Patent ID: 7332405
Filing Date: 2008-02-19
Classification: H01L

Abstract:
1. A method of fabricating a semiconductor device, comprising: preparing a substrate having a supporting layer, an insulator layer disposed on the supporting layer, and a semiconductor layer disposed on the insulator layer, the substrate including a first area for formation of circuit elements and a second area for formation of an alignment mark adjacent the first area; forming a nitride film on the substrate in the first area and the second area; patterning the nitride film to form a first opening in the nitride film partially exposing the substrate in the first area, and a second opening in the nitride film in the second area; locally oxidizing the semiconductor layer below the first opening to form an isolation region in the first area and below the second opening in the second area; and removing the oxidized semiconductor layer below the second opening to form the alignment mark, wherein the alignment mark is defined by edges of the semiconductor layer remaining after said removing, said removing being performed while the edges are protected by the nitride film.