Mos type field effect transistor

Abstract

Abstract PURPOSE:To enable the precise positioning on the occasion of gate electrode formation of an MOS type field effect transistor by a method wherein a concave part is prepared at a portion on the surface of a substrate to form a high density impurity layer under a gate electrode. CONSTITUTION:A photoresist 24 is applied on the surface of a p-type silicon substrate 10, a window W is formed by patterning and the silicon substrate 10 is etched to form a concave H using the resist 24 as a mask. An impurity is ion-implanted to form a p<+>-type channel doping region 12. The resist 24 is removed and a gate oxide film 14 is formed. As the gate oxide film 14 encroaches on the surface of the channel doping region 12 to form a concave, it is used as a mark to perform positioning and the patterning of a gate electrode 20 and the gate oxide film 14 and the formation of source, drain regions 16, 18 are carried out.

Inventors

• 👤 Junji Sakurai

Bibliographic Details