Patent ID: 8153527

Claim:
A method for fabricating a semiconductor device comprising: forming a first device layer over a substrate and a second device layer over the first device layer; forming a patterned masking layer of photoresist material on the second device layer; forming a patterned second device layer, using the patterned masking layer of photoresist material, with second sidewalls that are outwardly tapered by isotropically etching portions of the second device layer; etching the first device layer in accordance with the patterned second device layer to form a patterned first device layer; and wherein etching the first device layer comprises a main etch step and an over-etch step, the main etch step being configured to simultaneously remove exposed portions of the first device layer to define a shape of the patterned first device layer and at the same time trim etch residues deposited on the tapered sidewalls of the patterned second device layer during the etching of the first device layer.