TWI702661B - Die bonder and manufacturing method of semiconductor device - Google Patents

Abstract

[Question] When the brightness of the substrate surface is close to the brightness of the application area of the paste adhesive, it is difficult to detect the entire application area of the paste adhesive. [Solution] The die bonder system (a) puts the lighting device in the first state and photographs the state before the application of the adhesive on the substrate, and the state after the application of the adhesive on the substrate, ( b) Put the lighting device in the second state and take an image of the state before the application of the adhesive on the substrate, and take the image of the state after the application of the adhesive on the substrate. (c) Obtain the illumination The binary data of the difference between the image captured in the first state of the device and the image captured in the state after coating and the image captured in the state before coating, (d) the second state of the lighting device The binarized data of the difference between the image taken in the state after the application and the image taken in the state before the application, (e) synthesize the two obtained from the first state of the lighting device Obtaining the adhesive coating pattern by using the quantized data and the binary data obtained in the second state.

Description

Die bonder and manufacturing method of semiconductor device

The present disclosure relates to die bonders, which can be applied to die bonders provided with, for example, a preform.

A part of the manufacturing process of a semiconductor device includes a process of mounting a semiconductor chip (hereinafter referred to as a die) on a wiring board or a lead frame (hereinafter referred to as a substrate) to assemble a package. As part of the process of assembling the package, A process of dividing a die from a semiconductor wafer (hereinafter referred to as a wafer) (dicing process), and a bonding process of mounting the divided die on a substrate. The semiconductor manufacturing equipment 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 adhere) die on a substrate or die that has already been bonded. In a die bonder that bonds dies, for example, to the surface of a substrate, it is repeatedly carried out by using suction nozzles called chucks to suck and pick up the dies from the wafer, transfer them to the substrate, and apply pressure , And heat the bonding material to perform bonding operations (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). Paste adhesive for bonding the die to the lead frame is enclosed in the syringe. The syringe moves up and down the lead frame to inject and apply the paste adhesive. That is, by using a syringe enclosed with a paste adhesive, the paste adhesive is applied to a specific position in a specific amount, and the die is pressed onto the paste adhesive to be bonded.

In the vicinity of the syringe, a recognition camera is installed, and the recognition camera is used to confirm whether the applied paste adhesive is only applied to a specific position in a specific amount. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] JP 2013-197277 A

[The problem to be solved by the invention]

It is difficult to detect when the surface of the metal-plated substrate is coated with paste adhesive such as epoxy resin, etc., and the brightness of the substrate surface is close to the brightness of the coated part of the paste adhesive. The coating area of the paste adhesive is all over. The subject of the present disclosure is to provide a die bonder that can improve the detection rate of the coating pattern of the paste adhesive applied on the substrate. Other topics and novel features are obvious from the description of this manual and the attached drawings. [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 in the first state and image the state before the application of the adhesive of the substrate, and image the state after the application of the adhesive on the substrate, (b) Bring the lighting device into the second state, take an image of the state of the substrate before the application of the adhesive, and image the state of the substrate after the application of the adhesive, and (c) obtain the The binarized data of the difference between the image taken in the state after the application and the image taken in the state before the application in the first state, and (d) obtain the image taken in the second state of the lighting device The binarized data of the difference between the photographed image in the state after the application and the photographic image in the state before the application, (e) synthesize the binary data obtained from the first state of the lighting device , And the binarized data obtained in the second state to obtain the adhesive coating pattern. [Effects of Invention]

If the above die bonder is used, the detection rate of the coating pattern of the paste adhesive applied on the substrate can be improved.

