A method for fabricating a semiconductor device (100) comprises patterning a layer of photoresist material (111) to form a plurality of mandrels (124). The method further comprises depositing an oxide material (126) over the plurality of mandrels (124) by an atomic layer deposition (ALD) process. The method further comprises anisotropically etching the oxide material (126) from exposed horizontal surfaces. The method further comprises selectively etching photoresist material (111).
