System for cushioning wafer in wafer carrier
US7059475B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 4, 2001 |
| Grant date | Jun 13, 2006 |
| Priority date | — |
| Expiry date | Dec 8, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67386
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The invention relates to transport and shipping containers for wafers that are processed into semiconductor units. The wafer transport system provides wafer carriers that provide damage protection and particulate protection with minimal contamination of the wafers in the shipper. The invention includes a wafer cushion for cushioning semiconductor wafers that is made of a closed-cell polyethylene material with a surface resistivity of less than 5×107 ohms per square that has less than 1800 ng/g Cl−, 400 ng/g F−/Acetate, 270 ng/g NO3−, 350 ng/g SO42−, and 60 ng/g PO43−ions leachable under moderate conditions. The wafer cushion optimally has no detectable outgassing organics under stringent conditions. The static control properties are the result of carbon that is part of the structure of the material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.