TW202422738A - Die bonding device, die bonding method and method for manufacturing semiconductor device - Google Patents

Abstract

The subject of the present invention is to provide a technology that can confirm the presence or absence of transparent die on the dicing tape. The solution is that the die bonding device is equipped with: a dome with adsorption holes for adsorbing the dicing tape with the transparent die attached; an illumination device disposed above the dome; an imaging device disposed above the dome; and a control device. The control device is configured to: When there is no crystal grain above the central portion of the upper surface of the dome, the dicing tape is adsorbed by the adsorption hole to form a recess in the dicing tape, the dicing tape is irradiated with illumination light that emphasizes the brightness difference between the recess and the periphery of the recess by the lighting device, the dicing tape is photographed by the camera to obtain an image, and the presence or absence of a crystal grain is determined based on the image.

Description

Die bonding device, die bonding method and method for manufacturing semiconductor device

The present invention relates to a die bonding device, for example, a die bonding device applicable to picking up a glass chip.

A die bonding device such as a die bonder is a device that uses a bonding material, such as a component to bond (mount and bond) to a substrate or component. The bonding material is, for example, a liquid or film-like resin or solder. The component is, for example, a semiconductor chip, a glass chip, a silicon chip, etc. The semiconductor chip is, for example, a logic chip, a memory chip, an image sensor chip, etc. The substrate is, for example, a wiring substrate or a lead frame formed of a metal sheet, a glass substrate, etc. The semiconductor chip is cut off from the semiconductor wafer with the wafer bonding tape (dicing tape) attached to it and provided to the die bonder. [Prior art literature] [Patent literature]

[Patent Document 1] Japanese Patent Application Publication No. 2010-153874

(The problem that the invention is trying to solve)

Similar to semiconductor chips, glass chips may be cut off from a dicing tape while being attached to a glass wafer (hereinafter also referred to as a "die") and provided to a die bonding machine, and it is necessary to confirm the presence or absence of the die on the dicing tape.

The subject of this case is to provide a technology that can confirm the presence or absence of transparent grains on the dicing tape. Other subjects and novel features can be clearly known from the description and attached figures of this manual. (Means for solving the problem)

If the representative of the present case is briefly described, it is as follows. That is, the die bonding device is provided with: A dome having an adsorption hole for adsorbing a dicing tape with a transparent die attached thereto; An illumination device disposed above the dome; An imaging device disposed above the dome; and A control device, The control device is configured to: When there is no die above the central portion of the upper surface of the dome, the dicing tape is adsorbed through the adsorption hole in order to form a recess in the dicing tape, The illumination device is used to irradiate the dicing tape with illumination light that emphasizes the brightness difference between the recess and the periphery of the recess, The imaging device is used to photograph the dicing tape to obtain an image, and the presence or absence of the die is determined based on the image. [Effect of invention]

According to this case, the presence or absence of transparent grains on the dicing tape can be confirmed.

The following drawings are used to illustrate the embodiments. However, in the following description, the same components are given the same symbols and repeated descriptions are omitted. In addition, in order to make the description clearer, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the actual form. In addition, the relationship between the dimensions of each element and the ratio of each element may not be consistent between multiple drawings.

1 to 4 and 6, the structure of a die bonder according to one embodiment of a semiconductor manufacturing apparatus will be described.

As shown in FIG1 , the die bonding machine 1 generally comprises: a die supply unit 10, a preform unit 90, a bonding unit 40, a conveying unit 50, a substrate supply unit 60, a substrate unloading unit 70, and a control unit (control device) 80. The Y direction is the front-back direction of the die bonding machine 1, and the X direction is the left-right direction. The die supply unit 10 is arranged at the front side of the die bonding machine 1, and the bonding unit 40 is arranged at the rear side. The die supply unit 10 supplies a glass chip D mounted on a substrate S. Here, the substrate S is a semiconductor chip HT mounted in a plurality of product areas that eventually become a package.

As shown in FIG. 2 and FIG. 6 , the die supply unit 10 has: A wafer holding table 12 for holding a wafer W; A lifting unit 13 for lifting a glass chip D from the wafer W; and A wafer identification camera 24. Here, the wafer W is a dicing tape DT that is attached to a disc-shaped glass plate and cut and divided into a plurality of glass chips D. The wafer holding table 12 has: An expanding ring 15 for holding a wafer ring WR; and A horizontal support ring 17 for positioning the dicing tape DT held on the wafer ring WR and having a plurality of glass chips D attached thereto. As shown in FIG6 , the lifting unit 13 has a dome 131 having a plurality of suction holes 132 for sucking the dicing tape DT and a needle 133 for lifting the dicing tape DT. In addition, the suction hole 132 is located under the glass wafer D (adjacent glass wafer Da) adjacent to the target glass wafer Dp in addition to the glass wafer D to be picked up (target glass wafer Dp). The lifting unit 13 is arranged on the inner side of the support ring 17. The control unit 80 moves the wafer holding table 12 in the X-axis direction and the Y-axis direction by means of a wafer stage not shown in the figure, and moves the target glass wafer Dp to the position (pickup position) of the lifting unit 13.

