Perimeter wafer seal
US4932358A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 18, 1989 |
| Grant date | Jun 12, 1990 |
| Priority date | — |
| Expiry date | May 18, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C16/4588
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A seal ring presses against a wafer on a CVD chuck continuously around the outer periphery of the wafer, and with sufficient force to hold the backside of the wafer against the chuck, so no CVD material may deposit on the backside of the wafer. The seal ring has one surface for contacting the frontside of the wafer and a second surface that extends close to the CVD chuck, so the edge of the wafer is also excluded from CVD coating. With use of the wafer seal ring apparatus and method, CVD coating is confined to the frontside of a wafer. In a preferred embodiment, an apparatus with a slide operated by a cam lever and a tension spring for moving the seal ring and pressing it against a wafer on a CVD chuck is used with each of multiple chucks attached to a rotatable turret within a CVD chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.