Patent ID: 6121154
Filing Date: 2000-09-19
Classification: G03F,H01L

Abstract:
A method for etching a nitride photoresist-underlying layer, the method comprising the steps of:providing a substrate having thereon a nitride photoresist-underlying layer and a photoresist mask overlying said photoresist-underlying layer;treating, using a chlorine-based plasma, said photoresist mask in a plasma processing chamber, said treating being configured to etch at least a portion of said photoresist mask and to deposit passivation polymer on vertical sidewalls of said photoresist mask, said chlorine-based plasma being generated from an etchant source gas, said etchant source gas consisting essentially of a member of the group consisting of Cl.sub.2, Cl.sub.2 /He, Cl.sub.2 /HBr, Cl.sub.2 /HBr/He, and Cl.sub.2 /N.sub.2 ; andafter said treating, etching said photoresist-underlying layer in a subsequent etching process using said photoresist mask.