Process of increasing screen dielectric thickness

摘要

A method of forming a semiconductor device using shallow trench isolation, includes forming a trench within a semiconductor substrate and forming a screen dielectric stack outwardly from the semiconductor substrate. The screen dielectric stack includes a first sacrificial dielectric layer disposed outwardly from the semiconductor substrate and a second sacrificial dielectric layer disposed outwardly from and in contact with the first sacrificial dielectric layer. In one embodiment, the first sacrificial dielectric layer is formed before forming the trench and the second sacrificial dielectric layer is formed after forming the trench.