JPS5773975A - Mis type field effect transistor and manufacture thereof - Google Patents

Abstract

PURPOSE:To reduce the static capacity between a drain region and a gate electrode by introducing a part of a source region peripheral edge under a gate electrode when forming the source and drain regions in a semiconductor substrate disposed at both sides at the gate electrode but not introducing the peripheral edge of the drain region in nonsymmetric disposition. CONSTITUTION:A gate insulating film 2 is covered on an Si substrate 1, a gate electrode 3 is covered thereon, and ions are injected from a direction having an angle theta with respect to the vertical direction of the substrate 1. Since the surface of the electrode 3 is increased in height t at this time, a source forming region 60 of high impurity density is produced in self-aligning manner at the side near an ion source, and a drain forming region 50 of high density is isolated at a distance L' of tXtantheta at the side farther from the ion source. Thereafter, it is heat treated to introduce the part of the peripheral edge of the region 60 under the electrode 3 to form a source region 6, and the drain region 5 is not superposed with the electrode 3. In this manner, the static capacity of the region 5 side is reduced, thereby obtaining an MISFET having excellent characteristics.