| 摘要 |
PURPOSE:To reduce cost, and to prevent the degradation of integration while avoiding the mutual complication of wirings by using a diode forming region and a collector region as two regions of diodes, mutually connecting both input step and output step transistors and the diodes and inhibiting the area of a semiconductor substrate to the necessary minimum of the demand. CONSTITUTION:P<+> type base regions 8, 12 and a P<+> type region 16 for forming the diode are formed simultaneously through a base diffusion process for a semiconductor integrated circuit, and N<+> type emitter regions 9, 13 and an N<+> type region 17 are formed simultaneously through an emitter diffusion process. Accordingly, the input step transistor, the output step transistor and the diode are formed, a contact window is bored to an insulating film 18 coating the upper section of the silicon substrate, and electrodes 19-25 being in ohmic-contacting with the collector, base and emitter regions of both transistors and the P<+> type region as the anode region of the diode are formed. The collector electrode 19 of the input step transistor, the anode electrode 25 of the diode, the emitter electrode 21 of the input transistor and the base electrode 23 of the output step transistor are each connected mutually by mutual wiring layers. |
