METHOD OF FORMING SOI SUBSTRATE AND THE SUBSTRATE SO FORMED

摘要

A method for forming an SOI(silicon on insulator) substrate is provided to securely prevent a leakage current by forming a thermal oxide layer on a semiconductor substrate so that an oxygen density is uniform in an oxide layer. A thermal oxide layer is formed on a semiconductor substrate(1). While the thermal oxide layer is patterned to form a thermal oxide layer pattern(3a), a part of the semiconductor substrate is exposed. A first semiconductor single crystalline layer(4d) is formed, covering the sidewall and the upper surface of the thermal oxide layer pattern and coming in contact with the exposed semiconductor substrate. A second semiconductor single crystalline layer(4e) is formed on the first semiconductor single crystalline layer. A heat treatment is performed on the first semiconductor single crystalline layer. A etch process for planarization is performed to eliminate a part of the upper part of the first semiconductor single crystalline layer.