Method for producing flat wafer chucks
US6660975B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 2002 |
| Grant date | Dec 9, 2003 |
| Priority date | — |
| Expiry date | Aug 16, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49082
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods and structures are provided for extremely flat wafer chucks, allowing close thermal contact uniformly across a semiconductor processing substrate. An upper and a lower section are tightly fit to one another with flat inner surfaces in face-to-face contact. The sections also define at least one groove therebetween. The two sections have asymmetrical thickness, but the groove defined therebetween is correspondingly asymmetrical such that the groove is centered in the assembled chuck. A heater element, such as a resistive heater, is placed within the groove with some clearance prior to assembling the upper and lower sections. After assembly and tightening, the chuck is thermally cycled above the normal operating temperature prior to secondary machining, thus assuring flatness that is maintained during high temperature operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.