Hereinafter, implementation forms, modified examples, comparative examples, and examples are described using drawings. However, in the following description, the same components are denoted with the same symbols, and overlapping descriptions may be omitted. In addition, in order to make the description clearer, although there are diagrams that illustrate the width, thickness, and shape of each part more than the actual state, 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 Figures 1 to 3. Fig. 1 is a diagram illustrating the application of a paste adhesive. Figure 2 is a diagram illustrating the application pattern of the paste adhesive. Figure 2(a) shows the shape of ×, Figure 2(b) shows the shape of circle, and Figure 2(c) shows the combination of the shapes of × The shape of the Y shape, Figure 2 (d) is the frame shape. Figure 3 is a diagram illustrating the application state of the paste adhesive. Figure 3(a) is the normal state, Figure 3(b) is the insufficient state, Figure 3(c) is the protruding state, and Figure 3(d) ) Is too much status. 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 according to the trajectory of the nozzle NZL. The syringe SYR is driven on the XYZ axis by the shape to be coated, and the trajectory is drawn by a free trajectory such as an X mark shape or a cross shape as shown in Fig. 2 to be coated. In addition, as shown in Fig. 1(b), it has a stamp shape that processes the shape of the nozzle tip. Hereinafter, the coating pattern of the paste adhesive will be described with the shape of the X mark in Figure 2(a).

The die bonder has an inspection function to inspect the state of the paste adhesive after application. As shown in Figure 3, depending on the coating state of the paste adhesive, there are insufficient (Figure 3(b)), protrusion (Figure 3(c)), excessive (Figure 3(d)), etc. In addition, Fig. 3(a) shows that the application state of the paste adhesive is normal. The inspection is performed by comparing whether the area or shape of the application area of the paste adhesive is close to the ideal shape, or comparing with the application shape that has become a reference in memory.

Next, the problem of the case where a paste adhesive such as epoxy resin is applied to the surface of the substrate to which metal plating such as palladium plating is applied will be described using FIG. 4. Figure 4 is a diagram illustrating the problem of applying paste adhesive on the surface of a substrate to which metal plating is applied. Figure 4(a) is a portrait of oblique lighting, and Figure 4(b) is Figure 4(c) is a diagram showing the reflection of oblique illumination, Figure 4(d) is a diagram showing the reflection of coaxial illumination, and Figure 4(e) is a binary image of the oblique illumination. Fig. 4(f) is a diagram that binarizes the image of coaxial illumination.

There are many cases where there is no uniformity on the plating surface, and the brightness of the plating surface is different and uneven. Then, it becomes the state when the epoxy resin is applied. There are various types or mixtures of epoxy resins, including transparent, colored transparent, milky white, gray, and those containing metal particles. Furthermore, because it is liquid, its surface is specularly reflective, but there are also light penetrating ones. When the color or reflectance (brightness) of the plated surface of the substrate surface is close to the reflectance (brightness) of the epoxy coating part, the following phenomena are caused, and it is difficult to detect the entire coating area of the paste adhesive. Here, brightness depends on reflectivity and reflection angle. Furthermore, regardless of the presence or absence of metal plating, the type, the material of the substrate, etc., the reflectivity of the substrate and the paste adhesive are close, especially when the reflectivity of the substrate side is slightly lower, the same problem occurs.

Because the coating area is a liquid surface, the illumination produces a specular reflection to produce bright lines or dark parts depending on the position of the illumination. For example, as shown in FIG. 4(a), the image obtained by oblique lighting has a bright line BI at the periphery of the coating area, and a dark part DP at the center of the coating area. This is as shown in Figure 4(c), because OL is illuminated with oblique light, and the incident direction of the illumination is 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 part DP in the periphery of the coating area. This is as shown in Figure 4(d), because the incident direction of the illumination is high in the coaxial illumination CI.

Even if the image obtained by the camera is binarized, it is affected by the background and cannot only extract the coated area. Furthermore, the boundary between 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 obliquely illuminated image is binarized, and as shown in Fig. 4(f), even if the obliquely illuminated image is binarized, it is impossible to extract only the coating area.

Next, the implementation type 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 implementation type. Fig. 6 is a diagram illustrating the image processing using the optical system of Fig. 5, Fig. 6(a) is a diagram showing the image processing using oblique light illumination, and Fig. 6(b) is a diagram showing the image processing using coaxial illumination , Figure 6(c) is a composite diagram of Figure 6(a) and Figure 6(b).

