Mounting device and semiconductor device manufacturing method

Abstract

To provide a mounting device which can reduce a vibration influence in stroboscope exposure recognition imaging.SOLUTION: A mounting device includes an imaging device which is relatively moved to an imaging object and images the imaging object, and an illumination device which irradiates the imaging object with light. The illumination device is configured to irradiate a first imaging object with stroboscope light a plurality of times within one exposure time of the imaging device when the first imaging object is imaged during operation of operation shafts other than a recognition operation shaft, after stopping of the recognition operation shaft.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present disclosure relates to a mounting apparatus and is applicable to a mounting apparatus that uses, for example, strobe lighting. [Background technology]

[0002] In electronic component mounting devices, in order to mount electronic components with high accuracy, while the electronic component is held by the suction nozzle and moved to the mounting section, the electronic component is imaged by a digital camera having an image sensor such as a CCD or CMOS, the captured image information is converted into an electrical signal, and the image is processed to obtain a measurement value. Then, based on the measurement value, the mounting position of the electronic component is corrected while the electronic component is moving, and the electronic component is mounted on the printed circuit board. In order to obtain a high-precision image with few errors when imaging the electronic component with this camera, it is necessary to use an illumination device with a certain amount of light or more, and generally, a means such as a flashing light from a strobe or continuous lighting from a halogen lamp is used (for example, Patent Document 1). In the case of exposure of a recognition camera using strobe lighting (strobe exposure), the exposure time can be set to a short period of several tens of μs, making it possible to capture images of high-speed movements and perform recognition processing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2000-124683 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a device where multiple axes operate simultaneously, if another axis operates during recognition imaging, the image captured may be misaligned between a stationary position and an image captured while vibrating due to the effects of vibration caused by the operation. Strobe exposure is an electronic circuit configuration that focuses on emitting a high amount of light in a short period of time for high-speed processing, and there is a limit to the maximum emission time for extending the strobe's illumination time, making it difficult to emit light for longer than one cycle of the device's natural vibration (e.g., tens of Hz, tens of ms, etc.) and capture the image. An object of the present disclosure is to provide a mounting device capable of reducing the influence of vibration in strobe exposure recognition imaging. Other objects and novel features will become apparent from the description of this specification and the accompanying drawings. [Means for solving the problem]

[0005] A brief summary of representative aspects of this disclosure is as follows. That is, the mounting apparatus includes an imaging device that moves relative to an imaging target and captures an image of the imaging target, and an illumination device that irradiates the imaging target with light. The illumination device is configured to emit a strobe light multiple times within one exposure time of the imaging device. Effect of the Invention

[0006] According to the above mounting apparatus, the influence of vibrations during strobe exposure can be reduced. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing the configuration of an imaging system according to the first embodiment. [Diagram 2] FIG. 2 is a diagram showing the operation timing when imaging is performed shortly after the axis operation of the imaging system of FIG. 1 is stopped. [Diagram 3] FIG. 3 is a diagram showing light emission timing of the imaging system of FIG. [Figure 4] FIG. 4 is a diagram showing the operation timing when imaging is performed with a recognition waiting time provided from the time when the axial operation of the imaging system in FIG. 1 stops until the recognition starts. [Diagram 5] FIG. 5 is a diagram showing the operation timing when imaging is performed multiple times after the axis operation of the imaging system of FIG. 1 is stopped. [Figure 6] FIG. 6 is a diagram showing the configuration of an imaging system according to the second embodiment. [Figure 7] FIG. 7 is a diagram showing the operation timing of the imaging system of FIG. [Figure 8] FIG. 8 is a diagram showing the light emission timing of the imaging system of FIG. [Figure 9] FIG. 9 is a diagram showing the configuration of an imaging system according to a first modified example. [Figure 10] FIG. 10 is a top view showing an outline of the flip chip bonder of the embodiment. [Figure 11] FIG. 11 is a diagram for explaining the operation of the pickup flip head and the transfer head when viewed from the direction of the arrow A in FIG. [Figure 12] FIG. 12 is a diagram for explaining the operation of the bonding head when viewed from the direction of arrow B in FIG. [Figure 13] FIG. 13 is a schematic cross-sectional view showing a main part of the die supply section of FIG. [Figure 14] FIG. 14(a) is a diagram showing the configuration of an undervision camera, and FIG. 14(b) is a diagram showing the configuration of a bond camera. [Figure 15] FIG. 15 is a diagram showing the configuration of an imaging system for normal exposure. [Figure 16] FIG. 16 is a diagram showing the operation timing of the imaging system of FIG. [Figure 17] FIG. 17 is a diagram for explaining the operation of the bonding head when viewed from the direction of arrow B in FIG. [Figure 18] FIG. 18 shows images from the Bond camera and the Undervision camera. [Figure 19] FIG. 19 is a flow chart showing a bonding method performed by the flip chip bonder of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the embodiments and examples will be described with reference to the drawings. However, in the following description, the same components are given the same reference numerals and repeated description may be omitted. Note that, in order to clarify the description, the drawings may show the width, thickness, shape, etc. of each part in a schematic manner compared to the actual embodiment, but these are merely examples and do not limit the interpretation of the present invention.

[0009] First Embodiment An imaging system using strobe exposure will be described with reference to Figs. 1 to 5. Fig. 1 is a diagram showing the configuration of an imaging system according to a first embodiment. Fig. 2 is a diagram showing the operation timing when imaging is performed shortly after the imaging system of Fig. 1 stops moving along an axis. Fig. 3 is a diagram showing the light emission timing of the imaging system of Fig. 1. Fig. 4 is a diagram showing the operation timing when imaging is performed with a recognition waiting time provided from when the imaging system of Fig. 1 stops moving along an axis until recognition starts. Fig. 5 is a diagram showing the operation timing when imaging is performed multiple times after the imaging system of Fig. 1 stops moving along an axis.