When the target glass wafer Dp is lifted up, the wafer holding stage 12 lowers the retractable ring 15 holding the wafer ring WR. As a result, the dicing tape DT held on the wafer ring WR is stretched, and the distance between the target glass wafer Dp and the adjacent glass wafer Da is expanded. The lifting unit 13 lifts the target glass wafer Dp from the bottom of the target glass wafer Dp, so that the pick-up performance of the target glass wafer Dp is improved.

As shown in FIG3 , the preforming section 90 includes: a syringe 91; a driving section (not shown) for moving the syringe 91 in the X-axis direction, the Y-axis direction, and the vertical direction; and a preforming camera 94 for identifying the application position of the syringe 91. The preforming section 90 applies the paste in a frame shape to the semiconductor chip HT mounted on the substrate S transported by the transport section 50 using the syringe 91. The syringe 91 is sealed with the paste inside, and is configured to apply the paste by squeezing the paste from the front end of the nozzle 92 to the semiconductor chip HT mounted on the substrate S by air pressure.

As shown in FIG4 , the bonding section 40 includes: a bonding head 41, a Y drive section (not shown) and a substrate identification camera 44. The bonding head 41 includes a collet 42 for adsorbing and holding the glass chip D at the front end. The Y drive section moves the bonding head 41 in the Y-axis direction. The substrate identification camera 44 photographs the position identification mark (not shown) of the substrate S to identify the bonding position. The bonding section 40 picks up the glass chip D from the die supply section 10 and bonds it to the semiconductor chip HT coated with the paste PA in a frame shape mounted on the transported substrate S. At this time, the bonding head 41 corrects the pickup position and posture based on the imaging data of the wafer recognition camera 24 and picks up the glass chip D from the wafer W. Then, the bonding head 41 bonds the glass chip D to the semiconductor chip HT mounted on the substrate based on the imaging data of the substrate recognition camera 44.

As shown in FIG1 , the conveying section 50 has a conveying path 52 as a conveying path for the substrate S to move. With such a configuration, the substrate S moves from the substrate supply section 60 along the conveying path 52 to the coating position, moves to the bonding position after coating, and moves to the substrate unloading section 70 after bonding, and the substrate S is delivered to the substrate unloading section 70 .

The control unit 80 includes a memory storing a program (software) for monitoring and controlling the operation of the above-mentioned components of the die bonding machine 1 and a central processing unit (CPU) for executing the program stored in the memory.

Next, a method for manufacturing a semiconductor device using the die bonder of the embodiment will be described with reference to FIG5 . In the following description, the operation of each unit constituting the die bonder 1 is controlled by the control unit 80 .

(Wafer loading process: process S1) The wafer ring WR is supplied to the die bonding machine 1. The supplied wafer ring WR is loaded into the die supply unit 10. Here, the dicing tape DT to which the glass wafers D separated from the wafer W are attached is held on the wafer ring WR.

(Substrate loading process: process S2) The substrate S with the semiconductor chip HT mounted thereon is loaded into the substrate supply unit 60 of the die bonding machine 1. After loading, the substrate S is transferred to the preforming platform 96 by the transfer unit 50.

(Preforming process: process S3) The surface of the semiconductor chip HT mounted on the substrate S before coating is imaged by the preforming camera 94 to confirm the surface to be coated with the paste PA. If there is no problem on the surface to be coated, the position of the substrate S supported by the preforming platform 96 to coat the paste is confirmed and positioned. Positioning is performed by pattern matching, etc., in the same way as the joint 40.

The paste PA is applied from the nozzle 92 at the front end of the syringe 91 to the semiconductor chip HT mounted on the substrate S. The paste PA is, for example, a UV (ultraviolet) curing adhesive. After application, the applied paste PA is photographed by a pre-forming camera 94. Based on the image obtained by the photography, it is confirmed whether the paste PA is correctly applied, and the applied paste PA is inspected (appearance inspection). If there is no problem with the application, the substrate S is transported to the adhesive platform 46 by the transport unit 50.

