Element insulation region formation mfr. for semiconductor device

摘要

The method involves depositing on the device semiconductor substrate (1) an oxide film (21). A silicon layer (31) contg. a dopant impurity which prevents silicon crystallisation is formed on the oxide film. On the silicon layer is formed an oxidation resistant film. The oxidation resistant film is selectively removed to form an oxidation mask (4a) from it. The element insulation region is formed by oxidation of the silicon layer and the semiconductor substrate, using the mask. Pref. the oxidation resistant film is selectively removed by etching.