Method of selectively etching titanium-containing materials on a semiconductor wafer using remote plasma generation
US5326427A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 11, 1992 |
| Grant date | Jul 5, 1994 |
| Priority date | — |
| Expiry date | Sep 11, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/32136
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of selectively etching titanium-containing materials without attacking aluminum or silicon dioxide is describe, wherein an atomic chlorine etching environment is generated using downstream techniques. Atomic chlorine in the absence of ion bombardment (as provided by downstream etching) etches titanium-containing materials such as titanium nitride without attacking silicon dioxide. In one embodiment of the invention, atomic chlorine is generated by the discharge of energy into molecular chlorine. In another embodiment of the invention, discharge of energy into a fluorine-containing gas causes the generation of atomic fluorine. Molecular chlorine is then added, creating a fluorine-chlorine exchange reaction which produces atomic chlorine. The presence of fluorine inhibits etching of aluminum, but does not impede the etching of titanium-containing materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.