The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 12, 2015
Filed:
Mar. 07, 2011
Melissa Archer, San Jose, CA (US);
Melissa Archer, San Jose, CA (US);
AWBSCQEMGK, Inc., Sunnyvale, CA (US);
Abstract
Embodiments of the invention generally relate to a method for selectively etching or otherwise removing copper or other metallic contaminants from a substrate, such as a gallium arsenide wafer. In one embodiment, a method for selectively removing metallic contaminants from a substrate surface is provided which includes exposing a substrate to a peroxide clean solution, exposing the substrate to a hydroxide clean solution, and exposing the substrate to a selective etch solution containing potassium iodide, iodine, sulfuric acid, and water during a selective etch process. The substrate generally contains gallium arsenide material, such as crystalline gallium arsenide, and is usually a growth substrate for an epitaxial lift off (ELO) process. The copper or other metallic contaminants disposed on the substrate may be selectively etched at a rate of about 500 times, about 1,000 times, about 2,000 times, or about 4,000 times or greater than the gallium arsenide material.