JPS6425480A - Mos type semiconductor device - Google Patents

Abstract

PURPOSE:To solve the deteriorations in an operation and reliability upon miniaturization of a MOS type semiconductor device and to reduce a deterioration mode intrinsic for an LDD structure by providing a sidewall gate electrode through a thin gate oxide film on the top of a low concentration diffused layer. CONSTITUTION:Sidewall gate electrodes 10, 11 are formed through thin gate oxide films 8, 9 on the tops of low concentration diffused layers 4, 5 of an LDD structure. Thus, the capacities of the films 8, 9 become larger than that of a gate oxide film 6 on the top of a channel, and parasitic resistances generated at the layers 4, 5 are reduced. Further, since the film 8 on the top of the layer 4 is thin, a point of inverting the direction of a surface electric field generated on the substrate surface of the layer 4 is disposed extremely toward a drain diffused layer 2 as compared with the LDD structure having a reverse T gate in a conventional LDD structure under bias condition that the implantation of hot carrier to the oxide film becomes maximum.