Endpoint detection for chemical mechanical polishing using frequency or amplitude mode
US5644221A · kind A · utility
82Cited by
3References
18Claims
0Family size
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Key dates
| Filing date | Mar 19, 1996 |
| Grant date | Jul 1, 1997 |
| Priority date | — |
| Expiry date | Mar 19, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B7/105
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for endpoint detection in removal of a film from a semiconductor wafer is provided, with a sensor for creating a signal responsive to the film removal process, a positive feedback amplifier coupled to the sensor, the positive feedback amplifier having a mode selector, and an analyzer coupled to the positive feedback amplifier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.