In the implementation type, the lighting device has a plurality of lighting states, and the image of the paste adhesive caused by each lighting state is obtained before and after the application, and the difference is processed. From the image processed by the difference of each lighting state, the coating area is obtained by the binarization process. The calculated coating area is combined for each lighting state as a logical sum. According to this, the detection rate of the coating area (detectable coating area/actual coating area) can be improved.

For example, as shown in Figure 5, using the oblique light OL of the lighting device ID, the camera CAM as the imaging device obtains the images before and after coating, and performs the differential image processing to further binarize (Figure 6(a)) ). Furthermore, as shown in FIG. 5, using the coaxial lighting CL of the lighting device ID, the image before and after coating is obtained by the camera CAM, and the difference image processing is performed to further binarize (FIG. 6(a)). As shown in Fig. 6(c), the difference image in Fig. 6(a) and the difference image in Fig. 6(b) are combined.

In the absolute value difference image processing, the influence of the uneven appearance of the background is removed, and the image in the plural illumination state is used, and by synthesizing this, the application area of the paste adhesive PA is extracted. By changing the illumination position, etc., changing the illumination state (for example, switching between coaxial illumination and oblique illumination), the bright lines or dark parts of the paste adhesive PA can be moved. Differential processing is performed on the moving images, and the application area of the paste adhesive PA can be extracted by synthesis.

Next, the reason why it is better to distinguish plural lighting states (for example, to distinguish the lighting of the lighting) will be explained using FIG. 7. Fig. 7 is a diagram for explaining the reason why the lighting of the two lights is better. Fig. 7(a) is an image 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]. Fig. 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 offset [×100].

When the liquid is applied to the flat brightness surface, the bright and dark parts are distributed in a sine wave shape. Also, change the position of the lighting to slightly move the bright and dark parts. As shown in Figure 7(a), set the lighting position as A before switching, and B after switching. When the horizontal axis is the X coordinate and the vertical axis is 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 simultaneous lighting before and after the movement, and the dashed line BD is the brightness before coating.

Fig. 7(c) shows the difference (brightness shift) of the brightness (BD) before coating from Fig. 7(b). The vertical axis represents the luminance shift, and the horizontal axis represents the X coordinate. At the same time, the deviation of the lighting becomes the dotted line E, resulting in an area where the deviation cannot be sufficiently obtained in a 1/2 cycle. In this regard, each difference is made, and the superimposed graph becomes a solid line F after the absolute value calculation. 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.

Hereinafter, a few examples are given for representative modification examples of implementation types. In the description of the following modification examples, it is assumed that the same symbols as those of the above-mentioned embodiment can be used for parts having the same configuration and function as those described in the above-mentioned embodiment. Moreover, for such part of the description, within the scope of no technical contradiction, the description in the above-mentioned embodiment can be appropriately used. Furthermore, part of the above-mentioned embodiments and all or part of the plural modifications are within the scope of technically non-contradictory, and can be used appropriately and in a complex manner.

In the implementation mode, the switching of lighting is described with coaxial lighting and oblique lighting as examples, but it is also possible to switch the lighting state of the following modification examples. Select each switch to obtain the different images before and after coating in each lighting. Each time you switch to obtain the image before coating, the switching is performed in the same order as after coating, and the image is obtained again. For example, in the first state of lighting, the image before and after application of the paste adhesive is obtained, and the effect of the appearance of the background substrate caused by the different image processing is removed. In the second state of lighting, the image before and after application of the paste adhesive is obtained, and the effect of the appearance of the background substrate caused by the different image processing is removed. Synthesize the various differential treatments caused by multiple lightings such as the first state and the second state to reduce the impact of bright lines or dark parts mapped on the liquid surface of the paste adhesive. It is not limited to the 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 lighting device switches the color of the lighting (the wavelength of the lighting light) to obtain a plurality of lighting states. In addition to the three primary colors of red, green, and blue, the colors of the irradiated lighting use white, infrared, and ultraviolet. When using light other than visible light, use a camera whose wavelength has sensitivity to light. Utilize the difference in spectral reflection characteristics between the plating surface of the substrate and the surface of the paste adhesive.

