13 is a schematic side view showing a lighting device according to a seventh modification, Fig. 13(a) is a side view showing a state in which oblique light illumination radiates parallel light, and Fig. 13(b) is a side showing a state in which oblique light illumination radiates diffused light view.

As shown in FIG. 13(a), a lens LN3 is provided on the light emitting surface of oblique light illumination OL to output parallel light, and as shown in FIG. 13(b), a diffusion plate DP2 is provided on the light emitting surface of oblique light illumination OL And the state of output diffused light. The control unit 8 controls the switching of the lens LN3 and the diffusion plate DP2, and performs the switching of the state of FIG. 13(a) as the first state and the state of FIG. 13(b) as the second state.

In addition, by combining the seventh modification with the sixth modification, four lighting states can be obtained.

(Eighth Modification) In the eighth modification, the polarization direction or phase is switched to obtain a complex illumination state. 14 is a schematic perspective view showing an illumination device of an eighth modification.

A polarizing filter PF1 or a wave plate WP1 is provided between the illumination LS3 and the paste adhesive PA, and a polarizing filter PF2 and a wave plate WP2 are provided between the paste adhesive PA and the camera CAM. The control unit 8 is controlled so that the polarizing filters PF1 and PF2 and the wavelength plates WP1 and WP2 can be attached and detached by a motor, or controlled so that the polarizing filters PF1 and PF2 can be rotated. Accordingly, the light irradiated to the paste adhesive PA and the light collected by the camera CAM are polarized (first state), or not polarized (second state), or the phase is shifted (third state), or By changing the polarization direction (fourth state), a portrait of the paste PA with different appearances can be obtained.

For an example of a lighting device to which an implementation type is applied, an example will be used for description. Even if the lighting device is any one or a combination of the first modification to the eighth modification. [Example]

The configuration of the die bonder of the embodiment will be described using FIGS. 15 to 17. 15 is a conceptual diagram of the die bonder of the embodiment viewed from above. 16 is a configuration diagram of the optical system of the die bonder of FIG. 15. Fig. 17 is a configuration diagram of the optical system of the preforming section of Fig. 16.

The die bonder 10 generally has a wafer supply unit 1, a workpiece supply conveying unit 2 and a die bond unit 3.

The wafer supply unit 1 includes a wafer cassette elevator 11 and a pickup device 12. The wafer cassette elevator 11 has a wafer cassette (not shown) that fills the wafer ring 16 and sequentially supplies the wafer ring 16 to the pickup device 12. The pickup device 12 moves the wafer ring 16 and pushes up the die D in such a manner that the desired die D can be picked up from the wafer ring 16.

The workpiece supply and conveying section 2 includes a stack loader 21, a frame feeder 22, and an unloader 23, and conveys a substrate S such as a lead frame in the direction of an arrow. The stack loader 21 supplies the substrate S to which the die D is bonded to the frame feeder 22. The frame feeder 22 conveys the substrate S to the unloader 23 via two processing positions on the frame feeder 22. The unloader 23 stores the substrate S that has been transported.

The die bonding portion 3 has a preformed portion (paste coating unit) 31 and a bonding head 32. The preformed part 31 applies the paste adhesive PA such as epoxy resin to the substrate S conveyed by the frame feeder 22 with the syringe 36. For the substrate S, for example, in the case where a plurality of unit lead frames are arranged in a row and connected in a series of multiple lead frames, a paste adhesive PA is applied to each label of the unit lead frame. Here, the substrate S is given palladium plating. The bonding head 32 picks up the die D from the pickup device 12 and rises, moving the die D to the bonding point on the frame feeder 22. Furthermore, the bonding head 32 lowers the crystal grain D at the bonding point, and bonds the crystal grain D to the substrate S coated with the paste adhesive PA.

