Apparatus for maintaining wafer back side and edge exclusion during supercritical fluid processing
US6550484B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 7, 2001 |
| Grant date | Apr 22, 2003 |
| Priority date | — |
| Expiry date | Dec 7, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67126
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The present invention pertains to apparatus and methods for maintaining wafer back side, bevel, and front side edge exclusion during supercritical fluid processing. Apparatus of the invention include a pedestal and an exclusion ring. When the exclusion ring is engaged with the pedestal a channel is formed. A reactant-free supercritical fluid is passed through the channel and over a circumferential front edge of a wafer. The flow of reactant-free supercritical fluid protects the bevel and circumferential front edge of the wafer from exposure to reactants in a supercritical processing medium. The back side of the wafer is protected by contact with the pedestal and the flow of reactant-free supercritical fluid. Exclusion rings of the invention, when engaged with their corresponding pedestals make no or very little physical contact with the wafer front side.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.