| 摘要 |
PURPOSE:To improve the small area ratio and the characteristics of a diode series circuit by providing an N-type layer on the collector of a lateral PNP transistor to form an NPN transistor. CONSTITUTION:An N-type island region 2 is formed on a P-type substrate 1, an emitter region 6 and a collector region 8 are formed to form a lateral PNP transistor Q1, and a base and a collector are connected by wirings 10. The collector region 8 of the Q1 is used as a base, and an N-type emitter region 101 is formed in the region 8 to form an NPN transistor Q2. Further, a P-type base region 11 and an N-type emitter region 12 are provided in the region 2 to form an NPN transistor Q3, the emitter 101 of the Q2 and the base 11 of the Q3 are connected by wirings 13 to be used as a diode series circuit. Then, since all the diodes are formed in the island 2, an occupying area is reduced. Since the lateral transistor is used, reverse dielectric strength becomes high, and all elements operate as transistors, thereby obtaining preferable diode characteristics. |