(Adhesion process: process S4) (Positioning of glass wafer) After process S1, the wafer stage 12 is moved so that the desired glass wafer D can be picked up from the wafer W. The glass wafer D is photographed by the wafer recognition camera 24, and the positioning and surface inspection of the glass wafer D are performed based on the image data obtained by the photography. The image data is processed by image processing, and the deviation (X, Y, θ direction) of the glass wafer D on the wafer holding table 12 from the grain position reference point of the die bonding machine 1 is calculated for positioning. In addition, the grain position reference point is maintained in advance at the predetermined position of the wafer holding table 12 as the initial setting of the device. The surface inspection of the glass wafer D is performed by image processing of the image data.

(Positioning of substrate) After step S3, the substrate S placed on the bonding platform 46 is photographed by the substrate recognition camera 44 to obtain image data. The image data is processed by image processing to calculate the deviation (X, Y, θ direction) of the substrate S from the substrate position reference point of the die bonding machine 1. In addition, the substrate position reference point is a predetermined position of the bonding part 40 that is pre-held as the initial setting of the device.

(Pickup & Adhesion) The adhesive head 41 is moved parallel and lowered to the top of the glass wafer D to be picked up, and the adsorption position of the adhesive head 41 is corrected based on the calculated deviation of the glass wafer D, and the glass wafer D is vacuum-adsorbed by the chuck 42. The adhesive head 41 that has adsorbed the glass wafer D from the wafer W is used to adhere the glass wafer D to a predetermined position of the semiconductor wafer HT of the substrate S mounted on the adhesive platform 46. The glass wafer D adhered to the semiconductor wafer HT is photographed by the substrate recognition camera 44, and the image data obtained by the photography is used to check whether the glass wafer D is adhered to the desired position.

(Substrate unloading process: process S5) The substrate S with the glass wafer D bonded thereto is transported to the substrate unloading unit 70. The substrate S with the glass wafer D bonded thereto is taken out from the substrate unloading unit 70. The substrate S is unloaded from the die bonding machine 1.

In order to clarify this embodiment, the problem of confirming the presence or absence of the glass wafer D is described using Figures 7 and 8. Figure 7 is a schematic diagram showing the state of the illumination light when there is a glass wafer on the dicing tape. Figure 8 is a schematic diagram showing the state of the illumination light when there is no glass wafer on the dicing tape.

As shown in FIG. 7 , in the visible light region, the surface of the transparent glass wafer D generates surface diffuse reflection light DRL due to slight diffuse reflection of the incident light IL and mirror reflection light SRL due to a certain degree of mirror reflection. Furthermore, the interior of the glass wafer D generates transmitted light TRL and internal scattered light SCL due to slight scattering. The interface between the bottom surface of the glass wafer D and the top surface of the dicing tape DT generates surface diffuse reflection light DRL’ due to slight diffuse reflection of the transmitted light TRL and mirror reflection light SRL’ due to a certain degree of mirror reflection. The mirror reflection light SRL’ is transmitted through the glass wafer D and output to the outside of the glass wafer D.

Furthermore, in the visible light region, the transparent dicing tape DT also has properties similar to those of the glass chip D, and the reflectivity, transmittance, and diffusion rate of the dicing tape DT are close to those of the glass chip D. Therefore, the interior of the dicing tape DT generates transmitted light TRL’ and internal scattered light SCL’ due to slight scattering. The bottom surface of the dicing tape DT generates surface diffused reflected light DRL” due to slight diffuse reflection of the transmitted light TRL’ and mirror reflected light SRL” due to a certain degree of mirror reflection. The mirror reflected light SRL” passes through the dicing tape DT and the glass chip D and is output to the outside of the glass chip D. The camera photographs the mirror reflected light SRL, mirror reflected light SRL’, and mirror reflected light SRL”.

As shown in FIG8 , the surface of the dicing tape DT generates surface diffuse reflection light DRL due to slight diffuse reflection of the incident light IL and mirror reflection light SRL due to a certain degree of mirror reflection. Furthermore, the inside of the dicing tape DT generates transmitted light TRL and internal scattered light SCL due to slight scattering. The bottom surface of the dicing tape DT generates surface diffuse reflection light DRL’ due to slight diffuse reflection of the transmitted light TRL and mirror reflection light SRL’ due to a certain degree of mirror reflection. The mirror reflection light SRL’ is output to the outside of the glass chip D through the glass chip D. The camera photographs the mirror reflection light SRL and the mirror reflection light SRL’.