[0010] As shown in FIG. 1, a strobe exposure imaging system 100S includes a controller 101, strobe illumination power supplies 107a and 107b, an illumination device 103, an imaging device 104 having a camera 104a and a lens 104b, and a recognition processing device 105.

[0011] The controller 101 outputs an imaging trigger signal to the camera 104a, and the camera 104a starts exposure upon receiving the imaging trigger signal, and at the same time outputs an illumination trigger signal (strobe trigger) to the strobe illumination power supplies 107a and 107b so that the illumination is turned on at the set light emission delay time from the start of exposure. The strobe illumination power supplies 107a and 107b receive the illumination trigger signal from the camera 104a and supply illumination light emission current to the illumination device 103. The illumination device 103 is composed of a pseudo coaxial illumination 103a and a side illumination 103b, etc. The illumination device 103 has a number of light-emitting diodes aligned in a matrix, and illuminates the workpiece 108 to be imaged with the surface-emitting light source.

[0012] As shown in Fig. 2, the lighting device 103 emits a single light and emits a strobe light after a light emission delay time (Td4) from the imaging trigger signal. The controller 101 inputs the imaging trigger signal to the camera 104a, and after an exposure delay time (Td1), the camera 104a opens the shutter for a set exposure time (Tex1) to expose, and captures an image of the workpiece 108 to be imaged through the lens 104b. After the camera 104a completes imaging (after a transfer wait time (Td2) after the end of exposure), the camera 104a transfers the image data to the recognition processing device 105, and after a completion wait time (Td3), the recognition processing device 105 calculates the amount of positional deviation, etc. based on the image data.

[0013] If the time from when the imaging trigger signal is issued to when the recognition calculation is completed is defined as the recognition time (Tr), Tr is expressed by the following formula. Tr=Td1+Tex1+Td2+Ttr+Td3+Trc Here, Ttr is the image transfer time, and Trc is the recognition calculation time.

[0014] As shown in Figure 3, the exposure time (Tex1), which is the time the camera shutter is open, is Tex1=Td4+Tem+Tm Here, Tem is the light emission time, and Tm is the exposure margin time. The light emission delay time, light emission time, and light emission intensity are variable values, and the exposure margin time is a fixed value, for example, the following value. Light emission time = 5 to 107.4 μs (in 0.2 μs increments) Light emission delay time = 10 to 112.4 μs (in 0.2 μs increments) Exposure time = 5μs (fixed value) Luminous intensity (light amount) = 512 gradations With strobe exposure, the exposure time (Tex1) can be set to an extremely short time such as about 20 μs, and the emission time, which is the effective exposure time, can also be set to an extremely short time such as about 10 μs, making it possible to perform recognition imaging while moving, and thus enabling high-speed recognition. Here, recognition imaging while moving refers to recognition imaging in which the imaging device 104 is stationary and the workpiece 108 to be imaged is moving, in which the imaging device 104 is moving and the workpiece 108 to be imaged is stationary, and in which both the imaging device 104 and the workpiece 108 to be imaged are moving.

[0015] As described above, in a device in which multiple axes operate simultaneously, if another axis operates during recognition imaging, the position of the captured image may shift between a stationary position and an image captured when vibrating due to the effects of operational vibration.

[0016] If an image is captured shortly after the axis stops moving, a recognition error occurs due to vibration. As shown in Figure 2, the average value of the displacement during exposure becomes the recognition position (black circle in Figure 2), and in Figure 2, it is located at a negative displacement, causing a recognition error. In other words, if an image is captured with one strobe light while vibrating, the position may be shifted.

[0017] As shown in Figure 3, by making the effective exposure time, i.e., the light emission time (Tem), longer than the vibration period, the blurring caused by vibration in the captured image is averaged out, making it possible to reduce the effects of vibration. For example, if the light emission time of the strobe is about 10 ms and the vibration period is 10 ms or less (vibration frequency is 100 Hz or more), it is possible to reduce the effects of vibration. However, when exposing or capturing images while moving, the strobe illuminance is increased, so the lighting power output becomes a high current, and the power capacity is insufficient, making it impossible to emit light for long periods of time. If the light emission time is at most about 100 μs and the vibration period is 100 μs or less (vibration frequency is 10 kHz or more), it is possible to reduce the effects of vibration.

[0018] As shown in Fig. 4, it is possible to set a recognition waiting time (Trw) between the time when the axis operation stops and the start of recognition, and wait for the vibration to subside before exposing. This makes it possible to reduce the impact of vibration even if the vibration period is long. However, it is necessary to set the recognition waiting time (Trw) long in consideration of the long vibration period, and recognition takes time.

[0019] As shown in Figure 5, after the axis operation stops, imaging and recognition calculations can be performed multiple times (N times) and then averaged. This makes it possible to reduce the impact of vibration without having to provide a long recognition waiting time. However, the recognition time (Tr2) is slightly less than N times the recognition time (Tr) in Figures 2 and 3, and recognition takes time. In the case of Figure 5, Tr2=N×Tr-(N-1)Td4 Here, N=2.

[0020] In the strobe exposure of the first embodiment described above, light is emitted only once within the exposure time, and therefore, hereinafter, this will be referred to as one-time strobe exposure.

[0021] Second Embodiment The strobe exposure imaging system of the second embodiment will be described with reference to Figs. 6 to 8. Fig. 6 is a diagram showing the configuration of the imaging system of the second embodiment. Fig. 7 is a diagram showing the operation timing of the imaging system of Fig. 6. Fig. 8 is a diagram showing the light emission timing of the imaging system of Fig. 6, Fig. 8(a) shows the case where the light emission intensity is set to 1 / N, and Fig. 8(b) shows the case where the light emission time is set to 1 / N.

