| 摘要 |
<p>PURPOSE:To make a chip small-sized, to reduce the collector loss of an output- stage transistor and to enhance the incorporation property of a monolithic IC. CONSTITUTION:A second N<+> buried layer 15 in an IC part is formed in a P<-> type epitaxial layer 14 which is used to isolate a first N<-> buried layer 13 in an output-stage transistor(Tr) part 11, the output-stage Tr part and an IC part 10 in an N<+> substrate 12. The N<+> substrate in which the IC part is situated is etched until the P-layer 14 is exposed; a collector for the output-stage Tr part is formed. When the collector is taken out independently form the rear of a chip, a chip area becomes efficient and a collector resistance can be made small. The effective epitaxial thickness of the output-stage Tr part can be changed, and the breakdown strength of the Tr part can be increased. Since the collector of the Tr part is installed on the rear of the chip, a mounting operation which is applied to a flip-chip can be achieved.</p> |
