Semiconductor manufacturing apparatus and method for manufacturing semiconductor device

Abstract

To provide a technique capable of obtaining a stable bonding strength of wire bonding even in a large semiconductor device.SOLUTION: A semiconductor device 1 includes a receiving table 8 to arrange a lead frame 9 on a top face of the receiving table, and a fixing jig 7 arranged on an upper side of the receiving table 8 to fix the lead frame 9 with the receiving table 8 and the fixing jig. The fixing jig 7 has: a body 7a to hold a top face of the lead frame 9; an opening 7b to expose a wire bonding area where wire bonding in the lead frame 9 is performed; and a lead frame presser 15 to press the wire bonding area of the lead frame 9 to a receiving table 8 side in the opening 7b.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a semiconductor manufacturing apparatus and a method for manufacturing a semiconductor device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there is a semiconductor device in which a conductive lead frame on which a semiconductor element is mounted is sealed in an insulating resin.

[0003] For example, Patent Document 1 discloses a wire bonding device for a lead frame of a small-capacity (compact) semiconductor device. In the technology described in Patent Document 1, during wire bonding, the lead frame is fixed by a bonding table and a lead presser arranged to face the bonding table. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 4-340238 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when wire bonding is performed on a large-capacity (large) semiconductor device, the lead frame also becomes large, and the technology described in Patent Document 1 is unable to firmly fix the lead frame because the size of the lead clamp is small compared to the size of the lead frame.

[0006] Therefore, with the technique described in Patent Document 1, there is a concern that the ultrasonic vibrations during wire bonding may not be properly transmitted to the lead frame, resulting in unstable bonding strength of the wire bonding.

[0007] Therefore, an object of the present disclosure is to provide a technique that makes it possible to obtain stable bonding strength of wire bonding even in the case of a large-capacity semiconductor device. [Means for solving the problem]

[0008] A semiconductor manufacturing apparatus according to the present disclosure includes a receiving table for placing a lead frame on an upper surface thereof, a fixing jig that is arranged above the receiving table and fixes the lead frame with the receiving table, a first table that holds an outer periphery of the fixing jig, and Opening the fixing jig includes an image processing camera that detects first position information indicating the position of the lead frame through a nozzle, a first ball screw attached to the first table, a first motor that moves the fixing jig laterally together with the first table by rotating the first ball screw, and a control unit that controls the drive of the first motor based on the first position information detected by the image processing camera, and the fixing jig includes a main body that holds an upper surface of the lead frame and exposes a wire bonding area in which wire bonding is performed on the lead frame. The above The lead frame has an opening and a lead frame presser for pressing the wire bonding area of ​​the lead frame toward the receiving base in the opening. Effect of the Invention

[0009] According to the present disclosure, even in the case of a large-capacity semiconductor device, the wire bonding area of ​​the lead frame can be firmly fixed by the lead frame holder of the fixing jig, which allows the ultrasonic vibration during wire bonding to be properly transmitted to the lead frame, thereby achieving stable bonding strength of the wire bonding. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic diagram showing an entire semiconductor manufacturing apparatus according to an embodiment; [Diagram 2] 1 is a top view showing a main part of a semiconductor manufacturing apparatus according to an embodiment; [Diagram 3] 1 is a side view showing a main part of a semiconductor manufacturing apparatus according to an embodiment; [Figure 4] 1 is a top view showing a state in which a fixing jig and a first XY table are omitted from a main part of a semiconductor manufacturing apparatus according to an embodiment. [Diagram 5] 1 is a side view showing a state in which a fixing jig and a first XY table are omitted from a main part of a semiconductor manufacturing apparatus according to an embodiment. [Figure 6] FIG. 13 is a top view showing another example of the receiving stand. [Figure 7] 13 is a cross-sectional view showing a state in which a lead frame is placed on another example of the receiving stand. FIG. [Figure 8] FIG. 13 is a top view showing still another example of the receiving stand. [Figure 9] 13A and 13B are diagrams showing the display on the monitor screen when adjusting the position of a fixing jig. [Figure 10] 4 is a flowchart showing a method for manufacturing a semiconductor device using the semiconductor manufacturing apparatus according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] <Embodiment Mode> <Configuration of semiconductor manufacturing equipment> DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described with reference to the accompanying drawings, in which: Fig. 1 is a schematic diagram showing an entire semiconductor manufacturing apparatus 1 according to an embodiment of the present invention.