[0022] As shown in FIG. 6, the configuration of an imaging system 100 according to the second embodiment is similar to that of the imaging system 100S in FIG.

[0023] As shown in Figures 6 and 7, the controller 101 outputs an imaging trigger signal to the camera 104a. The camera 104a starts exposure after an exposure delay time (Td1) from the imaging trigger signal, and outputs a continuous illumination trigger signal (strobe trigger) to the strobe illumination power supplies 107a and 107b after a set light emission delay time (Td4) from the start of exposure. The strobe illumination power supplies 107a and 107b emit light from the light-emitting diodes of the illumination device 103 with a preset light emission delay time (Td4), light emission time (Tem), light amount (light emission intensity), and light emission period (Tep) from the illumination trigger signal. The camera 104a opens the shutter for the set exposure time (Tex2) to expose, and captures an image of the workpiece 108 to be imaged through the lens 104b. After the camera 104a has completed imaging (after the transfer waiting time (Td2) after the end of exposure), the camera 104a transfers the image data to the recognition processing device 105, and after the completion waiting time (Td3), the recognition processing device 105 calculates the amount of positional deviation, etc. based on the image data. The camera 104a outputs multiple trigger signals in response to the input of one imaging trigger signal.

[0024] The recognition time (Tr3) is expressed by the following formula, similarly to the first embodiment. Tr3 = Td1 + Tex2 + Td2 + Ttr + Td3 + Trc However, the exposure time (Tex2) in the second embodiment is longer than the exposure time (Tex1) in the first embodiment, and therefore the recognition time (Tr3) in the second embodiment is longer than the recognition time (Tr) in the first embodiment by (Tex2-Tex1).

[0025] As shown in FIG. 8, the exposure time (Tex2) is Tex2 = Tem × (N-1) + Td4 + Tem + Tm The light emission period is limited to 10 ms or more due to the current strobe restrictions. For example, Light emission period = 10 ms Light emission delay time = 10μs Light emission time = 50 μs Exposure time = 5μs N=4 Then, Tex2=10ms×(4-1)+10μs+50μs+5μs=30.11ms It becomes.

[0026] The strobe exposure of the second embodiment described above involves multiple flashes within the exposure time, and is therefore hereinafter referred to as strobe multiple exposure.

[0027] In order to prevent overexposure, the total exposure light amount of the strobe multiple exposure of the second embodiment is set to be the same as the light amount of the strobe single exposure of the first embodiment. The light amount of one strobe exposure is adjusted by adjusting the light emission time and light emission intensity. For example, as shown in FIG. 8(a), when the light emission time of one strobe multiple exposure in which light is emitted N times in one exposure time is set to be the same as the light emission time of one strobe single exposure, the light emission intensity of one strobe multiple exposure is set to 1 / N of the light emission intensity of one strobe single exposure. As shown in FIG. 8(b), when the light emission intensity of one strobe multiple exposure in which light is emitted N times in one exposure time is set to be the same as the light emission intensity of one strobe single exposure, the light emission time of one strobe multiple exposure is set to 1 / N. Also, for example, when the light emission time of one strobe multiple exposure is set to 5 times the light emission time of one strobe single exposure, the light emission intensity of one strobe multiple exposure is set to 1 / 5N of the light emission intensity of one strobe single exposure.

[0028] As shown in Figure 7, the strobe is turned on multiple times (four times in this example) within one exposure time. Images from multiple strobe illuminations are multiplexed onto one image, and the vibration components are averaged within one image. To achieve this, the strobe is exposed multiple times at a period that is less than half the vibration period (Top) within the time that the camera shutter is open (exposure time). This makes it possible to reduce recognition errors caused by vibrations due to axial or other axial movements, vibrations due to external disturbances, etc.

[0029] In the second embodiment, the strobe is emitted multiple times during one image capture and averaged by multiple exposures, thereby making it possible to reduce disturbance effects such as vibrations after the motion axis stops and vibration effects caused by the motion of axes other than the recognition target axis. It is also possible to shorten the time it takes for recognition to start after the recognition target motion axis stops. In addition, since only one image capture and data transfer is required, the transfer time and recognition calculation processing time can be shortened, making it possible to achieve faster speeds than capturing an image multiple times with a normal one-time strobe exposure. In addition, the strobe lighting, which can emit light for an extremely short time with sufficient illuminance, shortens the actual exposure time (exposure time while emitting light), making recognition possible during movement.

[0030] <Modification> Below, some representative modified examples of the embodiment are exemplified. In the following description of the modified examples, the same reference numerals as those in the above-mentioned embodiment may be used for parts having the same configuration and function as those described in the above-mentioned embodiment. The description of such parts may be appropriately cited within the scope of technical inconsistency. Furthermore, a part of the above-mentioned embodiment and all or a part of the multiple modified examples may be appropriately applied in a composite manner within the scope of technical inconsistency.

[0031] (First Modification) FIG. 9 is a diagram showing the configuration of an imaging system according to a first modified example.

[0032] In the second embodiment, the trigger signal for performing multiple strobe emissions is generated by the camera 104a, but it may be generated by a pulse generator external to the camera 104a. The camera 104a of the imaging system 100A of the first modification outputs the input imaging trigger signal to the pulse generating circuit 109, and the pulse generating circuit 109 outputs a predetermined number of trigger signals at predetermined intervals based on the input imaging trigger signal.

