Method of manufacturing a semiconductor device having an SOI structure

摘要

In etching a polysilicon layer above a gate electrode layer, a portion of the gate electrode layer is left thereunder. The etching process of that polysilicon layer and that gate electrode layer is carried out in two steps of etching the polysilicon layer and an interlayer insulating layer, and etching the gate electrode layer and the gate oxide film. Therefore, the amount that is removed from an SOI layer can be suppressed in the manufacturing process thereof.