| abstract |
The purpose of the present invention is to provide the discharge electrode for wire bonding apparatus capable of ensuring stable discharging. The discharge electrode 20 is formed to have a straight bar shape; and the electrode core 24 surface is covered with aluminum oxide film 26 which has been undergone with sealing hole process. At the front end, an exposed face 28 of the exposed electrode core 24 is disposed at a position deviated from the straight bar central axis. The exposed face 28 faces the front end of the lead on the discharge side to limit the discharge direction. The formation steps of aluminum oxide film 26, in which aluminum oxide film has been undergone with sealing-hole process, are divided into two stages. In the first step, aluminum oxide film with porous structure is formed on the electrode core 24 surface; for example, plasma coating method or anodic oxidation method is used to form aluminum oxide film for about 6 μm on the surface of electrode core. In the second step, a sealing-hole process is conducted onto the porous structure; for instance, laser PVD method is used to adsorb the aluminum oxide film, or resin is used to perform sealing-hole process. |