[0012] 1, the semiconductor manufacturing equipment 1 includes a housing 1a, a receiving stand 8, a fixing jig 7, a transport rail 6, a bonding head 4, a monitor 5, a loader 2, and an unloader 3. The semiconductor manufacturing equipment 1 is capable of performing wire bonding on small-capacity (compact) semiconductor devices and large-capacity (large) semiconductor devices.

[0013] The housing 1a accommodates a plate-shaped receiving stand 8, a plate-shaped fixing jig 7, a transport rail 6, and a bonding head 4. The loader 2, unloader 3, and monitor 5 are disposed outside the housing 1a.

[0014] The receiving table 8 is a member for placing the lead frame 9 on its upper surface. The transport rail 6 is disposed between the loader 2 and the unloader 3 via the upper surface of the receiving table 8. The transport rail 6 transports the lead frame 9 placed on the loader 2 to below the bonding head 4 in order to perform wire bonding on the lead frame 9, and transports the lead frame 9 to the unloader 3 when wire bonding is completed.

[0015] Fixing jig 7 is disposed above receiving base 8, and fixes lead frame 9 together with receiving base 8. Details of fixing jig 7 will be described later.

[0016] The bonding head 4 is placed above the fixing jig 7 and can move up and down and left and right to perform wire bonding on the lead frame 9. The monitor 5 is attached to the outer surface of the housing 1a and displays program information and the progress status regarding wire bonding. This allows the user to check the program information and the progress status regarding wire bonding from outside.

[0017] One or more power semiconductor elements (not shown) capable of carrying a current of several A or more and several hundred A or less may be mounted on lead frame 9. When wire bonding is performed on a large-capacity semiconductor device, a gold, silver, copper or aluminum wire having a diameter of 100 μm or more may be set on bonding head 4.

[0018] 2 is a top view showing a main part of the semiconductor manufacturing apparatus 1. Specifically, it is a view seen from the bonding head 4 side to the lead frame 9 side.

[0019] 2, fixing jig 7 is placed on the upper surface of lead frame 9 which is placed on the upper surface of receiving base 8, and fixes lead frame 9 together with receiving base 8. Fixing jig 7 includes a main body 7a having a rectangular shape when viewed from above, an opening 7b, and a lead frame holder 15.

[0020] An opening 7b having a rectangular shape in top view is formed in the center of the main body 7a. The opening 7b exposes a wire bonding area in the lead frame 9 where wire bonding is performed. This makes it possible to perform wire bonding with the fixing jig 7 attached.

[0021] Moreover, the receiving base 8 is formed in a rectangular shape in a top view, and the outline of the receiving base 8 in a top view is larger than the outline of the opening 7b in a top view. Furthermore, the outline of the main body 7a in a top view is larger than the outline of the receiving base 8 in a top view. This makes it possible for the main body 7a and the receiving base 8 to fix the periphery of the wire bonding region in the lead frame 9.

[0022] The lead frame 9 has low rigidity because it is cut out by pressing or the like to form a circuit (not shown). That is, ultrasonic vibrations output from the bonding head 4 during wire bonding are not easily transmitted properly to the lead frame 9. When a semiconductor device has a large capacity, the size of the power semiconductor element is also large, and if multiple power semiconductor elements are mounted, the number of wires bonded increases, which in turn increases the wire bonding area.

