Patent ID: 6420240
Filing Date: 2002-07-16
Classification: H01L

Abstract:
A method for reducing the step height of a shallow trench isolation structure, said method comprising the acts of:(a) forming a mask on a substrate; (b) forming a trench in said substrate; (c) filling said trench with a dielectric material; (d) planarizing said dielectric material a first time to a level approximately coplanar with an upper surface of said mask; (e) planarizing said dielectric material a second time to a level approximately coplanar with an upper surface of said substrate; and (f) forming overlying layers on said dielectric material; wherein act (d) is by chemical mechanical planarization and act (e) is by an etch back process and further comprising the act of replacing a hard mask used to define said trench with a resist mask before performing act (e).