Hydrogen peroxide and acid etchant for a wet etch process
US6379577B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 10, 1999 |
| Grant date | Apr 30, 2002 |
| Priority date | — |
| Expiry date | Jun 10, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B2111/00853
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process and solution for selectively wet etching a titanium based perovskite material disposed on a silicon oxide or silicon nitride substrate is disclosed herein. The solution is composed of hydrogen peroxide, an acid and deionized water. The solution is heated to a temperature between 25 and 90 degrees Celsius. The titanium based perovskite material may be barium strontium titanate, barium titanate, strontium titanate or a lead titanate. The solution selectively etches the perovskite material while the substrate is only minimally etched, if at all. The process and solution allows for an etching rate up to thirty times greater than conventional etching rates for similar perovskite materials selective to various substrate, barrier and mask layers, including SiO2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.