The joint head 32 has a ZY drive shaft 60 that moves the joint head 35 up and down in the Z axis direction (height direction) and moves in the Y axis direction, and an X drive shaft 70 that moves in the X axis direction. The ZY drive shaft 60 has a Y axis direction indicated by an arrow C, that is, a Y drive shaft 40 that reciprocates the bonding head 35 between the pickup position in the pickup device 12 and the bonding point, and in order to pick up the die from the wafer 14 D or a Z drive shaft 50 that is joined to the substrate S and moves up and down. The X drive shaft 70 moves the entire ZY drive shaft 60 to the X direction, which is the direction in which the substrate S is transported.

As shown in FIG. 16, the optical system 88 has a preform optical system 33 that grasps the application position of the syringe 36, and a joint optical system 34 that grasps the joint position of the bonding head 35 to the transferred substrate S, and The wafer portion optical system 15 that grasps the pickup position of the die D picked up by the bonding head 35 from the wafer 14. Each optical system includes an illumination device and a camera that illuminate the object. For example, as shown in FIG. 17, the preforming part optical system 33 has an illumination device ID of coaxial illumination CL and oblique illumination OL, and a preform recognition camera 33a. The die D cut into a mesh shape in the wafer 14 is fixed to the dicing tape 17 that has been fixed to the wafer ring 16.

With this configuration, the paste adhesive PA is accurately applied to the correct position by the syringe 36, and the die D is surely picked up by the bonding head 35 and bonded to the correct position of the substrate S.

The control system 80 will be described using FIG. 18. 18 is a block diagram showing a schematic configuration of the control system of the die bonder of FIG. 15. The control system 80 includes a control unit 8, a drive unit 86, a signal unit 87, and an optical system 88. The control unit 8 mainly includes a control computing device 81 composed of a CPU (Central Processor Unit), a memory device 82, an input/output device 83, a bus bar 84, and a power supply unit 85. The memory device 82 has a main memory device 82a composed of a RAM storing a processing program and the like, and an auxiliary memory device 82b composed of an HDD or a control data or image data etc. required for control. The input/output device 83 has a screen 83a for displaying device status or information, a touch panel 83b for inputting instructions from an operator, a mouse 83c for operating the screen, and an image capturing device for capturing image data from the optical system 88 83d. In addition, the input/output device 83 includes a motor control device 83e that controls the drive unit 86 of the XY stage (not shown) of the wafer supply unit 1 or the ZY drive shaft of the bonding head stage, and various sensor signals or lighting devices. The I/O signal control device 83f which the signal part 87 of a switch etc. captures or controls a signal. The optical system 88 includes a wafer recognition camera of the wafer part optical system 15, a preform recognition camera 33a of the preform part optical system 33, and a substrate recognition camera of the joint part optical system 34. The control computing device 81 captures the required data via the bus bar 84 and performs calculations to control the pickup head 35 or the like or send the information to the screen 83a or the like.

The control unit 8 stores the image data captured by the optical system 88 in the memory device 82 via the image capturing device 83d. The software programmed based on the saved image data uses the control arithmetic device 81 to perform the positioning of the die D and the substrate S, the inspection of the coating pattern of the paste adhesive PA, and the surface inspection of the die D and the substrate S. Based on the positions of the die D and the substrate S calculated by the control computing device 81, the drive unit 86 is operated by the software via the screen control device 83e. Through this process, the positioning of the die D on the wafer 14 is performed, and the driving unit of the wafer supply unit 1 and the bonding unit 3 is operated to bond the die D to the substrate S. The identification camera used in the optical system 88 is gray scale, color, etc. to quantize the light intensity.

However, a syringe 36 for applying a paste-like adhesive is attached to the preformed portion 31 shown in FIG. 15. The syringe 36 is filled with a paste-like adhesive as described above, and the paste-like adhesive is pressed against the substrate S from the nozzle tip by air pressure and applied.

Whether the paste adhesive applied on the substrate S is applied in an appropriate position and in an appropriate amount is confirmed by the preform recognition camera 33a. To briefly explain the confirmation operation, the preform recognition camera 33a confirms the surface on which the paste adhesive PA should be applied. If there is no problem on the surface to be coated, the paste adhesive PA is coated from the syringe 36. The preform recognition camera 33a confirms again whether the paste adhesive PA is applied correctly after application. If there is no problem in coating, the die is mounted on the paste adhesive PA and the adhesion is completed.