(Second Modification) In the second modified example, the lighting device switches the irradiation direction of the oblique light lighting to obtain a plurality of lighting states. Fig. 8 is a plan view showing the arrangement of a lighting device of a second modification.

As shown in Fig. 8, the lighting device is provided with plural oblique lighting OL1 to OL8. The oblique light illumination OL1, OL3, OL5, OL7 are arranged so that the light is incident from the corner of the substrate S to the vicinity of the center of the substrate S, and the oblique light illumination OL2, OL4, OL6, OL8 is arranged so that the light opposes 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 in a manner of individually lighting for each irradiation direction.

Change the oblique lighting of lighting and the oblique lighting of turning off to form the first state and the second state. For example, as the first state of lighting, turn on oblique lights OL1, OL3, OL5, and OL7, and turn off oblique lights OL2, OL4, OL6, OL8. As the second state of lighting, turn off the oblique lighting OL1, OL3, OL5, OL7, and turn on the oblique lighting OL2, OL4, OL6, OL8.

It is not limited to the two lighting states of the first state and the second state, even if it is more than three lighting states. For example, even as the first state, the oblique light illumination OL1 is turned on and the other oblique light illumination is turned off, and as the second state, the oblique light illumination OL2 is turned on and the other oblique light illumination is turned off, ･･･, as the eighth state, the oblique light illumination OL8 is turned on and Turn off other oblique lighting.

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

As shown in FIG. 9, the illuminating device includes plural oblique light illuminations OL1 to OL3 with different illumination angles. The control unit 8 controls the oblique light illumination OL1 to OL3 in a manner of individually lighting for each irradiation direction. For example, as the first state, the diagonal lighting OL1 is turned on and the diagonal lighting OL2 and OL3 are turned off, and the diagonal lighting OL2 is turned on and the diagonal lighting OL1 and OL3 are turned off as the second state. Even as the second state, the diagonal lighting OL3 may be turned on and the diagonal lighting OL1 and OL2 may be turned off. In addition, the third state may be set to turn on the oblique lighting OL3 and turn off the oblique lighting OL1 and OL2.

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

In the case of the second modification example, although the oblique light illumination of the illuminating device is fixedly arranged, as shown in FIG. 10, in the fourth modification example, bar-shaped oblique light illumination (oblique light bar illumination) BLD1 to BLD4 is provided. The control unit 8 controls the oblique light bar illumination BLD1 to BLD4 to rotate in the horizontal direction of the arrow. For example, in the first state, the oblique light bar illuminations BLD1 to BLD4 are arranged to face the four sides of the substrate S, and in the second state, the oblique light bar illuminations BLD1 to BLD4 are rotated and arranged on the four corners of the substrate S. It is not limited to the second state being rotated by 45 degrees with respect to the first state, and it may be any angle greater than 0 degrees and less than 90 degrees. Furthermore, in the case of less than 45 degrees, it is possible to set more than three states.

(Fifth Modification) In the fifth modification, the area illuminated by the oblique halo is divided, and the lighting position is switched to obtain a plurality of illumination states. Fig. 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 rod illuminating 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 dimmed for lighting and extinguishing in each area. The control unit 8 controls the oblique light ring illumination RLD so as to light the respective areas R1 to R8.

The light-on area and the light-off area are changed to form the first state and the second state. For example, as the first state of lighting, lighting areas R1, R2, R3, R4, and light-off areas R5, R6, R7, R8. As the second state of lighting, light-off areas R1, R2, R3, R4, and lighting areas R5, R6, R7, R8.

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

(Sixth Modification) In the sixth modification, the parallel light and the diffused light are switched in the coaxial illumination to obtain a plural illumination state. Fig. 12 is a schematic side view showing the lighting device of the sixth modification, Fig. 12(a) is a side view showing the state of coaxial illumination irradiating parallel light, and Fig. 12(b) is the side showing the state of coaxial illumination irradiating diffused light view.

