SEMICONDUCTOR DEVICE AND METHOD FOR FORMING THE SAME

摘要

In order to prevent formation of voids in STI film, after a second buried insulating layer is filled and planarized, a high density cap is formed embedded in the center region of the second buried insulating layer of the STI trench. The high density cap shields and protects the weaker center region of the second buried insulating layer of the STI trench from the subsequent processing steps and prevents formation of voids in the second buried insulating layer.