SEMICONDUCTOR STRIPS WITH UNDERCUTS AND METHODS FOR FORMING THE SAME

摘要

Provided is an integrated circuit device which includes a semiconductor substrate and a semiconductor strip extended into the semiconductor substrate. A first and a second dielectric region are arranged on the two opposite sides of, and in contact with, the semiconductor strip. Each of the first dielectric region and the second dielectric region includes a first portion whose level is the same with the semiconductor strip, and a second portion whose level is lower than the semiconductor strip. The second portion includes more portions overlapped with the semiconductor strip.