[0033] (Second Modification) In the second embodiment, when the light emission time of one strobe multiple exposure is set to be the same as the light emission time of one strobe exposure, the light emission intensity of one strobe multiple exposure is set to 1 / N of the light emission intensity of one strobe exposure, but the light emission intensity of one strobe multiple exposure may be set to be the same as the light emission intensity of one strobe exposure. This makes it possible to ensure brightness by exposing the strobe multiple times in appearance inspection for detecting foreign bodies, even when recognizing a dark object for which the illuminance is insufficient with one exposure, and to recognize the object.

[0034] (Third Modification) The imaging system 100S of the first embodiment may be combined with the imaging system 100 of the second embodiment. The imaging system of the third modified example has the strobe single exposure function (strobe single exposure mode) of the imaging system 100S and the strobe multiple exposure function (strobe multiple exposure mode) of the imaging system 100.

[0035] In the imaging system of the third modified example, in a strobe single exposure mode, the camera 104a outputs a single trigger signal based on an imaging trigger signal from the controller 101, and operates similarly to the imaging system 100S. In a strobe multiple exposure mode, the camera 104a outputs continuous trigger signals based on an imaging trigger signal from the controller 101, and operates similarly to the imaging system 100. EXAMPLES

[0036] Hereinafter, an example of application of the above-mentioned embodiment to a flip chip bonder, which is an example of a mounting device, will be described. Note that the flip chip bonder is used for manufacturing a Fan Out Wafer Level Package (FOWLP), which is a package that forms a rewiring layer in a wide area that exceeds the chip area, for example.

[0037] Fig. 10 is a top view showing an outline of the flip chip bonder of the embodiment. Fig. 11 is a diagram explaining the operation of the pickup flip head and the transfer head when viewed from the direction of the arrow A in Fig. 10. Fig. 12 is a diagram explaining the operation of the bonding head when viewed from the direction of the arrow B in Fig. 10. Fig. 13 is a schematic cross-sectional view showing the main part of the die supply unit in Fig. 10. As shown in FIG. 10, the flip chip bonder 10 is roughly divided into a die supply section 1, a first pickup section 2a, a second pickup section 2b, a first transfer stage section 3a, a second transfer stage section 3b, a first bonding section 4a, a second bonding section 4b, a transport section 5, a substrate supply section 6K, a substrate unloading section 6H, and a control device 7 for monitoring and controlling the operation of each section. The second pickup section 2b, the second transfer stage section 3b, and the second bonding section 4b are arranged in mirror symmetry with the first pickup section 2a, the first transfer stage section 3a, and the first bonding section 4a with respect to a line passing through the die D to be picked up and extending in the Y-axis direction, and are configured in the same manner and operate in the same manner. The "b" in the reference numerals of the components of the second pickup section 2b, the second transfer stage section 3b, and the second bonding section 4b corresponds to the "a" in the reference numerals of the components of the first pickup section 2a, the first transfer stage section 3a, and the first bonding section 4a.

[0038] First, the die supply unit 1 supplies a die D to be mounted on a substrate P, which is an example of a workpiece. The die supply unit 1 includes a wafer holder 12 that holds a divided wafer 11, a push-up unit 13 that pushes up the die D from the wafer 11, and a wafer ring supply unit 18. The die supply unit 1 moves in the XY directions by a driving means (not shown), and moves the die D to be picked up to the position of the push-up unit 13. The wafer ring supply unit 18 has a wafer cassette (not shown) in which the wafer ring 14 is stored, and sequentially supplies the wafer ring 14 to the die supply unit 1 and replaces it with a new wafer ring. The wafer cassette in which the wafer ring 14 is stored is supplied to the wafer ring supply unit 18 from outside the flip chip bonder 10. The die supply unit 1 moves the wafer ring 14 to a pick-up point so that the desired die D can be picked up from the wafer ring 14. The wafer ring 14 is a jig to which the wafer 11 is fixed and which can be attached to the die supply unit 1.

[0039] The first pickup unit 2a is located on the substrate supply unit 6K side with respect to the die D to be picked up. The first pickup unit 2a includes a pickup flip head 21a that picks up and inverts the die D, a drive unit 23a that raises and lowers, rotates, inverts, and moves a collet 22a (see FIG. 11) in the X-axis direction, a pickup head 25a having a collet 26a (see FIG. 11) that suctions and holds the die D at its tip, and a drive unit 27a that raises and lowers the pickup head 25a and moves it in the X-axis direction. A wafer recognition camera 24 is provided directly above the die D to be picked up, and is shared by the first pickup unit 2a and the second pickup unit 2b. With this configuration, as shown in FIG. 11, the pickup flip head 21a picks up the die D based on the image data of the wafer recognition camera 24, rotates the pickup flip head 21a 180 degrees, inverts the bumps of the die D to face downward, and sets the die D to a position for handing it over to the pickup head 25a. The pick-up head 25a receives the inverted die D from the pick-up flip head 21a and places it on the first transfer stage portion 3a.

[0040] The first transfer stage unit 3a includes transfer stages 31a1 and 31a2 on which a die D is temporarily placed, an undervision camera (first imaging device) 34a, and an undervision correction mark 35a. The transfer stages 31a1 and 31a2 are movable in the Y-axis direction by a driving unit (not shown).

