SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

PURPOSE:To obtain an integrated circuit device having no software error by forming the drain regions of two MOSTs which operate differentially near to each other, thereby being equally affected by the influence of incident alpha-ray. CONSTITUTION:The n type drain diffused regions 15, 16 of MOST 3 and 4 are formed near to each other. Even if alpha-ray is incident to the vicinity of the region 16, part of electrons e produced thereby is implanted to the region 16, but since the region 15 is disposed near at hand, the electrons e are implanted to the region 15. Accordingly, drain electrodes a, b are together lowered at their potentials. Even if is the alpha-ray is incident at the time tR, the potential A of the drain electrode a is lowered together with the potential B of the drain electrode b, no inversion occurs in the relation of high and low potentials, nor stored content of the memory cell can not be erroneously discriminated.