Method of and apparatus for measuring film thickness
US5120966A · kind A · utility
116Cited by
7References
3Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Feb 6, 1991 |
| Grant date | Jun 9, 1992 |
| Priority date | — |
| Expiry date | Feb 6, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/0616
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Light in the ultraviolet region is applied toward a transparent thin film of an object sample to measure energy of light reflected by the object sample. On the basis of the measured energy value, the thickness of the transparent thin film on the object sample can thus be correctly measured even if the film thickness is not more than 10 nm. In the preferred embodiment, an optical system is included to enable monitoring of a position of the thin transparent film. In one aspect of the invention visible light reflected from the transparent film is used to form an image to facilitate such monitoring.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.