Selective and anisotropic dry etching
AssigneeInternational Business Machines Corporation
InventorsSusanna R. Carbaugh, Hung Y. Ng, Murty S. Polavarapu, David Stanasolovich
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Abstract
A composition and method for anistropically etching polysilicon or silicides with excellent selectivity to an underlying layer of an oxide or nitride of silicon is disclosed. A mixture of CClF.sub.3 or CCl.sub.2 F.sub.2 and ammonia is employed at moderate pressures in a reactive ion etching chamber.
Claims26
An anisotropic gas plasma process carried out in a reactive ion etching mode using an etchant gas for selectively patterned etching of an elemental silicon-containing layer overlying a covalent silicon-containing layer, which layers form a surface of a semiconductor device, wherein the etchant comprises a gaseous chlorofluorocarbon capable of supplying CFx and chlorine ions in admixture with 20-65% of ammonia by volume at a pressure of from 60 to 100 millitorr.
An anisotropic gas plasma process carried out in a reactive ion etching mode using an etchant gas for patterned selective etching of an elemental silicon-containing layer overlying a covalent silicon-containing layer, which layers form a surface of a semiconductor device, wherein the etchant comprises CCl.sub.2 F.sub.2 in admixture with 20-65% of ammonia by volume at a pressure of 60 to 100 millitorr.
Dependencies are inferred from the claim text.