Patent ID: 6686295
Filing Date: 2004-02-03
Classification: H01L

Abstract:
A method to anisotropically etch at least one layer in a group of layers consisting of a silicide layer, a polycrystalline silicon layer, and a polycide layer located over a layer of gate oxide on a substrate, said anisotropic etching producing a profile at or near 90Â° from horizontal in a parallel plate plasma etch reactor having a first electrode and an inert second electrode comprised of anodized aluminum, said method comprising:providing a gap of approximately 1.0 cm between said first electrode and said inert second electrode; mounting said substrate on said first electrode; providing a plasma atmosphere within said parallel plate plasma etch reactor, said plasma atmosphere including a pre sure of approximately 0.325 torr, Cl2 at a rate of approximately 90 sccm, H at a rate of approximately 70 sccm, and a plasma power density of approximately 0.57 W/cm2; and anisotropically etching said at leas one layer in said group of layers consisting of a silicide layer, a polycrystalline silicon layer, and a polycide layer located over said layer of gate oxide.