Etchant for selectively etching copper and copper alloy, and method for manufacturing semiconductor substrate using said etchant
US11821092B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 2019 |
| Grant date | Nov 21, 2023 |
| Priority date | — |
| Expiry date | May 27, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2224/13155
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An etchant capable of selectively etching copper and a copper alloy while suppressing dissolution of nickel, tin, gold, and an alloy thereof. The etchant contains: (A) 5-10.5% by mass of hydrogen peroxide with respect to the total mass of the etchant; (B) 0.3-6% by mass of nitric acid with respect to the total mass of the etchant; (C) at least one nitrogen-containing 5-membered ring compound selected from triazoles and tetrazoles, which may have at least one substituent selected from a C1-6 alkyl group, an amino group, and a substituted amino group having a substituent selected from a C1-6 alkyl group and a phenyl group; and (D) (d1) one or more pH adjusters selected from an alkali metal hydroxide, ammonia, an amine, and an ammonium salt, (d2) a phosphoric acid compound, or (d3) a combination of (d1) and (d2).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.