Wafer support with electrostatic discharge bus
US6239963A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 21, 1999 |
| Grant date | May 29, 2001 |
| Priority date | — |
| Expiry date | Jun 21, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67313
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A wafer support featuring a polymer rack formed of parallel, spaced apart comb structures with spaced apart teeth into which wafers can loosely fit and a shank immediately below the teeth which is connected to lifter shafts. A conductive polymer bus bar runs along the shank less than a millimeter below the base of the teeth. The polymer rack will fit through a standard size wafer cassette for wafer transfer. The bus bar is connected to electrical ground, found at metal lifter shafts, by means of conductive polymer cross bars. The bus bar is close enough to one or more wafers to allow arcing from the wafer to the bus bar and then to ground when a wafer becomes highly charged with electrostatic charge, thereby discharging the wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.