Composite type power transistor

Abstract

Abstract PURPOSE:To manufacture the composite type transistor for an amplitude control circuit easily, and to decrease the variance of characteristics by separating a transistor and a diode formed on a chip by shaping a separating groove reaching a collector layer of the substrate. CONSTITUTION:The triple diffusion NPN transistor is prepared to the N type substrate, one part of a P base layer 3 is etched chemically and the groove reaching the collector high resistance layer 1 is shaped, and the layer 3 is separated from the second base region 4. A film such as a glass protective film 6 is formed in the groove, a substance such as Al is evaporated and each electrode 7-9 of the transistor and a diode electrode 10 are shaped, and the composite type transistor is molded. Accordingly, the transistors having uniform inverse recovery characteristics can be prepared while connecting wiring can be unnecessitated because the transistor and the diode are formed simultaneously on the same chip. The structure can also apply easily to a Darlington connection type transistor for high power.

Inventors

• 👤 Masahiko Aoki
• 👤 Motofumi Miyazaki

Bibliographic Details