SEMICONDUCTOR SWITCHING DEVICE AND METHOD OF MAKING SAME

• Main Author: WEBB, MONTY F
• Format: Patent
• Language: English
• Published: 21.07.1982
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

A triac device includes a first silicon chip having regions of alternate conductivity type disposed in a PM-junction forming relationship which defines a center-fired triac. A second silicon chip having regions defining a diac is bonded to the gate region of the triac chip. A copper layer of about 1 to 5 mils in thickness is bonded to the portions of the top major face of the triac chip that surround the gate region. Cathode, anode and gate connections are provided to the two-chip subassembly which is then encapsulated. The copper layer permits a smaller cathode connection to be made to the top of the triac chip without reducing the current capacity of the device. The triac device is mass-produced by first forming a plurality of triac chips in a two-dimensional array in a large area silicon wafer. The copper layers and diac chips are formed on the wafer prior to its separation into separate diac-triac chip subassemblies.