Patent ID: 7279267

Claim:
A method for selectively planarizing a radiation sensitive polymer layer to improve a subsequent etchback process comprising the steps of: providing a substrate comprising a first density of semiconductor features and a second density of semiconductor features wherein said first density is greater than said second density; forming at least one radiation sensitive polymer layer having a first thickness topography to cover said semiconductor features; measuring a thickness of the first thickness topography; determining a radiant energy transmittance distribution based on said measured first thickness topography to produce a second thickness topography; exposing the at least one radiation sensitive polymer layer through a mask having said determined radiant energy transmittance distribution to selectively expose said polymer layer over said second density of semiconductor features to a different radiant energy dosage compared to said polymer layer over said first density of semiconductor features; developing the at least one radiation sensitive polymer layer to produce said second thickness topography wherein said second thickness topography covers said semiconductor features and has a higher degree of planarity than said first thickness topography; and, performing an etchback process of said second thickness topography to produce a third thickness topography having substantially uniform thickness.