The method for obtaining the inspection image of the paste adhesive PA will be described using FIGS. 19 and 20. FIG. 19 is a flowchart illustrating a method of acquiring the inspection image of the paste adhesive. FIG. 20 is a flowchart illustrating the inspection image processing of FIG. 19.

The control unit 8 lights only the coaxial illumination CL of the lighting device ID, and obtains an image (P1) of the surface of the substrate S before coating by the preform recognition camera 33a (step S1). Get multiple portraits with the required sensitivity.

The control unit 8 lights only the oblique light OL of the lighting device ID, and obtains an image (Q1) of the surface of the substrate S before coating by the preform recognition camera 33a (step S2). Get multiple portraits with the required sensitivity.

The control unit 8 applies the paste adhesive PA to the substrate S via the syringe 36 (step S3). In the case of multiple lead frames, the substrate S is coated with paste adhesive PA on all labels.

When acquiring a plurality of portraits, the control unit 8 performs an averaging operation of the plurality of portraits (P1) (step S4), and performs an averaging operation of the plurality of portraits (Q1) (step S5).

The control unit 8 lights only the coaxial illumination CL of the lighting device ID, and obtains the coated image (P2) by the preform recognition camera 33a (step S6). Get multiple portraits with the required sensitivity.

The control unit 8 lights only the oblique light OL of the lighting device ID, and obtains the coated image (Q2) by the preform recognition camera 33a (step S7). Get multiple portraits with the required sensitivity.

When acquiring a plurality of portraits, the control unit 8 performs an averaging operation of the plurality of portraits (P2) (step S8), and performs an averaging operation of the plurality of portraits (Q2) (step S9).

In the inspection image processing, as shown in FIG. 19, first, the control unit 8 performs difference processing between P1 and P2 to obtain difference data (ΔP) (step SA1). Next, the control unit 8 performs binarization processing of the difference data (ΔP) to obtain binarization data (ΔPB) (step SA2). Next, the control unit 8 performs difference processing between Q1 and Q2, and obtains difference data (ΔQ) (step SA3). Next, the control unit 8 performs the binarization process of the difference data (ΔQ) to obtain the binarization data (ΔQB) (step SA4). Next, the binarized data (ΔPB) and the binarized data (ΔQB) are synthesized to obtain the application area of the paste adhesive PA (step SA5).

The inspection is performed by comparing the area or shape of the coating area of the paste adhesive PA, whether it is close to the ideal shape, or comparing it with the memory of the coating shape to be the reference. Extraction of the area of the coating area counts pixels of a specific brightness (extraction from histogram data, etc.), using particle detection, etc. The comparison of the shape of the coating area can be maintained by copying or ideal shape, and the reference data that can be compared with the binarized data can be compared with the difference processing.

Next, a method of manufacturing a semiconductor device using the die bonder related to the embodiment will be described using FIG. 21. 21 is a flowchart showing a method of manufacturing a semiconductor device.

Step S11: Store the wafer ring 16 holding the dicing tape 17 of the die D divided from the wafer 14 in a wafer cassette (not shown), and carry it into the die bonder 10. The control unit 8 supplies the wafer ring 16 from the wafer cassette filled with the wafer ring 16 to the wafer supply unit 1. Furthermore, the substrate S is prepared and carried into the die bonder 10. The control unit 8 supplies the substrate S to the frame feeder 22 via the stack loader 21.

Step S12: The control unit 8 picks up the peeled die D from the wafer 14.

Step S13: The control unit 8 applies the paste adhesive PA from the syringe 36 to the substrate S conveyed by the frame feeder 22. The control unit 8 checks the paste adhesive PA applied in steps S1 to SA. The control unit 8 bonds the picked crystal grains D to the substrate S to which the paste adhesive PA is applied.

Step S14: The control unit 8 supplies the substrate S to which the die D is bonded to the unloader 23 via the frame feeder 22. The substrate S is carried out from the die bonder 10.