Thus, the difference between the case of a glass chip on a dicing tape and the case of a glass chip on no dicing tape is that the light contains only the mirror-reflected light SRL', and since the mirror-reflected light SRL' is a light amount of light, it is difficult to identify the difference between the two. It is difficult to confirm the presence or absence of one of the two layers forming a layer structure as parallel planes.

Therefore, in coaxial illumination, the mirror reflection light on the surface becomes the same on the glass wafer D and the dicing tape DT, making it difficult to distinguish. In addition, in oblique illumination, the dome 131 of the top unit 13 below is also visible, making it difficult to distinguish. Moreover, in dome illumination, it is a mixture of coaxial illumination and oblique illumination, so there is almost no difference, and the result is difficult to distinguish.

In addition, by changing the wavelength, polarization or incident angle of the material through the reflectivity, transmittance or diffusion rate, it is possible to make a certain degree of change, but in the case of a transparent body that is originally in the visible light region, it is difficult to make a clear difference even if the visible light region is limited or selected.

The above-mentioned problem is solved in the die supply unit 10 of the present embodiment. First, the optical system of the die supply unit 10 will be described using Fig. 9. Fig. 9 is a diagram showing a wafer recognition camera, a lens, a dome, and a photographed object.

A dicing tape DT with a glass wafer D attached is arranged on the dome 131, and a wafer identification camera 24 is provided above the glass wafer D. An illumination device 25 is arranged between the wafer identification camera 24 and the glass wafer D. The illumination device 25 has a surface emitting illumination (light source) 251 and a semi-transparent reflector (semi-transparent mirror) 252 inside. The irradiation light from the surface emitting illumination 251 is reflected by the semi-transparent reflector 252 with the same optical axis as the wafer identification camera 24, and is irradiated to the glass wafer D as parallel light of direct incidence. The illumination device 25 is a coaxial illumination in the lens barrel. The surface emitting illumination 251 is a surface emitting type LED (Light Emitting Diode) light source.

The method for confirming the presence or absence of a glass wafer D is described using FIGS. 10 to 13 and 25. FIG. 10 is a diagram showing a state in which an adsorption operation is performed when a glass wafer is present. FIG. 11 is a diagram showing a state in which an adsorption operation is performed when no glass wafer is present. FIG. 12 is a diagram schematically showing an image taken when a glass wafer is present. FIG. 13 is a diagram schematically showing an image taken when no object glass wafer is present. FIG. 25 is a diagram schematically showing an image taken when no object glass wafer and an adjacent glass wafer are present.

If the adsorption operation is performed with the glass wafer D on the dome 131, as shown in FIG10 , the upper surface of the dicing tape DT is held by the glass wafer D, and thus maintains a flat surface. In contrast, if the adsorption operation is performed without the glass wafer D on the dome 131, as shown in FIG11 , a mortar-like depression is generated at the position of the adsorption hole 132 because the dicing tape DT is soft.

If, for example, parallel light PL of direct lead is used as coaxial illumination in this state, the surface (upper side) of the glass wafer D reflects the mirror reflection light SRL directly upward as shown in Fig. 10. In contrast, on the inclined surface of the portion that is recessed by the adsorption of the dicing tape DT, as shown in Fig. 11, the mirror reflection light SRL is not reflected directly upward, and if the wafer recognition camera 24 set directly above is used to take a picture, it can be seen that the difference from the case where the glass wafer D is present is known.

That is, for example, in the case where there is no target glass wafer Dp, as shown in FIG13, the mirror reflection light SRL of the concave portion does not reach the wafer identification camera 24, so only the area of the adsorption hole 132 becomes dark. However, the mirror reflection light SRL of the bottom portion of the concave portion will be directed toward the wafer identification camera 24, so it appears bright. In contrast, in the case where there is a glass wafer D, as shown in FIG12, the area of the adsorption hole 132 is difficult to distinguish from other areas. In this state, by measuring the brightness of the area (central area) where the target glass wafer Dp should be, the presence or absence of the glass wafer D can be determined by image processing. In addition, the adjacent glass wafer Da is located in the same field of view of the wafer recognition camera 24 as the target glass wafer Dp. Therefore, for example, as shown in FIG. 25, when the target glass wafer Dp is not adjacent to the adjacent glass wafer Da on the left side of the figure, the area of the adsorption hole 132 becomes dark, similarly to the case where there is no target glass wafer Dp. Therefore, the presence or absence of not only the target glass wafer Dp but also the adjacent glass wafer Da can be determined. When it is determined that there is no glass wafer D, the pickup at the position where there is no glass wafer D can be skipped.