[0023] In this way, since the opening 7b becomes wider in a large capacity semiconductor device, especially when wire bonding is performed near the center of the opening 7b, the ultrasonic vibration output from the bonding head 4 during wire bonding is not properly transmitted to a position on the lead frame 9 corresponding to the center of the opening 7b, and the bonding strength of the wire bonding is not stable.

[0024] To solve this problem, in this embodiment, seven rod-shaped lead frame pressers 15 are provided that protrude from the opening end of the opening 7b toward the inner periphery. The seven lead frame pressers 15 are arranged so as to be able to press the periphery of the wire bonding location, which is the location where wire bonding is actually performed, in the wire bonding area. The seven lead frame pressers 15 press the wire bonding area of ​​the lead frame 9 with low rigidity in the opening 7b from the bonding head 4 side to the conveyor rail 6 side (i.e., the receiving table 8 side). This allows the ultrasonic vibration output from the bonding head 4 during bonding to be properly transmitted to the lead frame 9 even in the case of a lead frame 9 with low rigidity, making it possible to stabilize the bonding strength of the wire bonding.

[0025] 2 shows seven lead frame holders 15, the number of lead frame holders 15 may be one or more, and the bonding strength can be further stabilized by arranging the lead frame holders 15 around the wire bonding locations. Also, the lead frame holder 15 may have a shape other than a rod shape.

[0026] Furthermore, the lead frame holder 15 may be detachable, or may be provided integrally with the opening end of the opening 7b. If the lead frame holder 15 is detachable, the lead frame holder 15 may be attached to a desired position at the opening end of the opening 7b. Furthermore, various detachable structures, such as various fitting structures, can be used as a structure for detachably attaching the lead frame holder 15 to the opening end of the opening 7b.

[0027] Next, a structure for adjusting the positions of the receiving base 8 and the fixing jig 7 will be described. Fig. 3 is a side view showing the main parts of the semiconductor manufacturing equipment 1. Fig. 4 is a top view showing the main parts of the semiconductor manufacturing equipment 1 with the fixing jig 7 and the first XY table 13a omitted. Fig. 5 is a side view showing the main parts of the semiconductor manufacturing equipment 1 with the fixing jig 7 and the first XY table 13a omitted.

[0028] As shown in Figures 2 and 3, the semiconductor manufacturing equipment 1 further includes a first XY table 13a (corresponding to the first table), an image processing camera 14, a first XY ball screw 11a (corresponding to the first ball screw), a first XY motor 10a (corresponding to the first motor), a control unit 17, a second XY table 13b (corresponding to the second table), a second XY ball screw 11b (corresponding to the second ball screw), a second XY motor 10b (corresponding to the second motor), and a sensor 16.

[0029] Based on a control program related to wire bonding stored in a memory that the control unit 17 has, the control unit 17 controls each part of the semiconductor manufacturing apparatus 1. The control unit 17 is, for example, a processor.

[0030] The first XY table 13a is formed in a rectangular frame shape when viewed from above. The portion of the receiving base 8 excluding its lower end portion is disposed in an opening 13a1 of the first XY table 13a, and the upper surface of the first XY table 13a and the upper surface of the receiving base 8 are positioned at the same height. A fixing jig 7 is disposed on the rectangular frame-shaped upper surface of the first XY table 13a via a lead frame 9. Therefore, the outer periphery of the fixing jig 7 is held by the first XY table 13a.

[0031] A first XY ball screw 11a and a first XY motor 10a are attached to at least two adjacent sides of the first XY table 13a, and the first XY ball screw 11a rotates by the driving of the first XY motor 10a. The driving of the first XY motor 10a is controlled by the control unit 17.

[0032] By rotating the first XY ball screw 11a, the first XY table 13a can move on the XY plane. By moving the first XY table 13a, the fixture 7 arranged above the first XY table 13a can also be moved on the XY plane. Here, the XY plane is a horizontal (lateral) surface. In other words, the first XY table 13a is a table for moving the fixture 7 on the XY plane.

