Prevention of electrostatic wafer sticking in plasma deposition/etch tools
US7030035B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 2004 |
| Grant date | Apr 18, 2006 |
| Priority date | — |
| Expiry date | May 14, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/6831
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
To remove unwanted electrostatic charge from a substrate or substrate clamping mechanism in a plasma processing chamber following the plasma processing of the substrate, the process of shutting down the RF power supply is altered. Specifically, the present invention is a stepped RF power shut down sequence in which the RF power is lowered in a first step from full power to approximately 5 to 10 watts for a short period of time, such as approximately 1 second, and thereafter the RF power is turned off. As a result of this RF power shut down sequence, with its intermediate step, the plasma during the intermediate step acts to neutralize or discharge the electrostatic charge that has built up upon the wafer and/or clamping mechanism during full power operation. When the electrostatic charge has been removed, the wafer sticking problem is resolved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.