Reducing backside deposition in a substrate processing apparatus through the use of a shadow ring
US5476548A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 1994 |
| Grant date | Dec 19, 1995 |
| Priority date | — |
| Expiry date | Jun 20, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/6838
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A substrate processing apparatus for processing a substrate having a peripheral edge, an upper surface for processing and a lower surface lying on a support. The apparatus includes a processing chamber which houses the substrate support, in the form of a heater pedestal including a substrate receiving surface for receiving the lower surface of the substrate. A circumscribing shadow ring is located around the pedestal to cover peripheral edge portion of the substrate. The shadow ring also defines a cavity, between itself and the pedestal, at the peripheral edge of the substrate. In operation, the chamber receives processing gas at a first pressure and purge gas is introduced into the cavity, between the ring and the pedestal, at a second pressure which is greater than the first pressure. Fluid conduits are provided to enhance the flow of the purge gas away from the peripheral edge of the substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.