Several examples of methods for image processing of an area of a glass wafer to be picked up in order to confirm the presence or absence of the glass wafer D will be described.

(Method 1) Predetermine the area of the adsorption hole 132 and check the change in the average brightness of the area. Set a critical value, and if there is a change above a certain level, it is determined that there is no glass wafer D.

(Method 2) Measure the difference between the maximum and minimum brightness of the area where the glass wafer D should be. If the difference exceeds a predetermined value, it is determined that the glass wafer D is absent.

(Method 3) The pattern of the adsorption hole 132 produced when there is no glass wafer D or when there is a glass wafer D is registered in the model, and the presence or absence of changes is confirmed by using normalized correlation matching, etc.

(Method 4) Obtain a histogram with the brightness of the area where the glass chip D should be located as an index. Since the brightness of the needle-shaped object 133 is large and the brightness of the adsorption hole 132 is small, when there are two peaks in the frequency of brightness, it is determined that there is no glass chip D.

The details of the bonding step (step S4) will be described using Fig. 14. Fig. 14 is a flow chart showing a part of the bonding step.

(Wafer stage pitch movement: step S41) The wafer stage pitch movement in which the wafer holding stage 12 is moved is performed so that the desired glass wafer D can be picked up from the wafer W. As shown in FIG. 6 , the glass wafer D is arranged at the center of the dome 131 of the lifting unit 13.

(Dome adsorption: step S42) The dome 131 moves upward until it contacts the cutting tape DT, and the cutting tape DT is adsorbed by the adsorption hole 132 provided in the dome 131.

(Confirmation of the presence of glass wafer: step S43) The dome 131 and its periphery as shown in FIG6 are photographed by the wafer identification camera 24 and the lighting device 25 disposed above the dome 131 to confirm the presence of the glass wafer D. The method of confirming the presence of the glass wafer D will be described later. If there is no glass wafer D, return to step S41. If there is a glass wafer D, move to step S44.

(Glass wafer positioning: step S44) Using the wafer recognition camera 24 and the lighting device 25, the dome 131 and its surroundings as shown in FIG6 are photographed, and the glass wafer D is positioned using the image of the cutting groove DG. In addition, step S44 can also be performed before step S43.

(Pick up: Step S45) In Step S45, pick up the glass wafer D as described above. Then, return to Step S41.

In the surface inspection of the glass wafer D in step S4, the presence of the glass wafer D is checked. The presence of the glass wafer D is checked to avoid the following problems.

If the glass wafer D on the dicing tape DT disappears for some reason and is not detected during pickup, the arrival sensor of the adhesive head 41 cannot detect the arrival, thus causing an error. The arrival sensor cannot detect the arrival because if the contact surface of the chuck 42 touches the dicing tape DT, scratches or dirt will adhere to the surface of the chuck 42, and the cleanliness of the product cannot be guaranteed. Therefore, the arrival sensor is not used. If an error occurs, the absence of the glass wafer D is not detected until after the pickup process starts, which is inefficient and reduces the productivity of the device. In the worst case, the contact surface of the chuck 42 may touch the dicing tape DT. Therefore, as mentioned above, there is a possibility that the cleanliness of the product cannot be guaranteed.

In the embodiment, the adsorption operation is performed in such a way that the parallelism between the glass wafer D and the surface of the dicing tape DT is lost. Thus, if the predetermined conditions are met by lighting, the direction of the reflection surface will be different even with the same lighting, so the presence or absence of the glass wafer D can be confirmed. The predetermined condition of the embodiment is to irradiate the glass wafer D with parallel light of direct incidence by coaxial lighting.

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

(a) The presence or absence of glass wafers can be determined.

(b) By confirming the presence of a glass wafer before picking up, picking errors can be reduced, thereby improving production efficiency.

(c) The possibility of the chuck accidentally contacting the cut tape surface can be reduced. This can keep the contact surface of the chuck clean and ensure the cleanliness of the product.

(d) When a parallel light source is used as coaxial incident illumination to illuminate the glass wafer, the outline of the glass wafer can be clearly visualized.

(e) Since the presence of the glass wafer can be checked and positioned using the same illumination, the presence check and positioning image processing can be shared in one imaging process, which can prevent the device production takt time from being reduced. This can improve productivity.

(f) The yield rate of products assembled by the die bonding machine can be improved.

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

If the lighting meets the predetermined conditions, the presence or absence of the glass wafer can be determined. However, (1) dome lighting, (2) coaxial lighting with diffuse light emitting from the irradiated surface, and (3) oblique lighting do not meet the predetermined conditions.

