Transistor-containing semiconductor device e.g. memory device

摘要

A semiconductor device (100) has a semiconductor substrate (1) bearing one or more transistors (T41-43) , each of which has a first conductivity type semiconductor layer formed on the substrate surface, a first conductivity type channel doping layer (103A-C) selectively formed in the semiconductor layer and a control electrode (4A-C) formed over the semiconductor layer at a position facing the channel doping layer. The control electrode has a polysilicon layer which contains a second conductivity type dopant and nitrogen, the nitrogen being introduced into the lower region of the polysilicon layer such that the dopant has a relatively high concentration in the upper region and a relatively low concentration in the lower region of the polysilicon layer. Also claimed is a similar device in which the transistor has an active region formed by a field oxide layer which is selectively formed on the substrate surface, an oxide layer formed on the active region and a control electrode a s described above formed on the oxide layer. Further claimed is a process for producing the above semiconductor device.