Method for forming semiconductor device to prevent electric field concentration from being generated at corner of active region

摘要

A method for fabricating a field oxide layer capable of being applied to highly integrated circuits. The semiconductor device according to the present invention prevents electric field concentration at the corners of the active region, by filling a recess generated in a field oxide layer with an additional oxide spacer. The method includes the steps of a) forming a trench in a semiconductor substrate; b) forming an insulating layer on the resulting structure and burying the trench; c) forming a field oxide layer by controlling topology of the insulating layer in a wet etching process, wherein the wet etching process forms a recess at a corner of the field oxide layer so that a portion of sidewalls of the active region is exposed; d) forming an additional field oxide spacer layer at the recess in order to bury the exposed sidewall portion of the active region; and e) vertically growing an epitaxial layer on the exposed active region.