Electrostatic protective circuit for complementary-metal oxide semiconductor-integrated circuit

Abstract

Abstract PURPOSE:To prevent the lowering of electrostatic dielectric resistance in the CMOSIC, and to obtain a predetermined protective effect by forming a diode for protecting static electricity connected to a pad electrode in P<+>P<->N<-> structure by utilizing a well diffusion process. CONSTITUTION:A P<-> diffusion layer 9 is shaped previously in a protective diode preparing region of an N<-> substrate in a forming process for a P<-> well in a manufacturing process for the CMOSIC. A P<+> layer 7 is shaped in the region 9 while being stacked on the P<-> region 9 in a forming process for a P<+> diffusion layer, and the pad electrode 4 connected to an end section of the P<+> layer 7 is shaped in a forming process for electrode wiring. The dielectric resistance can be improved and made constant as compared to a case that only a conventional P<+> diffusion layer is used by employing the P<+>P<->N<-> diode manufactured by these diffusion layers and the N<-> substrate as the electrostatic protective circuit for the CMOSIC.

Inventors

• 👤 Naoyuki Morita

Bibliographic Details