Substrate clean solution for copper contamination removal
US9028620B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 7, 2011 |
| Grant date | May 12, 2015 |
| Priority date | — |
| Expiry date | Mar 7, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/7813
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.