MANUFACTURING METHOD OF INSULATING LAYER FOR ISOLATION

摘要

The method for forming insulating layer for element separation comprises the steps of forming a trench over a silicon substrate and depositing a thermal oxide layer, a nitride layer and a BPSG layer over the whole surface; making the BPSG layer flat, ion-implanting a silicon germanium atom and forming an amorphous layer over the surface of the BPSG; removing the amorphous layer and the BPSG layer and forming a TEOS layer over the upper portion of the whole structure; and etching back the TEOS layer until the upper portion of the nitride layer is exposed, filling the trench with the thermal oxide layer, nitride layer, BPSG layer, amorphous layer and TEOS layer and forming an insulating layer for element separation.