Method and apparatus for calibrating optical path degradation useful for decoupled plasma nitridation chambers
US9865438B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 22, 2011 |
| Grant date | Jan 9, 2018 |
| Priority date | — |
| Expiry date | Oct 23, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/2482
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods for matching semiconductor processing chambers using a calibrated spectrometer are disclosed. In one embodiment, plasma attributes are measured for a process in a reference chamber and a process in an aged chamber. Using a calibrated light source, an optical path equivalent to an optical path in a reference chamber and an optical path in an aged chamber can be compared by determining a correction factor. The correction factor is applied to adjust a measured intensity of plasma radiation through the optical path in the aged chamber. Comparing a measured intensity of plasma radiation in the reference chamber and the adjusted measured intensity in the aged chamber provide an indication of changed chamber conditions. A magnitude of change between the two intensities can be used to adjust the process parameters to yield a processed substrate from the aged chamber which matches that of the reference chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.