Exclusion guard and gas-based substrate protection for chemical vapor deposition apparatus
US5769951A · kind A · utility
Inventors
Key dates
| Filing date | Jan 17, 1996 |
| Grant date | Jun 23, 1998 |
| Priority date | — |
| Expiry date | Jan 17, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/68785
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A platen supports a wafer during the deposition of tungsten, metal nitrides, other metals, and silicides in a chemical vapor deposition reactor. A deposition control gas that includes a suitable inert gas such as argon or a mixture of inert and reactant gases such as argon and hydrogen is introduced through a restrictive opening into an ambient in the reactor. An exclusion guard aligned with the platen has an extension extending over a frontside peripheral region of the wafer. Deposition control gas is introduced under the exclusion guard extension and exits through a restrictive opening between the exclusion guard extension and a wafer frontside peripheral region. The restrictive opening provides a uniform pressure of deposition control gas at the edge and frontside of the wafer to prevent deposition on the wafer edge and backside.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.