Method of manufacturing a semiconductor device

Abstract

In a method of manufacturing a semiconductor device comprising a transistor having a gate insulated from a channel region at a surface of a semiconductor body by a gate dielectric, an active region of a first conductivity type is defined at the surface of the semiconductor body , and a patterned layer is applied consisting of refractory material, which patterned layer defines the area of the planned gate to be provided at a later stage of the process and acts as a mask during the formation of a source zone and a drain zone of a second conductivity type in the semiconductor body In a next step, a dielectric layer is provided in a thickness which is sufficiently large to cover the patterned layer, which dielectric layer is removed over part of its thickness by means of a material removing treatment until the patterned layer is exposed, which patterned layer is removed, thereby forming a recess in the dielectric layer at the area of the planned gate. Then, impurities are introduced via the recess into the channel region of the semiconductor body in a self-registered way by using the dielectric layer , as a mask and an insulating layer is applied, forming the gate dielectric, on which insulating layer a conductive layer is applied thereby filling the recess, which conductive layer is shaped into the gate of the transistor.