Patent ID: 8921193
Filing Date: 2014-12-30
Classification: H01L

Abstract:
1. A method of forming a semiconductor structure, the method comprising: forming trench isolation regions extending from a top surface of a semiconductor substrate into the semiconductor substrate, wherein the trench isolation regions define a first active region and a second active region; forming a first gate dielectric over the semiconductor substrate in the first active region; forming a convex surface of the top surface of the semiconductor substrate in the second active region by performing a hydrogen anneal on the semiconductor substrate in an ambient containing hydrogen while the top surface of the semiconductor substrate in the second active region is exposed, the convex surface being between a first source/drain region of the second active region and a second source/drain region of the second active region, a curvature of the convex surface being convex in a direction from the first source/drain region to the second source/drain region; and forming a second gate dielectric over the convex surface in the second active region.