[0041] The first bonding unit 4a is located on the substrate supply unit 6K side with respect to the die D to be picked up. The first bonding unit 4a picks up the die D from the transfer stages 31a1 and 31a2 and bonds it onto the substrate P that is being transported. The first bonding unit 4a includes a bonding head 41a, a bond head table 45a that moves the bonding head 41a in the Z-axis direction, a gantry table (Y beam) 43a that moves the bond head table 45a in the Y-axis direction, a pair of X beams (not shown) that move the gantry table 43a in the X-axis direction, and a bond camera (second imaging device) 44a that captures an image of a position recognition mark (not shown) on the substrate P and recognizes the bonding position. The gantry table 43a extends in the Y-axis direction so as to straddle the mounting stage BS (see FIG. 12), and both ends of the gantry table 43a are supported by the pair of X beams so as to be movable in the X-axis direction. When the die D is bonded to the substrate P, the substrate P is fixed by suction to the mounting stage BS. The bond camera 44a is provided on a bond head table 45a. As shown in Fig. 12, the bonding head 41a includes bonding heads 41a1, 41a2, 41a3, and 41a4 having collets 42a1, 42a2, 42a3, and 42a4, respectively, which hold four dies D by suction at their tips. With this configuration, the bonding head 41a picks up the die D from the transfer stages 31a1, 31a2, and the undervision camera 34a and the bond camera 44a capture an image of the position where the bonding head holds the die D. Based on this captured image data, a bonding positioning correction position is calculated, and the bonding head is moved to bond the die D to the substrate P.

[0042] The transport section 5 includes transport rails 51, 52 along which the substrate P moves in the X-axis direction. The transport rails 51, 52 are provided in parallel. With this configuration, the substrate P is carried out from the substrate supply section 6K, moves to the bonding position along the transport rails 51, 52, moves to the substrate unloading section 6H after bonding, and delivers the substrate P to the substrate unloading section 6H. While the die D is being bonded to the substrate P, the substrate supply section 6K carries out a new substrate P and waits on the transport rails 51, 52. The substrate P is carried into the substrate supply section 6K from outside the flip chip bonder 10, and the substrate P on which the die D is placed is carried out from the substrate unloading section 6H to outside the flip chip bonder 10.

[0043] The control device 7 includes a storage device (memory) that stores data and programs (software) that monitor and control the operation of each part of the flip chip bonder 10, and a central processing unit (CPU) that executes the programs stored in the memory. The control device 7 includes the controller 101 and the recognition processing device 105 of the embodiment.

[0044] 13, the wafer holder 12 has an expand ring 15 that holds a wafer ring 14, a support ring 17 that horizontally positions a dicing tape 16 held by the wafer ring 14 and having a plurality of dies D adhered thereto, and a push-up unit 13 for pushing up the dies D. To pick up a desired die D, the push-up unit 13 moves up and down by a drive mechanism (not shown), and the die supply unit 1 moves horizontally.

[0045] The configurations of the undervision camera and the bond camera will be described with reference to Fig. 14. Fig. 14(a) is a diagram showing the configuration of the undervision camera, and Fig. 14(b) is a diagram showing the configuration of the bond camera.

[0046] The undervision camera 34a includes an imaging device 344 having a camera body 344a and a lens 344b, and an illumination device 343 having a pseudo coaxial illumination 343a and a ring illumination 343b. The undervision camera 34a is provided facing upward so as to image the die D from directly below. The camera body 344a and the illumination device 343 are controlled in the same manner as the camera body 104a and the illumination device 103 of the imaging system 100 of the embodiment. That is, the undervision camera 34a can image the die D by a single strobe exposure or multiple strobe exposure of the embodiment in response to an instruction from the control device 7. The undervision camera 34b has a similar configuration to the undervision camera 34a.

[0047] The bond camera 44a includes an imaging device 444 having a camera body 444a and a lens 444b, and an illumination device 443 having a pseudo coaxial illumination 443a and a side illumination 443b. The bond camera 44a is provided facing downward so as to image the undervision correction mark 35a, the die D, and the substrate P below from above. The camera body 444a and the illumination device 443 are controlled in the same manner as the camera 104a and the illumination device 103 of the imaging system 100 of the embodiment. That is, the bond camera 44a can image the undervision correction mark 35a, the die D, and the substrate P by the strobe single exposure or the strobe multiple exposure of the embodiment. The bond camera 44b has a similar configuration to the bond camera 44a.

[0048] The wafer recognition camera 24 has a similar configuration to the bond camera 44a, but captures the wafer 11 (die D) by normal exposure. However, like the undervision camera 34a and the bond camera 44a, it can also be replaced with a system capable of strobe exposure or strobe multiple exposure.

[0049] A normal exposure imaging system that uses constant illumination and controls exposure with a camera shutter will be described with reference to Figures 15 and 16. Figure 15 is a diagram showing the configuration of a normal exposure imaging system. Figure 16 is a diagram showing the operation timing of the imaging system in Figure 15.

[0050] The normal exposure imaging system 100R includes a controller 101, illumination power sources 102a and 102b, an illumination device 103, an imaging device 104 having a camera 104a and a lens 104b, and a recognition processing device 105.

[0051] The controller 101 outputs control signals such as lighting ON / OFF and illuminance setting to the lighting power supplies 102a and 102b, and the lighting power supplies 102a and 102b supply lighting current to the lighting device 103. The lighting device 103 is composed of a pseudo-coaxial lighting device 103a and a side lighting device (such as a ring lighting device or a four-way bar lighting device) 103b. The lighting device 103 has a large number of light-emitting diodes aligned in a matrix, and illuminates the workpiece 108 to be imaged with the surface-emitting light source.

[0052] The lighting device 103 is always on or is turned on before recognition exposure. The controller 101 inputs an imaging trigger signal to the camera 104a, and after an exposure delay time (Td1), the camera 104a opens the shutter for the set exposure time (Tex3) to expose, and captures an image of the workpiece 108 to be imaged through the lens 104b. After the camera 104a has completed imaging (after the end of exposure and the transfer wait time (Td2)), the camera 104a transfers the image data to the recognition processing device 105, and the recognition processing device 105 calculates the amount of positional deviation, etc. based on the image data.

