Patent ID: 7563675
Filing Date: 2009-07-21
Classification: H01L

Abstract:
1. A method of word line etching, comprising the steps of: (a) patterning a word line; (b) depositing a layer of polysilicon over said word line; (c) depositing a layer of bottom antireflective coating (BARC) material over said layer of polysilicon; (d) etching said BARC layer and said polysilicon layer using a ladder etch, said ladder etch removing the BARC layer and a portion of said polysilicon layer; (f) depositing a dielectric layer on a top surface of the etched polysilicon layer; and (g) applying a mask layer over said dielectric layer and etching at least one feature into said polysilicon layer; wherein said ladder etch comprises a series of breakthrough etch steps and soft landing etch steps.