Process for etching high copper content aluminum films
AssigneeApplied Materials, Inc.
InventorElaine A. Webb
Life of this patent
Estimating the term…
Abstract
Aluminum alloys containing high amounts of copper can be etched to eliminate copper residues using boron trichloride and chlorine under etch conditions of low temperature, low pressure, high power and strict control of the amount of nitrogen present.
Claims9
A method for reactive ion etching of an aluminum alloy containing over about 0.5% of copper on a substrate which comprises etching with a precursor gas including boron trichloride and chlorine at temperatures below about 80.degree. C. while regulating the nitrogen content of the precursor gases to prevent formation of a copper residue on the substrate.
A method of reactive ion etching an aluminum layer containing about 1% by weight of copper on a substrate using boron trichloride and chlorine as the etch gases at a maximum temperature of about 100.degree. C. comprising regulating the amount of nitrogen carrier gas during etching so that formation of a copper residue on the substrate is avoided.
A method of reactive ion etching an aluminum layer containing about 2% by weight of copper on a substrate using boron trichloride and chlorine as the etch gases at a maximum temperature of about 100.degree. C. comprising etching by regulating the amount of nitrogen present so that formation of a copper residue on the substrate is avoided.
Dependencies are inferred from the claim text.