Patent ID: 6624068
Filing Date: 2003-09-23
Classification: H01L

Abstract:
A method for fabricating polysilicon structures on a semiconductor substrate including the steps of:a) depositing a polysilicon layer on the substrate; b) depositing on the polysilicon layer an antireflective coating comprising a bilayer of inorganic films having thicknesses, extinction coefficients, and refractive indices which allow less than 1% reflection radiation at a wavelength of about 193 nm, said bilayer comprising a first or bottom layer and a second or top layer; c) depositing a photoresist over the antireflective coating; d) exposing selected portions of the photoresist to radiation of about 193 nm wavelength; e) developing the photoresist to create a resist mask defining and protecting portions of said anti-reflective coating; f) patterning said bilayer antireflective coating to form a hard mask, thereby exposing selected areas of said polysilicon; g) removing the photoresist; h) etching to remove the exposed polysilicon, i) etching to remove the second or top layer of anti-reflective hard mask; and j) removing the first or bottom layer of hard mask simultaneously with the polysilicon clean-up process.