Method of edge doping SOI islands

摘要

SOI islands having doped edges are formed by providing over the surface of a layer of single crystalline silicon on an insulating substrate a masking layer formed of two layers, the lowermost layer adjacent the silicon layer being silicon oxide and the uppermost layer being silicon nitride. The masking layer is defined using standard photolithographic techniques and etching to form the masking layer over only the areas of the silicon layer which are to form the islands. The uncovered portion of the silicon layer is then removed by etching to form the islands. The lowermost layer of the masking layer is then etched laterally away from the edges of the island to expose a portion of the surface of the silicon layer adjacent the edges of the islands. After removing the uppermost layer of the masking layer, the exposed edge portions of the surface of the silicon layer are doped by ion implantation to form the islands with doped edges.