The above (1) and (2) are good at uniformly photographing the surface with unevenness, so the intensity of the unevenness caused by adsorption is uniformly restored, so the difference becomes small. The above (3) is originally dominated by the transmitted light, so the surface of the dome 131 can be seen.

To achieve this, it is necessary not only to adsorb but also to irradiate with appropriate lighting. Here are a few examples.

(First variant) Fig. 15 is a diagram showing a wafer identification camera, an illumination device, a dome, and a photographed object of the first variant. Fig. 16 is a diagram schematically showing an image photographed in a state where there is an object glass wafer. Fig. 17 is a diagram schematically showing an image photographed in a state where there is no object glass wafer.

In the embodiment, an example of coaxial illumination using parallel light of direct incidence is described as a lighting device, but coaxial illumination using a point light source may also be used.

The lighting device 25 of the first modification is a coaxial lighting device having a point light source 253 with a reduced light-emitting surface and a semi-transparent reflector 252. The light-emitting surface is set to a size of several mm or less. If the point light source 253 is limited to a small area, it shows a property similar to a parallel light source, so as shown in FIG17, in a state without an object glass wafer Dp, the surface unevenness of the dicing tape DT can be emphasized. In addition, as shown in FIG16, in a state with an object glass wafer Dp, the surface unevenness of the dicing tape DT is not emphasized.

(Second variant) Fig. 18 is a diagram showing a wafer identification camera, an illumination device, a dome, and an object of the second variant. Fig. 19 is a diagram showing a state where an adsorption operation is performed without a glass wafer. Fig. 20 is a diagram schematically showing an image photographed with a glass wafer. Fig. 21 is a diagram schematically showing an image photographed without an object glass wafer.

In the embodiment, the example of coaxial illumination of parallel light of direct incidence is described as the illumination device, but oblique light illumination may also be used. The illumination device 25 of the second modification is an oblique light strip illumination provided near the wafer identification camera 24.

Although it depends on the angle (θ) formed by the depression (recess) of the cutting tape DT, as long as the incident angle of the lighting device 25 is within the range where the mirror-reflected light SRL reflected on the surface of the depression faces the wafer identification camera 24 directly above, a part of the depression can be photographed brightly. Here, the incident angle is the angle of the wafer identification camera 24 relative to the optical axis. At this time, the other area A that becomes a plane appears dark because the mirror-reflected light SRL is not facing the wafer identification camera 24 directly above. The mirror-reflected light SRL of the inclined surface B will enter the wafer identification camera 24. The incident angle of light that meets the conditions is up to twice (2θ) of θ represented by the circular arrow shown in Figure 19. As shown in FIG18, the lighting device 25 is installed within the range. In other words, the lighting device 25 is located within an angle of 2 times a predetermined angle (θ) relative to the optical axis of the wafer recognition camera 24 as viewed from the intersection of the dicing tape DT. Here, 2θ is about 10 to 15 degrees as the upper limit.

As shown in Fig. 21, in a state without the target glass wafer Dp, the surface irregularities of the dicing tape DT can be emphasized. On the other hand, as shown in Fig. 20, in a state with the glass wafer D, the surface irregularities of the dicing tape DT are not emphasized.

(Third variant) Figure 22 is a diagram showing a wafer identification camera, an illumination device, a dome, and a subject of the third variant.

In the embodiment, an example of coaxial illumination of parallel light of direct incident lead is described as an illumination device, but coaxial illumination with an asymmetric illumination area can also be used. The illumination device 25 of the third variant has a surface-emitting illumination (light source) 251, a semi-transparent reflector 252, and a shading plate 254. The illumination device 25 is a coaxial illumination of diffuse light of the type of illuminating surface light. Since the illumination light is reflected by the semi-transparent reflector 252, it can be regarded as having the surface-emitting illumination 251 and the shading plate 254 at the position shown by the dotted line.

The difference in the direction of the concave inclined surface is utilized in the same manner as in the second variant. The irradiation area of the surface illumination 251 is set to be asymmetric with respect to the optical axis of the wafer identification camera 24 within the range of ±2θ. For example, by setting a light shielding plate 254 within the range of the incident angle of ±2θ, a part of the concave inclined surface can be made bright and a part can be made dark.

