Direct etch for thin film resistor using a hard mask
US5547896A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 1995 |
| Grant date | Aug 20, 1996 |
| Priority date | — |
| Expiry date | Feb 13, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/136
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
In a method of etching a thin film resistor material, such as NiCr or CrSi, and of producing a thin film resistor, a non-photoresist hard mask is deposited on an exposed surface of thin film resistor material, a delineated portion of the hard mask is etched with a hydrogen peroxide etchant that does not affect the thin film resistor material to expose the material therebeneath, and the exposed thin film resistor material is etched with a second etchant that does not affect the hard mask. The second etchant may be sulfuric acid heated to greater than 125.degree. C. for NiCr or a mixture of phosphoric acid, nitric acid and hydrofluoric acid for CrSi. The hard mask preferably comprises TiW.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.