Patent ID: 7687403

Claim:
A method of manufacturing a flash memory device, the method comprising: providing a substrate having an insulating layer, a first mask layer over the insulating layer, a second mask layer over the first mask layer, a first photoresist pattern over the second mask layer, the first photoresist pattern having a first pitch; forming a material layer over the first photoresist pattern and the second mask layer, wherein the material layer is formed of inorganic material or of organic material containing silicon; removing an upper portion of the material layer to expose the first photoresist pattern to form a material layer pattern having a second pitch that is less than the first pitch; removing the exposed first photoresist pattern; etching the second hard mask layer using the material layer pattern to form a second hard mask layer pattern that extends along a first direction; forming a second photoresist pattern defining a first region that is not exposed and a second region that is exposed, the second region extending along a second direction that is orthogonal to the first direction; etching the first hard mask layer using the second photoresist pattern to form a first hard mask layer pattern having an angular shape; and etching the insulating layer using the first hard mask layer pattern to form a contact hole having an angular shape that expose material underlying the insulating layer.