JPH0216745A - Wire clamp plate - Google Patents

Abstract

PURPOSE:To improve a wear resistance and prevent stripping of coating without generating static electricity by forming a wire clamp plate by the use of a silicon carbide sintered compact and coating its plate with TiN or TiC. CONSTITUTION:Clamp plates 1 and 2 where a wire is sandwiched directly between their pointed ends are shaped into the form of a silicon carbide sintered compact. Its compact is coated with TiN or TiC. TiN and TiC have high hardness and exhibit a wear resistance; besides, they are also superior in conductivity. As a result, they prevent the generation of static electricity. Being formed in such a sintered compact, the wire clamp plate improves a wear resistance and prevents stripping of coating without generating static electricity.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a wire clamp plate, and particularly to a clamp plate that directly clamps a wire in a wire bonding device used to connect semiconductor chips with wires such as gold wire. It is.

(Prior Art) A wire bonding device that connects semiconductor chips with wires such as gold wire is provided with a clamp plate that directly clamps the wire at its tip.
As shown in the figure, it has a fixed plate 1 and a movable plate 2, and the movable plate 2
is in operation moving to the fixed plate side. This wire clamp plate 1.2 connects semiconductor chips one after another while repeatedly clamping and unclamping the wire W, and is required to have excellent continuity in wire bonding.

In other words, if the wire gets stuck to the tip of the tool during wire bonding, the wire bonding will be interrupted and the wire bonding will be interrupted.
Bonding continuity deteriorates.

Therefore, various improvement measures have been considered, and for example, as in Japanese Patent Laid-Open No. 63-78544, it has been proposed to cause the tool to vibrate ultrasonically to prevent the wire from sticking.

(Problems to be Solved by the Invention) On the other hand, in order to improve the continuity of wire bonding, wire clamp devices are being studied from the viewpoint of materials.

In other words, conventional wire clamp plates made of cermet such as carbide have been used, but this has the disadvantage that the wire comes into contact with the clamp plate as it travels, causing the clamp plate to wear out and become unusable for long periods of time. Therefore, rubies coated with TiN have recently come into use.

The reason why ruby is coated with TiN is that when ruby is used alone, static electricity is generated by contact with running wires, and the static electricity causes the wires to curl or become tangled, making them unusable.

However, even if ruby is coated with TiN, its adhesion is not very good and it will eventually peel off, making it impossible to use it for a long time.

Therefore, the ruby clamp plate from which the TiN has peeled off is recoated with TiN and used, but the service life is short and replacement work is frequent, and it also costs a lot of money to redo the TiN coating, making it less economical. There was a problem with this.

The present invention has been made in order to solve the problems of the prior art described above, and provides a clamper that clamps wires when connecting semiconductor chips. The object of the present invention is to provide a wire clamp plate that can significantly improve properties.

(Means for Solving the Problems) In order to achieve the above object, the present inventor has developed a material that has high hardness, wear resistance, and static electricity as a coating material for a clamp plate that directly clamps a wire at its tip. In order to prevent this from occurring, we decided to coat it with TiN or TiC, which has good electrical conductivity, and in this case, we conducted extensive experimental research on materials that would not easily peel off after coating.

As a result, although TiN and TiC have the advantages mentioned above, the material to be coated, that is, the wire clamp plate, does not have good adhesion and peels when used with conventional cermet or ruby. Only in case
It has been discovered that it exhibits excellent adhesion to TiN and TiC, and the present invention has been made here.

In short, the clamper according to the present invention has a structure in which the clamp plate that directly clamps the wire at the tip is a sintered silicon carbide body, and the sintered silicon carbide body is coated with TiN or TiC. .

The present invention will be explained in more detail below.

Wire clamp plates made of silicon carbide (SiC) sintered bodies are manufactured by: - For boat fishing, granules of fine silicon carbide powder are formed into a predetermined shape using a die press, degreased and sintered, and then ground and polished. The surface to be coated with TiN or TiC is processed to have a mirror finish.

