Patent ID: 7759239
Filing Date: 2010-07-20
Classification: H01L

Abstract:
1. A method of fabricating a semiconductor device comprising: forming a gate layer over a semiconductor substrate; forming a hard mask layer over the gate layer; forming a first material layer over the hard mask layer; forming a patterned photoresist layer having a first opening over the first material layer; removing a portion of the first material layer beneath the first opening through a processing cycle including: repeating the processing cycle until the hard mask layer is exposed by a second opening in the first material layer, the second opening being formed in a last processing cycle and smaller than the first opening; etching a portion of the hard mask layer beneath the second opening to expose the gate layer; and patterning the gate layer using the hard mask layer; wherein a first etching selectivity of the first and second material layers is smaller than a second etching selectivity of the second material layer and the photoresist layer.