As described above, although the invention created by the present inventors is specifically described based on the embodiment, modification, and embodiment, the present invention is not limited to the above embodiment, modification, and embodiment, and of course various changes can be made.

For example, in the embodiment, although the example in which the die D picked up from the wafer 14 is bonded to the substrate S by the bonding head 35 is described, even if an intermediate platform is provided between the wafer 14 and the substrate S, the intermediate platform The die D picked up from the wafer 14 by the pickup head and the die D again picked up from the intermediate stage by the pickup head 35 may be bonded to the substrate S being transported.

Furthermore, in the examples, an example in which a paste-like adhesive such as epoxy resin is applied to the surface of a substrate plated with a metal plated with palladium plating or the like, but even on a resin substrate or a resin paste The combination can also be applied. It is effective when the reflectance of the substrate and the paste is close or especially when the substrate side is slightly lower.

1‧‧‧ Wafer Supply Department 2‧‧‧Work supply and transportation department 3‧‧‧Joint 10‧‧‧ Die Bonder 12‧‧‧ Pickup device 14‧‧‧ Wafer 15‧‧‧ Wafer Department Optical System 16‧‧‧wafer ring 17‧‧‧Cutting tape 32‧‧‧Join the head 33‧‧‧Preforming optical system 34‧‧‧ Joint optical system 35‧‧‧joint head 88‧‧‧Optical system 80‧‧‧Control system 81‧‧‧Control arithmetic device 82‧‧‧Memory device 83‧‧‧I/O device 84‧‧‧Bus bar 85‧‧‧Power Department D‧‧‧grain S‧‧‧Substrate CAM‧‧‧Camera ID‧‧‧Lighting CL‧‧‧coaxial lighting OL‧‧‧Oblique lighting PA‧‧‧ paste adhesive

FIG. 1 is a diagram illustrating the application of paste adhesive. FIG. 2 is a diagram illustrating the application pattern of the paste adhesive. FIG. 3 is a diagram explaining the application state of the paste adhesive. FIG. 4 is a diagram illustrating problems in the case of applying a paste-like adhesive on the surface of a substrate to which metal plating is applied. FIG. 5 is a diagram showing an optical system of an embodiment. FIG. 6 is a diagram illustrating image processing using the optical system of FIG. 5. FIG. 7 is a diagram illustrating the reason why it is better to distinguish two lightings. 8 is a plan view showing the arrangement of a lighting device according to a second modification. 9 is a perspective view showing an arrangement of oblique light illumination of a lighting device of a third modification. 10 is a schematic perspective view showing a lighting device of a fourth modification. 11 is a schematic perspective view showing a lighting device of a fifth modification. 12 is a schematic side view showing a lighting device according to a sixth modification. 13 is a schematic side view showing a lighting device according to a seventh modification. 14 is a schematic perspective view showing an illumination device of an eighth modification. 15 is a conceptual diagram of the die bonder of the embodiment viewed from above. 16 is a configuration diagram of the optical system of the die bonder of FIG. 15. Fig. 17 is a configuration diagram of the optical system of the preforming section of Fig. 16. 18 is a block diagram showing a schematic configuration of the control system of the die bonder of FIG. 15. FIG. 19 is a flowchart illustrating a method of acquiring the inspection image of the paste adhesive. FIG. 20 is a flowchart illustrating the inspection image processing of FIG. 19. 21 is a flowchart showing a method of manufacturing a semiconductor device.

