JPS5918861B2 - die bonding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic assembly apparatus for semiconductor integrated circuit devices, and particularly to a die bonding apparatus.

Glass-sealed ceramic cases are required to have high quality due to the nature of their packaging, and are also sought after for low cost. Coupled with this variation, automation is slower than molded resin packaging. Conventionally, the die bonding process
The crimping process is also performed separately, which is one of the reasons for the high cost of the ceramic case since the man-hours for the two steps account for a large proportion of the total assembly man-hours. In addition, ceramic cases have a high heat capacity, and both the die bonding process and the compression bonding process require high temperatures and large amounts of heat. Separate processing of the two processes requires heating the product twice, which reduces thermal loss. Not only is this a problem, but it is thought to have a negative impact on the product as well. Conventionally, the crimping process has been carried out manually, and as shown in FIGS. 2 and 3, the glass 30 is heated on a heater block 29 to become molten.
The lead frame 4 was crimped using tweezers or the like to the base 5, which was coated with a metal oxide, resulting in damage to the lead frame, uneven positioning of the lead frame, poor efficiency, and a heavy burden on the worker. There was a problem.

SUMMARY OF THE INVENTION An object of the present invention is to improve the above-mentioned drawbacks and provide a die bonding device with high working efficiency that is equipped with an automatic lead frame crimping device.

When trying to mechanize the die bonding process and the crimping process and process the two processes consecutively with one device, the problem is whether to process the crimping process first or the die bonding process first. become.

Regarding the ceramic case that is the target of this device, due to the heat capacity of the case, the conveyance section that guides the case to the die bonding process position and the crimping process position and connects and connects the two process processes is a ceramic case. Because it must be heated to a level that enables die bonding and compression bonding processes, it must be kept at a high temperature. Furthermore, a vibration mechanism (not shown) is provided in the transport portion at the die bonding process position in order to better die bond the IC chip to the base. Therefore, if the crimping process is performed before the die bonding process, the lead frame will already be crimped at the time of die bonding, and in this state, the glass on the base will be molten, so the lead frame will not be completely fixed. Since the vibration mechanism and the transport mechanism attached to the transport part are not only extremely complicated due to consideration for the lead frame, but also because the glass melted by pressure bonding is It may flow into the cavity 32 (see FIG. 3) where die bonding is to be performed, resulting in a defective product. However, this apparatus employs a method in which the pressure bonding process is performed after the die bonding process. Next, embodiments of the present invention will be explained using figures.

As shown in FIG. 1, the shape of the conveyor/heater block 1 is such that a concave groove is provided so that the base 5 can fit smoothly into it, and the back side of the base 5 that has entered the groove is attached to the heater block 1.
It is designed to come into contact with the high temperature part of the The grooves of the heater block 1 are arranged in a straight line and continuously, and are maintained at a high temperature (the pace placed on the surface of the heater block 1 can move smoothly on the grooves of the base). Conveyance and driving are performed by movement of the feed bar 12, which is equipped with feed pawls 31 arranged at equal pitches, in the direction of the arrow a in FIG. Force is transmitted from a transport drive shaft 12 to which a cylindrical cam 6 is fixed, and the base 5 is fed by one pitch with each rotation of the shaft 12.The base 5 supplied to the transport/heater block 1 is fed and heated one pitch at a time in each cycle of this device, and reaches the die bonding process position (directly below the die collet axis 10).The die bonding arm 3 is attached to the tie bonding arm with respect to the base 5 in the die bonding process position. By driving the shaft 11, the IC chip vacuum-adsorbed to the die collet mounted on the die collet shaft 10 is transferred to the VC. The die bonding arm 3 is lowered, a load is applied to the IC chip on the cavity 32, and a vibrating rock structure (not shown) is activated to complete the die bonding and the die bonding arm 8 is moved.
returns to the stop position when the device was started. At the end of the die bonding, the glass 30 coated on the base 5 is sufficiently heated to a molten state, and the lead frame is sufficiently crimped. After the die bonding is completed, the conveyance mechanism is activated, and the die-bonded base 18 is sent over the conveyance heater block 1 while holding the molten glass until it reaches the position 18 in FIG. 1, where the automatic crimping device is activated. Then, the lead gnome 4 is crimped. The automatic crimping device moves the base 5 to a crimping process position (the position of the base 18 in FIG. 1) using a feed claw 31 connected to the conveyor bar 2.
Transport it to Hess to confirm that the preparations for the crimping process are complete.
A timing cam 7 fixed to the drive shaft 13 of the conveyance 5 operates a micro SW 8 which is turned on and off by the timing cam 7, detects a signal, starts, and completes the operation during the operating time of the vibration mechanism in the die bonding process.

Therefore, in this device, the operating time of the automatic crimping device has no effect on the cycle time of the device. The automatic crimping device presses the pressure body 2 of the supplied lead frame 4.
0 positioning function, a function of adsorbing the lead frame 4 using a magnet on the pressurizing body 20, and positioning the adsorbed lead frame 4 on the conveying heater block 1, directly below the pressure body 20. It has three functions: the function of thermo-compression bonding the molten glass sent to the base 18 holding it with zero force.

