Semiconductor apparatus and method for fabricating the same

摘要

First, a substrate, on which a plurality of semiconductor devices is formed, is provided. Next, a first etching treatment is carried out to the substrate with a first etching gas comprising CF4 to form a base trench having a rounded-off upper edge or tapered upper edge. A second etching treatment is carried out to the substrate to form a trench region at the base trench so that the trench region has a rounded-off upper edge. And then, an insulating layer is formed on the substrate to fill up the trench region therewith.