Claims (16)

A die bonder with: Syringe, which is coated with paste adhesive on the substrate; A bonding head which mounts a die on the substrate coated with the adhesive; A lighting device, which is installed near the syringe and irradiates the imaging object with light in the first state and the second state; Cameras for identification; and The control device controls the above-mentioned lighting device and the above-mentioned recognition camera, The above control device Bringing the illumination device into the first state and imaging the state of the substrate with the adhesive before application by the recognition camera, and imaging the state of the adhesive on the substrate after application, The illumination device is brought into the second state, and the identification camera is used to image the state of the substrate before the application of the adhesive, and the state of the adhesive on the substrate after the application, Obtaining the binarized data of the difference between the captured image captured in the first state of the illumination device in the post-coating state and the captured image before the coating, Obtaining the binarized data of the difference between the captured image captured in the second state of the illumination device in the post-coating state and the captured image before the coating, Synthesizing the binarized data obtained in the first state of the lighting device and the binarized data obtained in the second state to obtain the adhesive coating pattern. The die bonder as recited in claim 1, wherein The substrate is a lead frame plated with metal. The die bonder as described in claim 1 or 2, wherein The photographed image is an image obtained by averaging the images obtained by plural imaging. The die bonder as described in claim 1 or 2, wherein The first state of the lighting device is illuminated by light of coaxial illumination, and the second state is illuminated by light of oblique light illumination. The die bonder as described in claim 1 or 2, wherein The control device switches the wavelength of the illumination light to bring the illumination device into the first state and the second state. The die bonder as described in claim 1 or 2, wherein The above-mentioned lighting device includes plural oblique light illuminations with different irradiation directions, The control device controls turning on and turning off of the oblique light illumination so that the lighting device is brought into the first state and the second state. The die bonder described in claim 6, wherein The above-mentioned oblique light illumination systems have different irradiation directions in the horizontal direction. The die bonder described in claim 6, wherein The oblique light illumination system has different irradiation directions in the vertical direction. The die bonder as described in claim 1 or 2, wherein The above-mentioned lighting device includes plural oblique light illuminations with different irradiation directions, The control device controls the movement of the oblique light illumination so that the illumination device is brought into the first state and the second state. The die bonder as described in claim 1 or 2, wherein The above-mentioned lighting device has a circular oblique light illumination with a plurality of areas, The control device controls the lighting and extinguishing of each of the areas of the circular oblique light illumination so that the lighting device is brought into the first state and the second state. The die bonder as described in claim 1 or 2, wherein The above-mentioned lighting device is a lighting device capable of irradiating parallel light and diffused light, The control device controls the switching of the parallel light and the diffused light to bring the lighting device into the first state and the second state. The die bonder as recited in claim 11, wherein The illumination device includes coaxial illumination for illuminating the parallel light and illumination for illuminating the diffused light. The die bonder as described in claim 1 or 2, wherein The above-mentioned lighting device includes a polarizing filter or a wavelength plate, The control device controls the presence or rotation of the polarizing filter, or the presence or absence of the switching of the wavelength plate, so that the lighting device is brought into the first state and the second state. A method of manufacturing a semiconductor device, including: (a) Moving into the wafer ring holder that holds the dicing tape to which the die is attached; (b) The process of moving into the substrate; (d) The process of picking up the above grains; (d) The project of applying paste adhesive on the above substrate; and (e) The process of joining the picked crystal grains to the substrate, The above (d) project includes: (d1) The process of bringing the lighting device into the first state and imaging the state of the substrate before application of the adhesive; (d2) The process of switching the lighting device to the second state and imaging the state of the substrate before application of the adhesive; (d3) The process of switching the lighting device to the first state and imaging the applied state of the adhesive on the substrate; (d4) The process of switching the illumination device to the second state and imaging the applied state of the adhesive on the substrate; (d5) The process of obtaining the difference between the captured image in the first state and the post-coating state of the lighting device and the captured image in the pre-coating state, and obtaining a binary data of the difference; (d6) The process of obtaining the difference between the captured image in the second state and the captured image in the second state of the illumination device and the captured image in the state before coating, and obtaining a binary data of the difference; (d7) A process of synthesizing the binarized data obtained in the first state of the lighting device and the binarized data obtained in the second state to obtain the adhesive coating pattern. The method for manufacturing a semiconductor device according to claim 14, wherein The above-mentioned (c) engineering department places the picked-up die on the intermediate platform, The above (e) process is to pick up the die mounted on the above intermediate platform. The method for manufacturing a semiconductor device according to claim 14, wherein The substrate is a lead frame plated with metal.

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