In addition, the surface lighting 251 may be formed by LEDs arranged in an array, and the illuminated area may be set to be asymmetric by turning the LEDs on and off, or the surface lighting 251 may be formed by a liquid crystal display device, and the illuminated area may be set to be asymmetric by turning the LEDs on and off. Furthermore, the shading plate 254 or the extinguished area of the surface lighting does not necessarily have to be completely irradiated with illumination light, as long as the illumination is darker than the area without the shading plate 254 or the illuminated area of the surface lighting. For example, the shading plate 254 may be formed by a translucent component or a plate with slits. The brightness of the extinguished area of the surface lighting may also be set to be smaller than the brightness of the illuminated area of the surface lighting.

(Fourth variant) FIG. 23 is a diagram showing a wafer identification camera, an illumination device, a dome, and a subject of the fourth variant.

The shading plate 254 of the third variant is to make the symmetry of the irradiation area lose, so the shading plate can also be set below the semi-transparent reflective mirror as long as it does not affect the range of the camera's field of view. The shading plate 255 of the fourth variant is the lower part or below the lighting device 25, and is set within the range of ±2θ with respect to the optical axis of the wafer identification camera 24. The shading plate 255 is composed of a semi-transparent member or a plate with a slit like the shading plate 254.

(Fifth variant) FIG. 24 is a diagram showing a wafer identification camera, an illumination device, a dome, and a subject of the fifth variant.

In the fourth modification, the example of setting the shading plate 255 at the lower part or below the lighting device 25 is described, but an obstacle can also be set below the lighting device. Therefore, it is also possible to replace the shading plate with other drivable units such as the adhesive head or the pickup head to temporarily realize the task of the shading plate.

In particular, the pickup head is usually retracted to a position that does not affect the illumination, but by moving this retracted position closer to the optical axis, the waiting position is symmetrical to the illumination area without illumination, and the effect can be achieved. In this way, visualization can be achieved by simply changing the operation sequence or retracted position without adding new hardware to the existing die bonding machine.

As mentioned above, what is disclosed by the authors of this case is specifically described according to the implementation form, but this case is not limited to the above-mentioned implementation form, and various modifications are possible.

For example, the embodiment describes an example in which a mortar-shaped depression is generated in the dicing tape DT by the adsorption action of the adsorption hole 132 of the dome 131. In addition to adsorption, the dicing tape DT can also be made uneven by weakening the tensile force of the dicing tape DT held on the wafer ring WR.

Furthermore, the embodiment explains the determination of the presence or absence of the adjacent glass chip Dp, but in the variant example, the adjacent glass chip Da and the target glass chip Dp are located in the same field of view of the wafer identification camera 24, so not only the target glass chip Dp but also the presence or absence of the adjacent glass chip Da can be determined.

1: Die bonding machine (die bonding device) 131: Dome 132: Adsorption hole 24: Wafer recognition camera (camera) 25: Lighting device 80: Control unit (control device) D: Glass wafer (die) DT: Dicing tape

[FIG. 1] is a schematic top view of a die bonder of an embodiment. [FIG. 2] is a schematic cross-sectional view of a die supply unit shown in FIG. 1. [FIG. 3] is a schematic side view of a preform unit shown in FIG. 1. [FIG. 4] is a schematic side view of a die supply unit and a bonding unit shown in FIG. 1. [FIG. 5] is a flow chart of a method for manufacturing a semiconductor device using the die bonder shown in FIG. 1. [FIG. 6] is a top view of a lift-up unit shown in FIG. 2 and a glass wafer attached to a dicing tape. [FIG. 7] is a schematic diagram showing the state of illumination light when a glass wafer is on a dicing tape. [FIG. 8] is a schematic diagram showing the state of illumination light when there is no glass wafer on a dicing tape. [FIG. 9] is a diagram showing a wafer recognition camera, a lens, a dome, and a subject. [FIG. 10] is a diagram showing a state in which the adsorption action is performed when there is a glass wafer. [FIG. 11] is a diagram showing a state in which the adsorption action is performed when there is no glass wafer. [FIG. 12] is a diagram schematically showing an image photographed when there is a glass wafer. [FIG. 13] is a diagram schematically showing an image photographed when there is no glass wafer in the object. [FIG. 14] is a flowchart showing a part of the bonding process. [FIG. 15] is a diagram showing a wafer identification camera, an illumination device, a dome, and an object of the first variant. [FIG. 16] is a diagram schematically showing an image photographed in a state in which there is a glass wafer. [FIG. 17] is a diagram schematically showing an image photographed in a state in which there is no glass wafer. [FIG. 18] is a diagram showing a wafer identification camera, an illumination device, a dome, and an object of the second variant. [FIG. 19] is a diagram showing a state in which an adsorption operation is performed when there is no glass wafer. [FIG. 20] is a diagram schematically showing an image photographed in a state in which there is a glass wafer. [FIG. 21] is a diagram schematically showing an image photographed in a state in which there is no object glass wafer. [FIG. 22] is a diagram showing a wafer identification camera, an illumination device, a dome, and an object of the third variant. [FIG. 23] is a diagram showing a wafer identification camera, an illumination device, a dome, and an object of the fourth variant. [Fig. 24] is a diagram showing a wafer identification camera, an illumination device, a dome, and a photographed object of the fifth variant. [Fig. 25] is a diagram schematically showing an image photographed in the case of a non-object glass wafer and one adjacent glass wafer.