[0033] The image processing camera 14 is disposed above the fixing jig 7, and detects first position information indicating the position of the lead frame 9 through the opening 7b of the fixing jig 7. The control unit 17 controls the driving of the first XY motor 10a based on the first position information detected by the image processing camera 14, thereby aligning the fixing jig 7 on the XY plane.

[0034] As shown in Figs. 3 to 5, the second XY table 13b is formed in a rectangular shape when viewed from above, and is disposed below the first XY table 13a. A support 8 is disposed on the upper surface of the second XY table 13b. A set of a second XY ball screw 11b and a second XY motor 10b is attached to at least two adjacent sides of the second XY table 13b, and the second XY ball screw 11b rotates by driving the second XY motor 10b. The driving of the second XY motor 10b is controlled by the control unit 17.

[0035] By rotating the second XY ball screw 11b, the second XY table 13b can move on the XY plane. By moving the second XY table 13b, the support 8 arranged on the upper surface of the second XY table 13b can also be moved on the XY plane. In other words, the second XY table 13b is a table for moving the support 8 on the XY plane. Note that the support 8 and the second XY table 13b may be provided integrally.

[0036] The sensor 16 is disposed around the second XY table 13b and detects second position information indicating the position of the second XY table 13b. The control unit 17 controls the driving of the second XY motor 10b based on the second position information detected by the sensor 16, thereby aligning the receiving base 8 on the XY plane.

[0037] As described above, the receiving base 8 is placed in the opening 13a1 of the first XY table 13a, and a clearance is provided between the receiving base 8 and the first XY table 13a so that the receiving base 8 and the first XY table 13a do not come into contact with each other when the receiving base 8 moves on the XY plane.

[0038] Next, the shape of the upper surface of the receiving stand 8 will be described. Fig. 6 is a top view showing another example of the receiving stand 8. Fig. 7 is a cross-sectional view showing a state in which a lead frame 9 is placed on another example of the receiving stand 8. Fig. 8 is a top view showing yet another example of the receiving stand 8.

[0039] If the lead frame 9 is flat, the upper surface of the receiving base 8 can also be made flat so that the ultrasonic vibrations output from the bonding head 4 during bonding are properly transmitted to the lead frame 9, thereby obtaining stable wire bonding joint strength.

[0040] 6 and 7, when the lead frame 9 has a step, by providing a recess 8a capable of accommodating the step of the lead frame 9 in the area on the upper surface of the support 8 where the lead frame 9 is placed, the ultrasonic vibration can be properly transmitted to the lead frame 9, and the bonding strength of the wire bonding can be stabilized. Also, the support 8 may be moved on the XY plane to match the step of the lead frame 9.

[0041] Furthermore, as shown in FIG. 8, a plurality of receiving bases 8 may be connected to each other to arrange a plurality of lead frames 9.

[0042] Next, a description will be given of adjustment of the initial position of the fixing jig 7. Fig. 9 is a diagram showing a display on the monitor screen when adjusting the position of the fixing jig 7.

[0043] The adjustment of the initial position of the fixing jig 7 is performed in order to fix the lead frame 9 in the same position every time, in order to obtain stable bonding strength of the wire bonding.

[0044] The control unit 17 acquires and learns the first position information detected by the image processing camera 14 as a past history, and controls the driving of the first XY motor 10a so as to adjust the initial position of the fixing jig 7 based on the learning result of the past history. That is, the control unit 17 performs fine adjustment in advance for the initial position of the fixing jig 7 based on the past history. This reduces the frequency and amount of position adjustment of the fixing jig 7, thereby improving the manufacturing efficiency of the semiconductor device.

[0045] Learning of past history can be achieved, for example, using AI (Artificial Intelligence) technologies such as machine learning and deep learning, which enables more advanced learning.

