| 摘要 |
PURPOSE:To contrive to reduce cost of a semiconductor device, and to generate no deterioration of bonding strength by a method wherein the inside electrode of the device is made to have the three layer construction of Al - a diffusion preventing metal - Al, and a silver ball is thermocompression bonded to the part thereof. CONSTITUTION:The inside electrode of a semiconductor device is made to have the three layer construction of Al 2-a diffusion checking metal 6-Al 2, and a silver ball 1 is thermocompression bonded to the part thereof. Accordingly, a condition to make silver 6 and Si dioxide 3 to come in contact directly can be checked. As the metal 6, any metal to make no solid solution with silver at least at the temperature of 400 deg.C or less, and moreover having favorable adhesion with Al is favorable. By constructing the semiconductor device in such a way, the Al 2 of the uppermost layer diffuses in the silver ball 1, while diffusion of silver into the Al of the lowest stage and into the copper of the middle layer are hardly generated. Therefore, the value of bonding strength is not changed from the value directly after bonding, and bonding of high reliability can be realized. |
