Patent ID: 8062980

Claim:
A method of fabricating a semiconductor device, comprising: forming a core material on a workpiece, the forming the core material including: forming a material film of the core material on the workpiece, removing a predetermined portion of the material film and a portion of the workpiece located immediately under the predetermined portion of the material film, and applying a slimming process to the material film from which the predetermined portion thereof has been removed, so as to form level differences in regions of the workpiece exposed on both sides of the core material by forming the core material; forming a coating film comprising an amorphous material so as to cover an upper surface and side faces of the core material; crystallizing the coating film by applying heat treatment; forming a sidewall mask on the side faces of the core material and on the level differences in regions of the workpiece by removing the crystallized coating film while leaving a portion thereof located on the side faces of the core material; removing the core material after forming the sidewall mask; and etching the workpiece using the sidewall mask as a mask after removing the core material.