The operation will be explained step by step. The slide bar 17 is rotated about the slide bar arm shaft 15 of the slide bar arm 14 acting on the slide bar pin 33 which is driven into the slide bar 17 and fixed therein, and the slide bar 17 is rotated in contact with the slide bar guide 16 as shown in FIG. It moves only in the middle B and b' directions, and moves the supplied lead frame 4 in the direction of the pressurizing body 20. Movement of the slide bar arm 14,
The movement of the pressurizing body 20 and the movement of the magnet upper and lower arms 24 are timed by three cams (not shown) lined up on one shaft, and the slide bar 17 is
While moving in the direction shown in FIG. The mechanism is such that the support rod 23 and the magnet 28 driven into the magnet support rod 23 rise. On the other hand, the positional relationship between the magnet support rod 23 and the pressurizing body 20 is in the state shown in FIG. The magnet 28 does not attract the lead frame 4 in a state where the relative position with the pressurizing body 20 has not yet been determined. FIG. 4b shows a state in which the lead frame 4 that has been fed is in contact with the lead frame guide 21 and the relative position between the pressurizing body 20 and the lead frame 4 is exposed. In this state, the magnet upper and lower arms 24 are lowered, and at the same time, the magnet support rod 23 is lowered to a position where the magnet support rod positioning pin 26 driven into the magnet support rod 23 contacts the pressurizing body 20, and the above-mentioned relative position is reached. The magnet 28 attracts the lead frame 4 to the state shown in FIG. 4a, and the slide bar 17 moves to the state shown in FIG. 1b.
After the slide bar 17 is completely removed from the pressurizing body 20, the pressurizing body 20 descends while adsorbing the lead frame 4 in the state shown in FIG. 4a, and moves in the direction shown in FIG. 1C. The base 18 holds the molten glass at the crimping process position.
The lead frame 4 is pressurized and crimped to the proper position. The pressurizing body 20 has heater holes 2 provided in the pressurizing body 20.
The lead frame 4 is heated to an appropriate temperature by the heater fitted in the lead frame 2, and heat is rapidly removed from the molten glass on the base during crimping, thereby preventing the glass from solidifying. There is. After applying pressure V+2U and crimping, the magnet upper and lower arms 23 rise, the magnet 28 separates from the surface of the lead frame 4, and after the adsorption of the lead frame 4 is released, the heating body 20
rises to complete the crimping operation. Even after the lead frame 4 is crimped, the base 19 remains placed on the conveyance/heater 1 and continues to be conveyed and heated for a predetermined period of time. During this heating state, complete adhesion occurs between the lead frame 4 whose surface has been oxidized and the molten glass, and when the heating is removed and the lead frame is cooled, the desired crimped state of the lead frame is obtained. After completing the die bonding process and the crimping process, the conveying mechanism is driven and the base 5,
18 and 19 are fed one pitch to complete one cycle of this device.

According to the present invention, since the lead frame 4 is not yet crimped during die bonding, there is no restriction due to the lead frame 4 during die bonding.
Since the vibration mechanism can be attached, the yield of die bonding is improved, and the applicable C chip size can be selected more easily than before.

Furthermore, during die bonding, there is no possibility that molten glass will flow into the cavity 32 and make the product defective.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the present invention, Fig. 2 is a perspective view showing a conventional manual crimping process, and Fig. 3 is a perspective view showing a glass-sealed ceramic case substrate used in this device. , FIGS. 4a and 4b are cross-sectional views of the cut plane in FIG. 1 taken from the d direction. 1. Transfer and heater block, 2. Transfer lever, 3. Die bonding arm, 4. Lead. Frame, 5.
...Base, 6...Cylindrical cam, 7...
...Timing cam, 8...Micro switch, 9...Cam follower 10...
Die collet shaft, 11...Die bonding arm axis, 12...Transport drive shaft, 13...
・Drive bearing, 14...Slide bar arm,
15...Slide bar arm shaft, 16...
...Slide bar guide, 17...Slide bar,
18...Base after die bonding, 19...
... Base after crimping, 20 ... Pressure body, 21
... Read frame guide, 22 ... Heater hole, 23 ... Magnet support bar, 24 ...
・Magnet arm, 25...Cam follower one, 26
...Magnet support rod positioning pin, 27...
・Compression spring, 28... Magnet, 29...
Heater block, 30... Sealing glass, 3
1... Feed claw, 32... Cavity 1.

Claims (1)

[Claims] 1. In a die bonding apparatus for die bonding a semiconductor integrated circuit chip to a substrate of a case for sealing a semiconductor integrated circuit device, there is provided a means for transporting the substrate over a heater block, and a means for transporting the substrate onto the substrate heated by the heater block. die-bonding means for die-bonding an integrated circuit chip; and a lead frame attached to the molten glass on the substrate at a position where the chip is die-bonded and transported over the heater block from the die-bonded position. and means for automatically bonding on a heater block.