Patent ID: 6242362
Filing Date: 2001-06-05
Classification: H01L

Abstract:
A method for fabricating a vertical hard mask/conductive pattern profile comprising the steps of:a) providing a substrate having a conductive layer there over; said conductive layer comprising polysilicon;b) forming a hard mask layer on said conductive layer; said hard mask layer being composed of silicon oxynitride;c) patterning said hard mask layer to form a hard mask pattern; andd) etching said conductive layer using Cl.sub.2, a He--O.sub.2 mixture, and N.sub.2 to form a conductive pattern wherein the Cl.sub.2 to He--O.sub.2 mixture flow rate ratio is between about 30 and 60, the Cl.sub.2 to N.sub.2 flow rate ratio is between about 20 and 40, and the He--O.sub.2 mixture is between 80% He and 85% He by volume.