[0046] 9, the horizontal axis indicates the X-axis and the vertical axis indicates the Y-axis. The intersection of the X-axis and the Y-axis is displayed in the upper left as the XY coordinates. Furthermore, the frame 20a on the left side indicates the correct position where the fixing jig 7 should be placed, and the frame 20b on the right side indicates the current position of the fixing jig 7. The current position of the fixing jig 7 is the position of the fixing jig 7 after it is placed on the lead frame 9 and before the fixing jig 7 holds the lead frame 9.

[0047] The control unit 17 controls the driving of the first XY motor 10a so as to align the right frame 20b with the left frame 20a. In the next wire bonding, the control unit 17 controls the driving of the first XY motor 10a so as to shift the fixing jig 7 by the amount of the current position adjustment.

[0048] <Method of Manufacturing Semiconductor Device> Next, a description will be given of a method for manufacturing a semiconductor device using the semiconductor manufacturing apparatus 1. FIG 10 is a flowchart showing a method for manufacturing a semiconductor device using the semiconductor manufacturing apparatus 1.

[0049] As shown in FIG. 10, first, the control unit 17 transports the lead frame 9 from the loader 2 on the transport rail 6, and places the lead frame 9 on the upper surface of the receiving table 8 (step S1), and then the control unit 17 places the fixing jig 7 on the upper surface of the lead frame 9.

[0050] Next, the control unit 17 checks the positional relationship between the lead frame 9 and the receiving table 8 using the sensor 16, and adjusts the position of the receiving table 8 together with the second XY table 13b by moving the second XY table 13b based on the second position information detected by the sensor 16 (step S2).

[0051] Next, the control unit 17 adjusts the position of the fixing jig 7 together with the first XY table 13a based on the first position information detected by the image processing camera 14 (step S3). At this time, the position of the lead frame holder 15 provided on the main body 7a of the fixing jig 7 is also adjusted.

[0052] Next, the control unit 17 presses the fixing jig 7 against the lead frame 9 to fix the lead frame 9 between the fixing jig 7 and the receiving stand 8 (step S4), and then checks the position and size information of the wire bonding area on the lead frame 9 with the image processing camera 14 and performs wire bonding (step S5).

[0053] Next, the control unit 17 moves the fixing jig 7 upward to release it from the lead frame 9 (step S6), and then transports the lead frame 9 to the unloader 3 side on the transport rail 6, and stores the lead frame 9 in the unloader 3 (step S7).

[0054] Finally, the lead frame 9 is covered with a sealing resin (step S8) to complete the semiconductor device.

[0055] <Effects> As described above, the semiconductor manufacturing apparatus 1 of the embodiment comprises a receiving table 8 for placing a lead frame 9 on its upper surface, and a fixing jig 7 that is positioned above the receiving table 8 and fixes the lead frame 9 between the receiving table 8, and the fixing jig 7 has a main body 7a that holds the upper surface of the lead frame 9, an opening 7b that exposes a wire bonding area in the lead frame 9 where wire bonding is performed, and a lead frame presser 15 that presses the wire bonding area of ​​the lead frame 9 towards the receiving table 8 at the opening 7b.

[0056] Therefore, even in the case of a large-capacity semiconductor device, the wire bonding area of ​​the lead frame 9 can be firmly fixed by the lead frame holder 15 of the fixing jig 7. This allows the ultrasonic vibration during wire bonding to be properly transmitted to the lead frame 9, and a stable bonding strength of the wire bonding can be obtained. As a result, the yield of the semiconductor device can be improved.

[0057] The semiconductor manufacturing equipment 1 also includes a first XY table 13a that holds the outer periphery of the fixing jig 7, an image processing camera 14 that detects first position information indicating the position of the lead frame 9 through an opening 7b of the fixing jig 7, a first XY ball screw 11a attached to the first XY table 13a, a first XY motor 10a that moves the fixing jig 7 laterally together with the first XY table 13a by rotating the first XY ball screw 11a, and a control unit 17 that controls the drive of the first XY motor 10a based on the first position information detected by the image processing camera 14.