The coaxial illumination CL1 is equipped with coaxial illumination in which lenses LN1, LN2 and a half mirror HM1 are provided on the light-emitting surface of the illumination LS1 as shown in Fig. 12(a) to output parallel light, and as shown in Fig. 12(b), in the illumination The light-emitting surface of LS2 is configured with a diffuser DP1 and a half mirror HM2 to output diffused light coaxial illumination. The control unit 8 controls the lighting and extinguishing of the lights LS1 and LS2, and switches the oblique light illumination of FIG. 12(a) as the first state and the oblique light illumination of FIG. 12(b) as the second state.

(Seventh modification) In the seventh modification, parallel light and diffused light are switched in oblique light illumination to obtain a plural illumination state. Fig. 13 is a schematic side view showing the illumination device of the seventh modification, Fig. 13(a) is a side view showing the state of oblique light illumination irradiating parallel light, and Fig. 13(b) is the side showing the state of oblique light illumination irradiating diffused light view.

As shown in Figure 13(a), the lens LN3 is provided on the light emitting surface of the oblique light illumination OL to output parallel light, and as shown in Figure 13(b), the diffuser DP2 is provided on the light emitting surface of the oblique light illumination OL And output the state of diffused light. The control unit 8 controls the switching of the lens LN3 and the diffuser DP2, and switches between 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 example and the sixth modification example, four illumination states can be obtained.

(Eighth Modification) In the eighth modification, the polarization direction or phase is switched to obtain a complex illumination state. Fig. 14 is a schematic perspective view showing a lighting 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 wave 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 unpolarized (second state), or phase shifted (third state), or Change the direction of polarization (fourth state), and you can get different images of paste adhesive PA.

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

The structure of the die bonder of the embodiment will be described using FIGS. 15-17. Fig. 15 is a conceptual view of the die bonder of the embodiment viewed from above. Fig. 16 is a structural diagram of the optical system of the die bonder of Fig. 15. Fig. 17 is a configuration diagram of the optical system of the pre-forming part of Fig. 16.

The die bonder 10 roughly includes a wafer supply unit 1, a workpiece supply and transport unit 2, and a die bond unit 3.

The wafer supply unit 1 has a wafer cassette elevator 11 and a pickup device 12. The wafer cassette elevator 11 has a wafer cassette (not shown) for filling the wafer ring 16, and supplies the wafer ring 16 to the pickup device 12 in sequence. The pick-up device 12 moves the wafer ring 16 to push up the die D in a manner that can pick up the desired die D from the wafer ring 16.

The workpiece supply and transport unit 2 includes a stack loader 21, a frame feeder 22, and an unloader 23, and transports the substrate S such as a lead frame in the arrow direction. 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 being conveyed.

The die bonding part 3 has a preforming part (paste coating unit) 31 and a bonding head 32. The preformed part 31 applies a paste adhesive PA such as epoxy resin with a syringe 36 to the substrate S conveyed by the frame feeder 22. The substrate S is, for example, a case where a plurality of unit lead frames are arranged in a horizontal row and connected to form a series of multi-connected lead frames, and each label of the unit lead frame is coated with a paste adhesive PA. Here, the substrate S is plated with palladium. The bonding head 32 picks up the die D from the pick-up device 12 and rises to move the die D to the bonding point on the frame feeder 22. In addition, the bonding head 32 lowers the die D at the bonding point, and bonds the die D to the substrate S coated with the paste adhesive PA.

The joining head 32 has a ZY drive shaft 60 that moves the joining head 35 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, the Y drive shaft 40 that moves the bonding head 35 back and forth between the picking position in the picking device 12 and the bonding point, and for picking up the die from the wafer 14 D or the Z drive shaft 50 which is joined to the substrate S and raised and lowered. The X drive shaft 70 moves the entire ZY drive shaft 60 to the direction in which the substrate S is conveyed, that is, the X direction.