24: Wafer identification camera (camera)

25: Lighting equipment

131: Dome

251: Luminous lighting

252: Semi-transparent mirror

D: Glass wafer (crystal)

DT: cutting tape

Claims (11)

A die bonding device comprises: a dome having an adsorption hole for adsorbing a dicing tape with a transparent die attached thereto; an illumination device disposed above the dome; an imaging device disposed above the dome; and a control device, wherein the control device is configured to: when there is no die above the central portion of the upper surface of the dome, adsorb the dicing tape through the adsorption hole in order to form a recess in the dicing tape, irradiate the dicing tape with illumination light that emphasizes the brightness difference between the recess and the periphery of the recess, photograph the dicing tape with the imaging device to obtain an image, and determine the presence or absence of a die based on the image. A die bonding device as claimed in claim 1, wherein the lighting device is a coaxial lighting device that irradiates parallel light. A die bonding device as claimed in claim 1, wherein the lighting device is a coaxial lighting device having a point light source and a semi-transparent mirror illuminated by the point light source. As in claim 1, the die bonding device, wherein the lighting device is oblique lighting at an angle within 2 times of a predetermined angle with respect to the optical axis, as viewed from the intersection of the optical axis of the camera device and the dicing tape, and the predetermined angle is the angle between the upper surface and the concave portion. The die bonding device of claim 1, wherein the lighting device is a coaxial lighting device having a surface lighting device and a semi-transparent mirror illuminated by the surface lighting device, From the intersection of the optical axis of the camera device and the dicing tape, a portion of the optical axis within 2 times of a predetermined angle is not illuminated by the illumination light, The predetermined angle is the angle between the upper surface and the concave portion. A die bonding device as claimed in claim 5, wherein the lighting device comprises a shading plate for shielding a portion of the lighting light between the surface lighting and the semi-transparent mirror. As in claim 5, the die bonding device, wherein the surface lighting is composed of a plurality of LEDs or liquid crystal display devices arranged in an array. As in claim 5, the die bonding device further comprises a shading plate at the bottom or below the aforementioned lighting device, and a portion of the lighting light of the aforementioned lighting device is shielded by the aforementioned shading plate. As in claim 5, the die bonding device further comprises a head, and a portion of the illumination light of the aforementioned illumination device is shielded by the aforementioned head. A die bonding method comprises: a loading step, in which a wafer ring holding a dicing tape with a transparent die attached thereto is loaded into a die bonding device, the die bonding device comprising: a dome having an upper surface and a suction hole provided on the upper surface, a lighting device provided above the dome, and a camera provided above the dome; and a bonding step, in which the die is picked up from the wafer ring and bonded to a substrate, the bonding step being before the die is picked up, comprising: a step of adsorbing the dicing tape through the suction hole in order to form a recess in the dicing tape when there is no die above the central portion of the upper surface of the dome; a step of irradiating the dicing tape with illumination light for emphasizing the brightness difference between the recess and the periphery of the recess by the lighting device; The process of photographing the dicing tape by the photographing device to obtain an image; and the process of determining the presence or absence of a die based on the image. A method for manufacturing a semiconductor device comprises: a loading step, in which a wafer ring holding a dicing tape with a transparent die attached thereto is loaded into a die bonding device, the die bonding device comprising: a dome having an upper surface and a suction hole provided on the upper surface, a lighting device provided above the dome, and a camera provided above the dome; and a bonding step, in which the die is picked up from the wafer ring and bonded to a semiconductor chip bonded to a substrate, the bonding step is before picking up the die, and comprises: a step of adsorbing the dicing tape through the suction hole in order to form a recess in the dicing tape when there is no die above the central portion of the upper surface of the dome; The process of irradiating the dicing tape with illumination light that emphasizes the brightness difference between the concave portion and the periphery of the concave portion by the illumination device; The process of photographing the dicing tape by the imaging device to obtain an image; and The process of determining the presence or absence of a grain based on the image.

Images