Method and apparatus for releasing a semiconductor wafer from an electrostatic clamp
US5474614A · kind A · utility
49Cited by
2References
16Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 10, 1994 |
| Grant date | Dec 12, 1995 |
| Priority date | — |
| Expiry date | Jun 10, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05F3/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method and apparatus is provided for effectively releasing a semiconductor wafer (36) from a deactivated electrostatic clamp (20) by diffusing a neutralizing gas into the space between the clamping surface of the electrostatic clamp and the surface of the wafer, generating an ionizing voltage with an alternating polarity, and applying the alternating polarity ionizing voltage to the diffusing gas to neutralize the residual electrostatic charges remaining on the surfaces of the clamp (20) and the wafer (36).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.