As shown in FIG. 16, the optical system 88 has a preform optical system 33 that grasps the coating position of the syringe 36, and a bonding portion optical system 34 that grasps the bonding position where the bonding head 35 is bonded to the substrate S being conveyed, 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 has an illuminating device and a camera for illuminating the object. For example, as shown in FIG. 17, the pre-forming part optical system 33 has the illuminating device ID of the coaxial illumination CL and oblique light OL, and the pre-forming recognition camera 33a. The die D cut into a mesh in the wafer 14 is fixed to the dicing tape 17 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 reliably 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. Fig. 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 roughly mainly includes a control arithmetic 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 storage device 82 has a main storage device 82a composed of RAM storing processing programs and the like, and an auxiliary storage device 82b composed of HDD or HDD storing control data or image data required for control. The input and 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. Furthermore, the input/output device 83 has 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 signals from various sensors or lighting devices I/O signal control device 83f that captures or controls the signal by the signal unit 87 of the switch etc. The optical system 88 includes a wafer recognition camera of the wafer portion optical system 15, a pre-molding recognition camera 33 a of the pre-forming portion optical system 33, and a substrate recognition camera of the bonding portion optical system 34. The control computing device 81 captures the required data via the bus bar 84 and performs calculations to control the pickup 35 etc. or send information to the screen 83a etc.

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. With software programmed according to the saved image data, the control computing device 81 is used to perform positioning of the die D and the substrate S, inspection of the coating pattern of the paste adhesive PA, and 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 arithmetic device 81, the drive unit 86 is operated by 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 part of the wafer supply part 1 and the bonding part 3 are operated to bond the die D to the substrate S. The recognition camera used in the optical system 88 is grayscale, color, etc., and the light intensity is digitized.

However, as shown in FIG. 15, a syringe 36 for applying a paste adhesive is attached to the preformed portion 31. The syringe 36 is filled with a paste adhesive as described above, and by air pressure, the paste adhesive is pressed from the tip of the nozzle onto the substrate S 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 pre-formed recognition camera 33a. To briefly explain the confirmation operation, the preform recognition camera 33a is used to confirm the surface to which the paste adhesive PA should be applied. If there is no problem on the surface to be coated, the paste adhesive PA is applied from the syringe 36. The preform recognition camera 33a reconfirms 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 bonding is completed.

For the method of obtaining the inspection image of the paste adhesive PA, use Figures 19 and 20 to illustrate. Fig. 19 is a flowchart illustrating a method of obtaining an inspection image of a 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 illuminating device ID, and obtains an image (P1) of the surface of the substrate S before coating by the pre-formed recognition camera 33a (step S1). Obtain complex images 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 pre-formed recognition camera 33a (step S2). Obtain complex images with the required sensitivity.

The control unit 8 applies the paste adhesive PA to the substrate S by the syringe 36 (step S3). When the substrate S is in a multi-connected lead frame, all labels are coated with a paste adhesive PA.

In the case of obtaining a complex portrait, the control unit 8 performs the averaging operation of the complex portrait (P1) (step S4), and performs the averaging operation of the complex portrait (Q1) (step S5).

The control unit 8 lights only the coaxial illumination CL of the illuminating device ID, and obtains the painted image (P2) by the preform recognition camera 33a (step S6). Obtain complex images with the required sensitivity.

The control unit 8 lights only the oblique light OL of the lighting device ID, and obtains the painted image (Q2) by the pre-form recognition camera 33a (step S7). Obtain complex images with the required sensitivity.

In the case of obtaining a complex portrait, the control unit 8 performs an averaging operation of the complex portrait (P2) (step S8), and performs an averaging operation of the complex portrait (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 the binarization processing of the difference data (ΔP), and obtains the binarized 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), and obtains the binarized 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 carried out by comparing whether the area or shape of the application area of the paste adhesive PA is close to the ideal shape, or comparing with the application shape that has become a reference in memory. Extraction of the area of the coating area counts pixels of specific brightness (extracted from histogram data, etc.), using particle detection, etc. The comparison of the shape of the coated area can be performed by profiling or ideal shape to keep the reference data that can be compared with the data after the binarization, and compare with this by differential processing.

