Microfeature wafer handling apparatus and methods
US5984391A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 1997 |
| Grant date | Nov 16, 1999 |
| Priority date | — |
| Expiry date | Jun 26, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S414/135
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The invention provides wafer handling apparatus for use with a wafer handling mechanism of the type that supports and transports wafers through and during semiconductor processes. Typically, the wafer has a first surface for semiconductor processing and a second surface having a surface finish with microfeatures therein. The invention utilizes at least three prongs extending from the mechanism and arranged to support the wafer. A stylus tip--preferably made from diamond--resides at a distal end of each prong. Each tip has a point that is smaller than at least some of the microfeatures of the second surface of the wafer such that the interaction of the tips with the microfeatures resists lateral movement of the wafer relative to the tips when the wafer rests on the tips by the force of gravity. This interaction is sufficient to move the wafer without substantial contribution from the coefficient of friction between the tips and the wafer. The invention solves the problems of the prior art associated with outgassing by rubber pads and low coefficients of friction associated with quartz pads. Motors with feedback control adjust the speed at which the prongs interact with the wafers so…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.