In-situ automated contactless thickness measurement for wafer thinning
US6437868B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 28, 1999 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Oct 28, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T279/11
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A system for measuring the thickness of a wafer while it is being thinned this disclosed. The system and method provide integrating an optical reflectometer into a common wafer thinning apparatus. Using reflected optical signals from the top and bottom of the wafer, the thickness of the wafer is determined with time based calculations in real-time while thinning is occurring. Once the desired thickness has been reached, the thinning operation is halted. By performing the measurement in-situ, this system and a method prevent scrapping of wafers which are overthinned and the reloading of wafers which are too thick. Since an optical reflectometer is used, the measurement is contactless, and thus prevents possible damage to wafers during measurement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.