[0053] The recognition time (Tr4) is expressed by the following formula, similarly to the first embodiment. Tr4 = Td1 + Tex3 + Td2 + Ttr + Td3 + Trc However, the exposure time (Tex3) is longer than the exposure time (Tex1) in the first embodiment, and therefore the recognition time (Tr3) is longer than the recognition time (Tr) in the first embodiment by (Tex3-Tex1).

[0054] As mentioned above, in a device in which multiple axes operate simultaneously, if another axis operates during recognition imaging, the image captured when the axis is in a stationary position may be misaligned from the image captured when the axis is vibrating due to the effects of vibration caused by the operation. However, as shown in Fig. 16, by lengthening the exposure time, blurring caused by vibration in the captured image can be averaged, making it possible to reduce the effects of vibration. Note that by ensuring an exposure time of 10 ms or more, operational vibrations of 100 Hz or more can be averaged in the image, making it possible to reduce the effects of vibration.

[0055] Next, the undervision correction will be described with reference to Figs. 17 and 18. Fig. 17 is a diagram for explaining the operation of the bonding head when viewed from the direction of the arrow B in Fig. 10, Fig. 17(a) is a diagram showing the state of imaging the first bonding head and the corresponding undervision correction mark, Fig. 17(b) is a diagram showing the state of imaging the second bonding head and the corresponding undervision correction mark, Fig. 17(c) is a diagram showing the state of imaging the third bonding head and the corresponding undervision correction mark, and Fig. 17(d) is a diagram showing the state of imaging the fourth bonding head and the corresponding undervision correction mark. Fig. 18(a) is a diagram showing an image of the undervision correction mark captured by the bond camera, Fig. 18(b) is a diagram showing an image of the die captured by the undervision camera, and Fig. 18(c) is an image of the reference mark on the substrate captured by the bond camera. Note that the captured image in Fig. 18 shows the outer periphery in black and the interior in white for ease of explanation.

[0056] The undervision correction mark 35a is provided on the opposite side of the substrate P across the undervision camera 34a. As shown in FIG. 17, the undervision correction mark 35a is formed by a point light source configured by irradiating pinholes 35a1 to 35a4 of the plate 35a5 with light source 35a6 to 35a9 such as LEDs arranged under the light-shielding plate 35a5. The four pinholes 35a1 to 35a4 are arranged at positions corresponding to the four collets 42a1 to 42a4. Therefore, the four pinholes 35a1 to 35a4 constitute four undervision correction marks. When referring to the four undervision correction marks individually, the reference symbols 35a1 to 35a4 are used.

[0057] When the bond camera 44a captures the undervision correction mark 35a, the light emitted from the illumination device 443 of the bond camera 44a is incident on the undervision camera 34a, and the illumination device 443 of the bond camera 44a is turned off so as not to affect the recognition of the undervision camera 34a. This reduces the effect on the imaging of the collet 42a by the undervision camera 34a, which will be described later.

[0058] While the bonding head 41a and the bond camera 44a move in the Y-axis direction, the bond camera 44a captures and recognizes the undervision correction mark 35a, and as shown in FIG. 18(a), recognizes the deviation between the position of the undervision correction mark 35a initially registered (mark initial position) and the position of the undervision correction mark 35a recognized by the bond camera 44a, and calculates (dXmark, dYmark). When the collet 42a is positioned at the center of the undervision camera 34a, the undervision correction mark 35a is captured by the bond camera, the position is measured, and the mark initial position is registered. At the same time as capturing the undervision correction mark 35a by the bond camera 44a, the undervision camera 34a captures and recognizes the mounting surface of the die D held by suction on the collet 42a, and as shown in FIG. 18(b), recognizes and measures the position of the die D from the center of the undervision camera 34a to calculate (dXdie, dYdie). From the results of (dXmark, dYmark) and (dXdie, dYdie), the position of the die D attracted and held by the collet 42a relative to the position of the undervision correction mark 35a is calculated.

[0059] 17, the die D held by suction on each of the four collets 42a1-42a4 mounted on the bonding head 41a is moved onto the undervision camera 34a, an image of the die D is captured, and the position is recognized. The undervision correction marks 35a1-35a4 corresponding to the positions recognized by the undervision camera 34a for the collets 42a1-42a4 are captured and recognized by the bond camera 44a at the same time that the undervision camera 34a recognizes and captures the die D. This will be described in detail below.

[0060] First, as shown in FIG. 17(a), the die D adsorbed and held on the collet 42a1 of the first bonding head 41a1 is moved above the undervision camera 34a, and the die D is imaged to recognize its position. At the same time, the undervision correction mark 35a1 corresponding to the position recognized by the undervision camera 34a for the die D adsorbed and held on the collet 42a1 is imaged by the bond camera 44a to recognize its position.

[0061] Next, as shown in FIG. 17(b), the die D adsorbed and held by the collet 42a2 of the second bonding head 41a2 is moved above the undervision camera 34a, and the die D is imaged to recognize its position. At the same time, the undervision correction mark 35a2 corresponding to the position recognized by the undervision camera 34a for the die D adsorbed and held by the collet 42a2 is imaged by the bond camera 44a to recognize its position.

[0062] Next, as shown in FIG. 17(c), the die D adsorbed and held by the collet 42a3 of the third bonding head 41a3 is moved above the undervision camera 34a, and the die D is imaged to recognize its position. At the same time, the undervision correction mark 35a3 corresponding to the position recognized by the undervision camera 34a for the die D adsorbed and held by the collet 42a3 is imaged by the bond camera 44a to recognize its position.

[0063] Next, as shown in FIG. 17(d), the die D adsorbed and held by the collet 42a4 of the fourth bonding head 41a4 is moved above the undervision camera 34a, and the die D is imaged to recognize its position. At the same time, the undervision correction mark 35a4 corresponding to the position recognized by the undervision camera 34a for the die D adsorbed and held by the collet 42a4 is imaged by the bond camera 44a to recognize its position.

