Patent ID: 7678704

Claim:
A method for forming a semiconductor device, the method comprising: forming an insulating layer over a conductive region; forming a silicon layer over the insulating layer; forming a pattern transfer layer over the silicon layer; removing portions of the pattern transfer layer to expose portions of the silicon layer, wherein remaining portions of the pattern transfer layer overlie the portions of the insulating layer in which contact holes will be formed; altering the exposed portions of the silicon layer such that the exposed portions of the silicon layer are distinct from unexposed portions of the silicon layer; removing the remaining portions of the pattern transfer layer; using an HF etch to remove portions of the silicon layer that were underlying the pattern transfer layer and not altered during the altering step, wherein portions of the insulating layer are exposed after the unaltered portions of the silicon layer have been removed; and etching the exposed portions of the insulating layer to form said contact holes.