Method and apparatus for improved retention of a semiconductor wafer within a semiconductor wafer processing system
US5880923A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 9, 1997 |
| Grant date | Mar 9, 1999 |
| Priority date | — |
| Expiry date | Jun 9, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T279/23
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Method and apparatus for retaining a semiconductor wafer upon a pedestal within semiconductor wafer processing equipment. An electrostatic chuck contains a wafer support having a surface. Embedded beneath the surface is a number of electrodes defining a number of chucking zones. The electrodes are energized by a number of non-zero voltages thereby creating a variable, non-zero chucking force in each of the chucking zones. The method of retaining a substrate to a substrate support consists of biasing at least one of the electrodes with a first voltage of a first magnitude and biasing each previously unbiased electrode with a voltage of unequal magnitude of the initially biased electrode and every other previously unbiased electrode such that a non-zero chucking force exists in every zone. Wafer chucking zones of differing force improve uniformity of heat transfer gas layer distribution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.