Method of fabricating semiconductor device

摘要

In a method of fabricating a semiconductor device, a plurality of MOS devices are formed on a semiconductor substrate each with a source, a drain, and a gate electrode. A first insulating layer is formed on the semiconductor substrate with the MOS devices. A moat pattern is formed on the first insulating layer such that the portions of the first insulating layer placed at device isolation areas are exposed to the outside. Trenches are formed at the semiconductor substrate through etching the first insulating layer and the underlying semiconductor substrate using the moat pattern as a mask. The semiconductor substrate is partially etched by a predetermined depth. The trenches are filled up through forming a second insulating layer on the etched portions of the semiconductor substrate, and on the first insulating layer.