Protective device for input

Abstract

Abstract PURPOSE:To divide an electric field applied between the resistance layer and wiring layer of the input protective device for a MOS type integrated circuit, and to prevent the accident of a short circuit between both layers by forming a conductor layer being brought to the state of electrical floating between the resistance layer and the wiring layer. CONSTITUTION:An insulating layer 14 is formed onto a semiconductor substrate 13, and the resistance layer 11 constituting a resistor R is formed into the layer 14. The wiring layer 12 and the resistance layer 11 are crossed mutually through the insulating layer 14. The conductor layer 15, which is formed by polysilicon and being brought to the state of electrical floating, is formed into the insulating layer 14. According to such constitution, capacitance among both the resistance layer 11 and the conductor layer 15 and both the conductor layer 15 and the wiring layer 12 is set to proper values. Consequently, the electric field is divided when surge voltage is applied to the resistance layer 11, and dielectric breakdown and the accidents of short circuits are made difficult to be generated between the resistance layer 11 and the wiring layer 12.

Inventors

• 👤 Hiroshi Iwahashi
• 👤 岩橋　弘
• 👤 Masamichi Asano
• 👤 正通 浅野

Bibliographic Details