Patent ID: 7332387

Claim:
A method of fabricating a MOSFET device, comprising: forming a gate structure on a substrate, said gate structure comprising a gate dielectric layer and a conductive layer; forming a masking layer to cover said gate structure and the substrate; directing implant ions onto said masking layer at an angle so as to shield part of said masking layer against the ions; selectively etching the ion implanted part of said masking layer so as to expose a side of said gate structure and a region of a surface of the substrate adjacent to the side; performing an oxidation process on part of the exposed side of said gate structure, such that a bottom corner of the exposed gate structure is oxidized to form a bird's beak structure; removing said masking layer; and forming a source region and a drain region in the substrate respectively adjacent to two sides of said gate structure, wherein said drain region is adjacent to said bird's beak structure and the exposed side.