[0064] After the undervision camera 34a has completed the recognition of the position of the die D, as shown in FIG. 17, the bonding head 41a, while suction-holding the die D, moves to the substrate P that is suction-fixed to the mounting stage BS, and bonds the die D to a predetermined position on the substrate P. At this time, the bond camera 44a captures and recognizes the image of the reference mark RM provided on the substrate P, and recognizes and measures the position of the reference mark RM on the substrate P as viewed from the center of the bond camera 44a as shown in FIG. 18(c), and obtains (dX RM , dY RM) is calculated. When calculating the position for bonding the die D from the position of this reference mark RM, the bond position is calculated by adding the position of the die D attracted and held by the collet 42a to the position of the undervision correction mark 35a obtained earlier. In other words, (Xbond, Ybond) is calculated by subtracting each recognition result from the target positioning coordinates for bonding.

[0065] Xbond=dX RM -dXdie-dXmark Ybond=dY RM -dYdie-dYmark This makes it possible to offset the effects of bonding head positioning errors and deviations in the positioning of the bonding head due to operational vibrations, and to always calculate the position of the die D based on the undervision correction mark 35a as a reference, and to align the bond position from the reference mark RM. In this example, when the head is positioned at the bonding position with each collet, a reference mark RM is placed within the field of view that can be imaged by the bond camera, and the bond position is corrected by recognizing this. However, as a method of correcting the positioning during bonding, the same effect can be obtained by imaging, recognizing, and calculating with the bond camera based on an alignment mark provided in advance on the substrate to be bonded, a mark provided individually at each bonding position on the substrate, or a die that has already been bonded, and correcting the bond position by matching it with the recognition result of the undervision correction mark.

[0066] Next, a bonding method (a method for manufacturing a semiconductor device) performed in the flip chip bonder of the embodiment will be described with reference to FIG. 19. FIG. 19 is a flow chart showing the bonding method performed in the flip chip bonder of the embodiment. The first pickup unit 2a, the first transfer stage unit 3a, and the first bonding unit 4a will be mainly described, but the second pickup unit 2b, the second transfer stage unit 3b, and the second bonding unit 4b are similar. The second pickup unit 2b, the second transfer stage unit 3b, and the second bonding unit 4b operate in parallel to the first pickup unit 2a, the first transfer stage unit 3a, and the first bonding unit 4a within a range that does not interfere with them.

[0067] When manufacturing a semiconductor device with the flip chip bonder 10, a wafer cassette containing wafer rings 14 is supplied to a wafer ring supply section 18 from outside the flip chip bonder 10. In addition, a substrate P is carried into a substrate supply section 6K from outside the flip chip bonder 10. The substrate P on which a die D is mounted is carried out from a substrate carry-out section 6H to the outside of the flip chip bonder 10. The operation inside the flip chip bonder 10 will be described below.

[0068] Step S1: The control device 7 moves the wafer holder 12 so that the die D to be picked up is positioned directly above the push-up unit 13, and positions the die to be peeled relative to the push-up unit 13 and the collet 22a based on the image data of the wafer recognition camera 24. The push-up unit 13 is moved so that the upper surface of the push-up unit 13 contacts the rear surface of the dicing tape 16. At this time, the control device 7 adsorbs the dicing tape 16 to the upper surface of the push-up unit 13. The control device 7 lowers the collet 22a while drawing a vacuum, and lands it on the die D to be peeled, and adsorbs the die D. The control device 7 raises the collet 22a, and peels the die D from the dicing tape 16. As a result, the die D is picked up by the pickup flip head 21a.

[0069] Step S2: The control device 7 moves the pickup flip head 21a.

[0070] Step S3: The control device 7 rotates the pickup flip head 21a 180 degrees to invert the bump surface (front surface) of the die D so that it faces downward, and then inverts the bump surface (front surface) of the die D so that it faces downward, and prepares the die D for handing over to the pickup head 25a.

[0071] Step S4: The control device 7 picks up the die D from the collet 22a of the pickup flip head 21a by the collet 26a of the pickup head 25a, and the die D is delivered.

[0072] Step S5: The control device 7 inverts the pickup flip head 21a so that the suction surface of the collet 22a faces downward.

[0073] Step S6: Before or in parallel with step S5, the control device 7 moves the pickup head 25a to the transfer stage 31a1.

[0074] Step S7: The control device 7 places the die D held by the pickup head 25a on the transfer stage 31a1.

[0075] Step S8: The control device 7 moves the pickup head 25a to a delivery position for the die D. The control device 7 repeats steps S1 to S8 a predetermined number of times (four times in this embodiment).

[0076] Step S9: After or in parallel with step S8, the control device 7 moves the transfer stage 31a1 to a handover position with the bonding head 41a.

[0077] Step SA: The control device 7 images the die D held on the transfer stage 31a1 using the bond camera 44a, and picks up multiple dies D (four in this embodiment) from the transfer stage 31a1 all at once using the collet 42a of the bonding head 41a, and the die D is handed over.

[0078] Step SB: The control device 7 moves the four dies D held by the collets 42a1, 42a2, 42a3, and 42a4 of the bonding heads 41a1, 41a2, 41a3, and 41a4 from the transfer stage 31a1 onto the substrate P. At this time, the undervision correction mark 35a is imaged while the bond camera 44a is moved, and the undervision camera 34a images the four moving dies D. The gantry table 43a moves in the X-axis direction, and the bonding heads 41a move in the Y-axis direction.

