| abstract |
PURPOSE: To inhibit the plasticity and fluidity of an Al layer at a pad part in an ultrasonic bonding of a fine metal wire and to prevent the generation of an Al layer by a method wherein a thin film, which has a hardness higher than that of the Al layer and has a good bonding property to the Al layer, is provided on the surface of the Al layer. n CONSTITUTION: A silicon oxide film 2 is provided on a silicon substrate 1, an Al layer 3 is deposited on the film 2 in a thickness of 1 to 3μm, a thin film; which has a hardness higher than that of the layer 3, has a good bonding property to the layer 3, contains Co, Cr, Ni, W, Cu or Si of 1 to 2%, for example, and consists of Al, WSi or the like; is deposited on the layer 3, this thin film is selectively etched in order and a pad part of a two-layer structure consisting of the layer 3 and the thin film 4 is formed. Then, a protective film 5 is deposited on the surface including the pad part and the film 5 on film 4 is selectively etched to provide an opening part 6. At the time of bonding, a fine metal wire is pressed on the surface of the film 4 and is subjected to ultrasonic vibration. Thereby, the fine metal wire breaks the film 4 and is bonded to the layer 3. Here, the film 4 inhibits the plastic flow of the Al layer due to the ultrasonic vibration to prevent the generation of an Al layer and a good bonding can be realized. n COPYRIGHT: (C)1991,JPO&Japio |