Patent · US Expired

Electrostatic chuck

US4502094A · kind A · utility

413Cited by
1References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 10, 1982
Grant dateFeb 26, 1985
Priority date
Expiry dateSep 10, 2002

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T279/23
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

An electrostatic chuck for holding a simiconductor wafer flat in a charged particle beam machine has thermally conductive portions for supporting the wafer. An electrically conductive member, for example a grid, has parts which extend between the thermally-conductive portions and is separated from the wafer by a dielectric layer. The wafer is clamped against the chuck by the electrostatic force set up across the dielectric layer when a potential difference is applied between the conductive wafer and the conductive member. Heat generated in the wafer by the bombardment of charged particles can be dissipated readily via the thermally conductive portions. The wafer can be electrically contacted at its back surface if the portions are also electrically conductive. To enhance thermal conduction away from the wafer, the conductive portions can protrude from the dielectric layer.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.