Silicon carbide sintered body has superior thermal conductivity compared to ruby, alumina, etc., so it can easily dissipate the frictional heat generated when the wire comes into contact with the clamp plate while running, reducing wear. . However, a silicon carbide sintered body alone cannot be used because it generates static electricity, and it also lacks wear resistance, so there is a limit to how long it can be used.

Therefore, in the present invention, a silicon carbide sintered body is coated with either TiN or TiC.

That is, as mentioned above, TiN and TiC have high hardness and wear resistance, and have good conductivity, so they can prevent the generation of static electricity. There is a problem. Therefore, as a result of various studies on materials that have good adhesion to TiN and TiC, the present inventor found that silicon carbide sintered bodies are
It was found that it had very good adhesion. However, although AQ203 sintered bodies were also considered, the adhesion was not good, and even if TiN or TiC was coated on them, they would peel off.

Note that there are no particular restrictions on the coating method for TiN and TiC6. For example, various PVD coating methods can be used, and ion blating method is easy. A suitable thickness of the coating is 1.0 to 5.0 μm.

(Example) Next, examples of the present invention will be shown.

A disk with a diameter of 4III11, a thickness of 1 mm, and a surface roughness of 0.03 μm is made of χ lid plexus silicon carbide sintered body, and T
A 2 μm thick iN coating was applied by arc discharge type high vacuum ion blating method.

As a result of attaching this clamp plate to a clamper and using it at a bonding speed of 0.2 seconds, the coating surface was worn out after 3 weeks of use, and it was time to replace it.

Further, the above disk was coated with TiC to a thickness of 2 μm using the same method.

This clamp plate was attached to a clamper and used at a bonding speed of 0.2 seconds. After 5 weeks of use, the coated surface was worn out and it was time to replace it.

One ruby with a diameter of 4 mm, a thickness of 11 mm, and a surface roughness of 0.
A 0.3μm disk was manufactured, and TiN was deposited on this disk to a thickness of 2μm using an arc discharge type high vacuum ion blating method.
Coating was carried out.

When this clamp plate was attached to a clamper and used at a bonding speed of 0.2 seconds, the coating began to peel off after one week.

(Effects of the Invention) As explained above, according to the present invention, the wire clamp plate is made of silicon carbide sintered body and is coated with TiN or TiC, so that it has excellent wear resistance and good adhesion. , without the coating peeling off.
However, since static electricity is not generated even when the wires come into contact, it can be used for a long time, the continuity of wire bonding can be significantly improved, and the cost required for manufacturing the clamp plate can be reduced.

[Brief explanation of the drawing]

FIG. 1 is an explanatory sectional view showing a clamp plate in a wire bonding device. 1...Fixed plate, 2...Movable plate. Patent Applicant: Showa Denko K.K. Patent Attorney Takashi Nakamura Supplementary Procedure Device 1, Indication of Case Patent Application No. 166499 of 1988 2, Name of Invention Wire Clamp Plate 3, Person Making Amendment Relationship with Case Patent Application Address: 2-10-12 Shiba Daimon, Minato-ku, Tokyo Name (2
00) Showa Denko Co., Ltd. 4, Agent address: 5-35-5-6, Nishi-Nippori, Arakawa-ku, Tokyo 116, Contents of amendment (1) Description of "3 weeks use" on page 7, line 4 of the specification "Used for 10 months" on the 10th line of the same line was corrected to "Used for 12 months" and the statement of "In 1 week" on the 19th line of the same line was changed to "Used for 6 months." Correct to ``de''.

Claims (1)

[Claims] In a clamper that clamps a wire when connecting a semiconductor chip, the clamp plate that directly clamps the wire at its tip is made of a silicon carbide sintered body, and the silicon carbide sintered body is one of TiN and TiC. A wire clamp plate characterized by being coated.