[0058] Therefore, it is possible to improve the accuracy of alignment between the lead frame 9 and the fixing jig 7. This makes it possible to obtain a more stable bonding strength of the wire bonding.

[0059] The semiconductor manufacturing equipment 1 also includes a second XY table 13b having a receiving base 8 disposed on its upper surface, a second XY ball screw 11b attached to the second XY table 13b, a second XY motor 10b that moves the receiving base 8 laterally together with the second XY table 13b by rotating the second XY ball screw 11b, and a sensor 16 that detects second position information indicating the position of the second XY table 13b, and a control unit 17 controls the driving of the second XY motor 10b based on the second position information detected by the sensor 16.

[0060] Therefore, it is possible to improve the accuracy of alignment between the receiving base 8 and the lead frame 9. This is particularly effective when the lead frame 9 has a step and a recess 8a is formed in the receiving base 8, and more stable bonding strength of the wire bonding can be obtained.

[0061] In addition, the control unit 17 acquires and learns the first position information detected by the image processing camera 14 as past history, and controls the driving of the first XY motor 10a to adjust the initial position of the fixing jig 7 based on the learning results of the past history.

[0062] Therefore, the frequency and amount of position adjustment of the fixing jig 7 is reduced, and the manufacturing efficiency of the semiconductor device is improved.

[0063] The embodiment can be modified as appropriate. [Explanation of symbols]

[0064] 1 semiconductor manufacturing apparatus, 7 fixing jig, 7a main body, 7b opening, 8 receiving stand, 9 lead frame, 10a first XY drive motor, 10b second XY drive motor, 11a first ball screw, 11b second ball screw, 13a first XY table, 13b second XY table, 14 image processing camera, 15 lead frame holder, 16 sensor, 17 control unit.

Claims

1. a support for placing a lead frame on an upper surface thereof; a fixing jig disposed above the support base and fixing the lead frame to the support base; A first table that holds an outer periphery of the fixing jig; an image processing camera that detects first position information indicating a position of the lead frame through an opening of the fixing jig; a first ball screw attached to the first table; a first motor that rotates the first ball screw to move the fixture together with the first table in a lateral direction; a control unit that controls driving of the first motor based on the first position information detected by the image processing camera, The fixing jig is a semiconductor manufacturing device having a main body that holds the upper surface of the lead frame, an opening that exposes a wire bonding area where wire bonding is performed on the lead frame, and a lead frame presser that presses the wire bonding area of ​​the lead frame toward the receiving table at the opening.

2. a second table on whose upper surface the pedestal is disposed; a second ball screw attached to the second table; a second motor that rotates the second ball screw to move the support together with the second table in the lateral direction; a sensor for detecting second position information indicating a position of the second table; The semiconductor manufacturing apparatus according to claim 1 , wherein the control unit controls driving of the second motor based on the second position information detected by the sensor.

3. 3. The semiconductor manufacturing apparatus of claim 2, wherein the control unit acquires and learns the first position information detected by the image processing camera as past history, and controls the driving of the first motor to adjust an initial position of the fixing jig based on a learning result of the past history.

4. A method for manufacturing a semiconductor device using the semiconductor manufacturing apparatus according to claim 2 or 3, comprising the steps of: (a) placing the lead frame on an upper surface of the pedestal; (b) placing the fixture on an upper surface of the lead frame; (c) adjusting the position of the cradle together with the second table based on the second position information detected by the sensor; (d) adjusting the position of the fixture together with the first table based on the first position information detected by the image processing camera; (e) fixing the lead frame with the fixing jig and the support; (f) performing wire bonding on the wire bonding area of ​​the lead frame; The manufacturing method of a semiconductor device comprising the steps of:

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