[0079] Step SC: The control device 7 images the substrate using the bond camera 44a, and based on the data of the undervision correction mark 35a imaged by the bond camera 44a, the data of the die D imaged by the undervision camera 34a, and the data of the substrate imaged by the bond camera 44a, places the four dies D picked up by the collets 42a1, 42a2, 42a3, and 42a4 of the bonding heads 41a1, 41a2, 41a3, and 41a4 from the transfer stage 31a1 all at once on the substrate P.

[0080] Step SD: The control device 7 moves the bonding heads 41a1, 41a2, 41a3, and 41a4 to the transfer positions with the transfer stage 31a2.

[0081] Step SE: The control device 7 moves the transfer stage 31a1 to a position for delivery to and from the pickup head 25a.

[0082] In the above flow, the transfer stage 31a1 is used as an example, but the same applies when the transfer stage 31a2 is used.

[0083] In the flip chip bonder 10, by using a very short-time light emitting strobe of about 10 μs for imaging the die and substrate, it is possible to improve productivity by exposing and imaging the die and substrate to be imaged while they are moving (recognition by fly scan), but a very short-time single strobe exposure can cause recognition errors due to disturbances such as vibrations, which can hinder high-precision bonding. In such cases, by using multiple strobe exposures as in the example proposed in this invention, the camera is exposed for 10 ms or more and the strobe is emitted multiple times within the exposure time, which reduces recognition errors caused by vibrations during imaging and suppresses deterioration of accuracy due to errors in recognition correction, making it possible to provide high-precision bonding operations.

[0084] The invention made by the present inventors has been specifically described above based on the embodiments and examples. However, it goes without saying that the present invention is not limited to the above embodiments and examples, and various modifications are possible.

[0085] In the embodiment, an example has been described in which the controller 101 outputs an imaging trigger signal to the camera 104a. However, it is also possible that the recognition processing device 105 outputs an exposure start command to the camera 104a, and the camera 104a starts exposure upon receiving the exposure start command, and outputs an illumination trigger signal to the strobe illumination power supplies 107a and 107b.

[0086] In addition, in the embodiments and examples, the illumination device has been described as being configured with a pseudo-coaxial illumination and a ring illumination, but the illumination device may be configured with either one of the pseudo-coaxial illumination and the ring illumination, or another illumination, or a combination of these.

[0087] Further, in the embodiment, an example in which there are four bonding heads (mounting heads) has been described, but the present invention is not limited to this, and there may be one or more bonding heads.

[0088] In addition, in the embodiment, an example has been described in which an inversion mechanism is provided in the pickup flip head, and the transfer head receives the die from the pickup flip head and places it on the intermediate stage, and the intermediate stage is moved; however, this is not limited to this, and the pickup flip head which picks up the die and inverts it may be moved, or the picked-up die D may be placed on a stage unit which can rotate the front and back of the die, and the stage unit may be moved.

[0089] In addition, in the embodiments, an example of application to a flip chip bonder will be described, but the present invention is not limited to this, and can also be applied to a die bonder that bonds a semiconductor chip (die) to a substrate, etc., or a chip mounter (surface mount machine) that mounts a packaged semiconductor device, etc., on a substrate. [Explanation of symbols]

[0090] 100: Imaging system 101: Controller 103: Lighting equipment 104: Imaging device 105: Recognition processing device 107: Strobe lighting power supply 108: Work (image subject)

Claims

1. a first imaging device that moves relative to a first imaging object and captures an image of the first imaging object; A first illumination device that irradiates light onto the first imaging object; A plurality of motion axes including a recognition target motion axis; Equipped with The first lighting device is a mounting device configured to emit a strobe light multiple times within a single exposure time of the first imaging device when the first imaging object is imaged while an axis other than the axis of motion to be recognized is moving after the axis of motion to be recognized has stopped.

2. In the mounting device of claim 1, a strobe lighting power supply for supplying a lighting light emission current to the first lighting device; the first imaging device is configured to initiate exposure based on an imaging trigger signal and generate a strobe trigger signal to be supplied to the strobe illumination power supply; The strobe lighting power supply is configured to periodically supply the lighting light-emitting current to the first lighting device based on the strobe trigger signal.

3. The mounting device of claim 1, further comprising: a strobe lighting power supply for supplying a lighting light emission current to the first lighting device; a pulse generating circuit for generating a strobe trigger signal to be supplied to the strobe lighting power supply based on the trigger signal; Equipped with the first imaging device is configured to initiate exposure based on an imaging trigger signal and generate a strobe trigger signal to be supplied to the strobe illumination power supply; The strobe lighting power supply is configured to periodically supply the lighting light-emitting current to the first lighting device based on the strobe trigger signal.

4. carrying the substrate into a mounting device including a first imaging device for imaging a die, a second imaging device for imaging a substrate, a first illumination device for irradiating light onto the die, a second illumination device for irradiating light onto the substrate, and a mounting head for transporting the die; a first imaging step of imaging the die from below by the first imaging device while the die is being transported by the mounting head; a second imaging step of imaging the substrate from above by the second imaging device; placing the die on the substrate based on the data captured in the first and second imaging steps; Equipped with In the first imaging step, when an image of the die is captured while an axis other than the axis of motion of the recognition target is moving after the axis of motion of the recognition target that moves the first imaging device is stopped, the first illumination device captures an image of the die by emitting a strobe light a plurality of times within one exposure time of the first imaging device; The second imaging process is a method for manufacturing a semiconductor device in which, when the die is imaged while an axis other than the second axis of motion to be recognized is moving after the second imaging device has stopped, the second illumination device emits a strobe multiple times within a single exposure time of the second imaging device to image the substrate.

5. The method of manufacturing a semiconductor device according to claim 4, further comprising: carrying in a wafer ring; a third imaging step of imaging the dies in the wafer ring; Equipped with In the third imaging step, the die is imaged while being constantly illuminated during an exposure time.

Images