INTEGRATED CIRCUIT DEVICE

摘要

PURPOSE:To prevent a gate protection element from causing breakdown easily by making the interval between a protection circuit element and a high-density impurity region sufficient in the gate protection circuit of an integrated circuit. CONSTITUTION:Insulating gate FET 15 and transistor protection region 17 which prevents the destruction of this FET 15 are formed on N-type semconductor substance 14. Protection region 17 is connected between signal input terminal 16 and gate electrode 15a. Then, N-type high-density region 18 is formed around protection region 17. Interval C between regions 17 and 18 is made larger than interval D between FET 15 and region 18. Since interval D becomes very small in case that the device is constituted densely, C>D is defined because the dielectric strength of source 15s, drain 15D and substance 14 is lowered up to several 10V.