Method and apparatus for monitoring and controlling wafer fabrication process
US6632321B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 5, 1999 |
| Grant date | Oct 14, 2003 |
| Priority date | — |
| Expiry date | Jan 5, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67253
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for monitoring, measuring and/or controlling the etch rate in a dry etch semiconductor wafer processing system. The wafer processing system has a monitoring assembly which comprises an electromagnetic radiation source and detector which interferometrically measures the etch rate. The actual rate of change of the etch as it progresses is measures by this technique and is compared to a model of a desired rate of change in a controller. The error between the actual rate of change and the desired rate of change is then used to vary at least one of the process parameters of the system in a direction tending to null the difference.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.