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

Step S11: The wafer ring 16 holding the dicing tape 17 to which the die D divided from the wafer 14 is adhered is stored in a wafer cassette (without pattern), and carried 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. In addition, the substrate S is prepared and carried into the die bonder 10. The control section 8 supplies the substrate S to the frame feeder 22 through 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-up die 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 through the frame feeder 22. The substrate S is carried out from the die bonder 10.

Although the above description specifically describes the invention created by the inventor based on the embodiment, modification, and embodiment, the invention is not limited to the above embodiment, modification, and embodiment, and can of course be modified in various ways.

For example, in the embodiment, an 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. However, even if an intermediate stage is provided between the wafer 14 and the substrate S, the intermediate stage is loaded The die D picked up from the wafer 14 by the pick-up head may be picked up again from the intermediate stage by the pick-up head 35, and the die D may be bonded to the substrate S to be transported.

In addition, although the examples describe the example of applying a paste adhesive such as epoxy resin to the surface of the substrate to which metal plating such as palladium plating is applied, it is even for resin substrates and resin pastes. The combination can also be applied. It is effective when the reflectance of the substrate and the paste are close to each other, or especially when the substrate side is slightly lower.

1‧‧‧Wafer Supply Department 2‧‧‧Workpiece Supply and Transport Department 3‧‧‧Joint 10‧‧‧Die Bonder 12‧‧‧Pickup device 14‧‧‧wafer 15‧‧‧Wafer optical system 16‧‧‧Wafer Ring 17‧‧‧cutting tape 32‧‧‧Joint head 33‧‧‧Optical system for pre-forming part 34‧‧‧Joint Optical System 35‧‧‧Joint head 88‧‧‧Optical system 80‧‧‧Control system 81‧‧‧Control computing device 82‧‧‧Memory device 83‧‧‧Input and output device 84‧‧‧Busbar 85‧‧‧Power Department D‧‧‧grain S‧‧‧Substrate CAM‧‧‧Camera ID‧‧‧Lighting device CL‧‧‧Coaxial lighting OL‧‧‧oblique lighting PA‧‧‧Paste adhesive

Fig. 1 is a diagram illustrating the application of a paste adhesive. Fig. 2 is a diagram illustrating the application pattern of the paste adhesive. Fig. 3 is a diagram illustrating the application state of the paste adhesive. FIG. 4 is a diagram for explaining the problem of applying a paste adhesive to the surface of a substrate to which metal plating is applied. Fig. 5 is a diagram showing an optical system of an implementation type. Fig. 6 is a diagram illustrating image processing using the optical system of Fig. 5; Fig. 7 is a diagram illustrating the reason why the lighting of two lights is better. Fig. 8 is a plan view showing the arrangement of a lighting device of a second modification. Fig. 9 is a perspective view showing the arrangement of oblique lighting of the lighting device of the third modification. Fig. 10 is a schematic perspective view showing a lighting device of a fourth modification. Fig. 11 is a schematic perspective view showing a lighting device of a fifth modification. Fig. 12 is a schematic side view showing a lighting device of a sixth modification. Fig. 13 is a schematic side view showing a lighting device of a seventh modification. Fig. 14 is a schematic perspective view showing a lighting device of an eighth modification. Fig. 15 is a conceptual view of the die bonder of the embodiment viewed from above. Fig. 16 is a structural diagram of the optical system of the die bonder of Fig. 15. FIG. 17 is a configuration diagram of the optical system of the pre-forming part of FIG. 16. Fig. 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 obtaining an inspection image of a paste adhesive. Fig. 20 is a flowchart illustrating the inspection image processing of Fig. 19; FIG. 21 is a flowchart showing a method of manufacturing a semiconductor device.

