JPH06342829A - Bonding tool - Google Patents

Abstract

PURPOSE:To easily materialize the balance of the head tip of a bonding tool and equally pressurize the outer lead of a semiconductor device at bonding by constituting the head of the bonding tool out of two parallel boards. CONSTITUTION:A plate 105, where a head tip 103 is attached, is set in the groove B provided in a substrate 101, in such form as to catch a spring 106 in the middle. The board 105 is bent after inserted in the groove of the substrate 101 together with a spring 106 so that it may not fall off the substrate 101. In the bonding tool being constituted this way, the board 105, where a head tip 103 is attached, slides inside the groove B, so when load is applied to the bonding tool, the board slides so that it may absorb warp of the board 110 or the dispersion of thickness of the board 110 and outer leads 113, therefore the outer leads 113 of a semiconductor device 112 can be pressurized nearly equally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a bonding tool used for connecting external connection leads of a semiconductor device to a printed board or the like.

[0002]

2. Description of the Related Art Conventionally, a bonding tool used for connecting an external connection lead of a semiconductor device to a wiring pattern such as a printed circuit board has a structure shown in FIG.

FIG. 4 is a cross-sectional view showing the structure of a conventionally used bonding tool, 201 is a base of the bonding tool, 202 is a shaft for attaching the bonding tool to a bonding apparatus, and 203a and 203b are oxidation by heat during bonding. A tip chip 204 made of a substance such as diamond or titanium nitride, which is hard to cause the attachment of foreign matter, is a heater.

In the conventional bonding tool, as shown in the figure, a metal block is cut into a U-shape like a base body 201, a shaft 202 is welded to the base body 201, and a tip tip 203 is formed.
The a and 203b are brazed to the U-shaped ends of the base 201 by a method such as gold brazing. At the time of bonding, the heater 204 attached to the substrate 201 is heated to an appropriate temperature determined by the pressure bonding method to perform bonding.

[0005]

However, in the conventional bonding tool, it is difficult to mount the tip chips 203a and 203b in equilibrium with each other when the tip chips 203a and 203b are mounted, and a deviation of the equilibrium of 10 μm or more usually occurs. If the external leads of the semiconductor device are connected to a printed circuit board using a bonding tool that is out of balance in this way, the load applied to the leads on one side of the external leads will be too large and the leads will be crushed too easily to break the leads. Then, the load applied to the lead is weak and sufficient connection strength cannot be obtained.

Further, when the bonding tool is attached to the bonding apparatus by using the shaft 202, the substrate to be connected and the tip chips 203a and 203b must be attached in parallel, and the parallelism must be always maintained and managed. It was a major cause of time variability. Further, it is impossible to absorb the unevenness of the pressure due to the warp of the substrate on which the semiconductor device is mounted and the variation in the thickness of the external leads of the semiconductor device, which causes a decrease in the yield during mass production.

The present invention has been made to solve the above problems, and it is possible to easily realize the balance of the tip of the bonding tool and uniformly press the external leads of the semiconductor device at the time of bonding. The purpose is to provide.

[0008]

A bonding tool according to the present invention is a bonding tool for pressure-bonding and externally connecting an external connection lead of a semiconductor device and a wiring on a substrate on which the semiconductor device is mounted, by using the bonding tool. It is characterized in that the tip is composed of two parallel plates.

Alternatively, the bonding tool of the present invention is characterized in that the plate is attached to the base of the bonding tool by a spring.

Alternatively, in the bonding tool of the present invention, one end of the plate is accommodated in each sliding portion provided on the plate inside the base of the bonding tool, and each sliding portion is inside the bonding tool. The pipe is electrically connected, and the sliding portion and the inside of the pipe are filled with mechanical oil.

[0011]

【Example】

(Embodiment 1) FIG. 1 is a sectional view showing an embodiment in which a semiconductor device is pressure-bonded to a substrate using a bonding tool according to the present invention, and FIG. 2 shows a main part of FIG. It is sectional drawing cut | disconnected in the direction. In the figure, 101 is a base body made of carbon steel or the like, 102 is a shaft welded to the base body 101 for attaching a bonding tool to a bonding apparatus, and 103 and 103a and 103b are materials that are not easily oxidized, such as artificial diamond and titanium nitride. The tip chip made by 1., 104 is a heater for heating the entire bonding tool, 105 is a plate for adhering the tip chip, 106 is a spring, 110 is a printed circuit board, 111 is a wiring pattern on the printed circuit board, and 112 is a TAB semiconductor device. , 113 are external leads of the TAB semiconductor device 112, and B is the substrate 10.
1 is a groove portion provided in the first.

From the sectional views shown in FIGS. 1 and 2, the plate 105 to which the tip 103 is attached is fitted into the groove B provided in the base 101 with the spring 106 interposed therebetween. As shown in FIG. 2, the plate 105 has the spring 106 and the plate 105 inserted into the groove of the base 101 so as not to fall off from the base 101, and the portion a is bent. In the bonding tool configured as described above, the plate 105 having the tip chip 103 attached thereto slides in the groove B, so that when a load is applied to the bonding tool, the plate 105 warps the substrate 110 and the substrate 110 and the external leads 113. The external leads 113 of the semiconductor device 112 can be pressed almost evenly because they slide so as to absorb the thickness variation.

(Embodiment 2) FIG. 3 is a sectional view showing an embodiment according to the present invention, in which 107 is a tube formed by hollowing the inside of the substrate 101, 108 is a sealing rubber, and 10 is a sealing rubber.
9 is a machine oil, and the other symbols are the same as those used in Example 1.

As shown in the drawing, the plate 105 having the tip 103 attached thereto is fitted into the groove B, and the two groove B are connected by the pipe 107, and the groove B and the inside of the pipe 107 are filled with the mechanical oil 1.
It is filled with 09. The sealing rubber 108 is fitted on the plate 105 to prevent the mechanical oil 109 from flowing out.

In the bonding tool configured as described above, since the left and right tip chips always slide so as to follow the substrate, bonding is performed while always automatically correcting the left-right variation for each substrate. Non-uniformity can be eliminated and good connection can be obtained.

[0016]

As described above, according to the bonding tool of the present invention, when mounting a semiconductor device on a substrate,
External leads of semiconductor devices can always be automatically connected with a uniform load, and high connection reliability can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing mounting using a bonding tool according to the present invention.

FIG. 2 is a cross-sectional view showing mounting using the bonding tool according to the present invention.

FIG. 3 is a cross-sectional view showing a bonding tool according to the present invention.

FIG. 4 is a sectional view showing a conventionally used bonding tool.

[Explanation of symbols]

 101 Base 102 Shaft 103 Tip Chip 104 Heater 105 Plate 106 Spring 107 Tube 108 Sealing Rubber 109 Machine Oil 110 Printed Circuit Board 111 Wiring Pattern 112 Semiconductor Device 113 External Lead 201 Base 202 Shafts 203a, 203b Tip Chip 204 Heater

Claims (3)

[Claims] 1. A bonding tool for crimping an external connection lead of a semiconductor device and a wiring on a substrate on which the semiconductor device is mounted by pressure and heat, wherein the tip of the bonding tool is composed of two parallel plates. Bonding tool characterized by being used. 2. A bonding tool, wherein the two parallel plates according to claim 1 are attached to a base of the bonding tool by a spring. 3. One end of the plate is housed in each sliding part provided on the plate in the base of the bonding tool, and each sliding part is conducted by a tube in the bonding tool, The bonding tool according to claim 1, wherein the sliding portion and the inside of the pipe are filled with mechanical oil.