Patent ID: 7659163
Filing Date: 2010-02-09
Classification: H01L

Abstract:
1. A method of forming a semiconductor device, comprising: providing a substrate including at least four protrusions projecting from said substrate, said at least four protrusions being arranged as a quadrangle to define a diagonal direction; forming a silicon layer above said substrate and each protrusion; performing an ion implanting along said diagonal direction to form an implanted region and a non-implanted region in said silicon layer; performing an anisotropic etching to transform said silicon layer into a silicon spacer positioned on a side wall of each protrusion; forming a first oxide layer over said non-implanted region in said silicon spacer and a second oxide layer over said implanted region in said silicon spacer, said first oxide layer being thicker than said second oxide layer; etching said second oxide layer; and etching said substrate by using said first oxide layer as a mask to form a recess in said substrate.