MANUFACTURE OF SEMICONDUCTOR DEVICE

• Main Authors: KATSURA TADASHI, SHIMANUKI MAKOTO
• Format: Patent
• Language: English
• Published: 13.08.1984
• Edition: 3
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PURPOSE:To eliminate the forming process of silver plated layer on pad layer saving precious metal and simplifying manufacturing process by a method wherein after cleaning up the surface of bonding pad layer, a complex salt layer formed on the surface whereon a backside gold evaporated layer of semiconductor element is placed and further heated and pressurized for fusion welding as necessary. CONSTITUTION:A metallic frame 1 mainly comprising copper preliminarily stamped and formed is cleaned up and any oxide or sulfide on the surface is removed. Next a complex salt layer 13 is formed on the cleaned up copper surface by means of immersing the frame 1 in ''Ever bright-Cu'' as a brand name and drying up the same. This complex salt so far formed is relatively stable in room temperature with heat resistance up to 125 deg.C to be decomposed and sublimated by heating up to the temperature exceeding 150 deg.C with the surface assuming the color of an oxide. On the other hand, a backside gold evaporated layer 11 of a semiconductor element 10 may be made around 3mum thick to save the conventional solder itself and the layer 11 is placed directly on the surface complex salt layer 13 of a bonding pad layer 2 to be heated and further pressurized to fusion welding as necessary.