Claims (16)

A die bonder, comprising: a syringe, which coats a paste-like adhesive on a substrate; a bonding head, which mounts a die on the substrate coated with the adhesive; and a lighting device, which is Installed near the syringe, irradiating light to the imaging target in the first state and the second state; a recognition camera; and a control device that controls the illumination device and the recognition camera, and the control device is configured to: The lighting device is in the first state and the recognition camera captures the state before application of the adhesive on the substrate, and captures the state after application of the adhesive on the substrate, so that the lighting device In the second state, the state before the application of the adhesive on the substrate is captured by the recognition camera, and the state after the application of the adhesive on the substrate is captured to obtain the lighting device The binarized data of the difference between the image taken in the state after application and the image taken in the state before application, taken in the first state, to obtain the image taken in the second state of the lighting device The binary data of the difference between the camera image in the state after coating and the camera image in the state before coating, The binarized data obtained in the first state of the lighting device and the binarized data obtained in the second state are synthesized to obtain the adhesive coating pattern. The die bonder described in claim 1, wherein the substrate is a lead frame plated with metal. Such as the die bonder described in claim 1 or 2, wherein the photographed image is an image obtained by averaging images obtained by multiple times of photographing. The die bonder according to 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. The die bonder according to claim 1 or 2, wherein the control device is configured to switch the wavelength of illuminating light so that the illuminating device is in the first state and the second state. The die bonder according to claim 1 or 2, wherein the lighting device is provided with a plurality of oblique light illuminations with different illumination directions, and the control device is configured to control the turning on and off of the oblique light illumination, so that the lighting device becomes the first One state and the above second state. The die bonder described in claim 6, wherein the above-mentioned oblique light illumination system has different illumination directions in the horizontal direction. The die bonder according to claim 6, wherein the above-mentioned oblique light illumination system has different illumination directions in the vertical direction. The die bonder according to claim 1 or 2, wherein the lighting device includes a plurality of oblique light illuminations with different illumination directions, and the control device is configured to control the movement of the oblique light illumination so that the lighting device is in the first state and The above second state. The die bonder according to claim 1 or 2, wherein the lighting device includes a ring-shaped oblique light illumination having a plurality of areas, and the control device is configured to control lighting and extinguishing of each of the above-mentioned areas of the ring-shaped oblique light. , And the lighting device is brought into the first state and the second state. The die bonder according to claim 1 or 2, wherein the illuminating device is an illuminating device capable of irradiating parallel light and diffused light, and the control device is configured to control the switching of the parallel light and the diffused light to enable the illumination The device is in the first state and the second state. The die bonder according to claim 11, wherein the illumination device has an illumination for illuminating the parallel light and a coaxial illumination for illuminating the diffused light. The die bonder according to claim 1 or 2, wherein the lighting device is provided with a polarizing filter or a wave plate, and the control device is configured to control the presence or rotation of the polarizing filter, or the presence or absence of the wave plate Switching to bring the lighting device into the first state and the second state. A method of manufacturing a semiconductor device includes: (a) a process of loading a wafer ring holder holding a dicing tape to which a die is attached; (b) a process of loading a substrate; (c) a process of picking up the above-mentioned die; (d) ) The process of applying a paste adhesive on the substrate; and (e) the process of bonding the picked-up die to the substrate, the process (d) includes: (d1) making the lighting device the first (D2) The process of switching the lighting device to the second state and capturing the state of the substrate before applying the adhesive in one state; (d3) Switching the lighting device to the first state and imaging the The process of applying the adhesive on the substrate; (d4) the process of switching the lighting device to the second state and photographing the applied state of the adhesive on the substrate; (d5) ) The process of finding the difference between the photographic image of the above-mentioned state after the application of the lighting device in the first state and the photographic image of the state before the application, and obtaining the binary data of the above-mentioned difference; (d6) The process of finding the difference between the photographic image of the state after the application of the lighting device in the second state and the photographic image of the state before the application, and obtaining the binary data of the difference; (d7) Synthesis The process of obtaining the above-mentioned adhesive coating pattern by using the binarized data obtained in the first state of the lighting device and the binarized data obtained in the second state. The method for manufacturing a semiconductor device according to claim 14, wherein the (c) process system places the picked-up die on an intermediate platform, and the (e) process system picks up the die placed on the intermediate platform . The method for manufacturing a semiconductor device according to claim 14, wherein the substrate is a lead frame plated with metal.

Images