Patent ID: 7972957
Filing Date: 2011-07-05
Classification: H01L

Abstract:
1. A method of making a semiconductor device comprising: forming a first sacrificial layer over a first layer to be etched, the first sacrificial layer having a plurality of openings formed therethrough, each opening exposing a top portion of the first layer to be etched at the bottom of each opening; forming a first photoresist layer over the first sacrificial layer and filling the plurality of openings formed through the first sacrificial layer; forming a plurality of openings in the first photoresist layer, each one of the plurality of openings in the first photoresist layer individually overlying at least one of the openings in the first sacrificial layer and wherein each opening in the first sacrificial layer has a smaller cross-sectional area than the cross-sectional area of the overlying opening in the first photoresist layer; and etching the first layer to be etched through the openings in the first photoresist layer and the first sacrificial layer, comprising exposing the first layer to be etched to an etching material; wherein the first sacrificial layer comprises a photoresist material that has been treated to increase the resistance of the photoresist material to etching by the etching material; and wherein the sizes of the openings in the first sacrificial layer remain substantially unaffected after etching of the first layer to be etched through the openings in the first photoresist layer and the first sacrificial layer.