SUBSTRATE STRUCTURE OF SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME

摘要

A substrate structure utilized to fabricate a semiconductor device is constituted by a silicon substrate; an element region selectively formed on the silicon substrate and a relatively thick field oxide region formed adjacent to the element region; an element isolating region formed between the element region and the field oxide region, the element isolating region being in direct contact with the field oxide region; the element isolating region being provided with a relatively deep groove formed in the silicon substrate and having a relatively small width; a silicon oxide insulating film formed on the inner wall of the groove; and a silicon nitride insulating film disposed on the silicon oxide insulating film. The surfaces of the element region, the element isolating region and the field oxide region on the silicon substrate are formed substantially flat. With this substrate structure the element isolating characteristic can be improved so that integrated circuits at a higher density than the prior art can be obtained.