Method for forming a contact opening with multilevel etching
US6010968A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 24, 1998 |
| Grant date | Jan 4, 2000 |
| Priority date | — |
| Expiry date | Dec 24, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31116
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A multilevel contact etching method to form a contact opening is provided. The method contains using an inductively coupled plasma (ICP) etcher to produce a high plasma density condition. The plasma gas etchant is composed of C.sub.4 F.sub.8 /CH.sub.2 F.sub.2 /CO/Ar with a ratio of 3:4:12:80 so that silicon nitride can be selectively etched while the silicon and silicide are not etched. Each content ratio of the plasma gas etchant allows a variance of about 20%. Wall temperature of the ICP etcher is about 100.degree. C.-300.degree. C. A cooling system for a wafer pad is about -20.degree. C.-20.degree. C. Chamber pressure is about 5-100 mtorr. Bias power on the wafer pad is about 1000 W-3000 W. Source power of an inductance coil is about 500 W-3000 W.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.