Metal etch rate analyzer
US4260259A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 29, 1978 |
| Grant date | Apr 7, 1981 |
| Priority date | — |
| Expiry date | Dec 29, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/0675
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved interferometer system for detecting the etch rate of an opaque material, such as silicon or metal. The system includes means for producing two parallel beams of light, with one beam being directed to the surface of the opaque material, and the other beam being directed to the surface of an adjacent masking material of transparent nature. The rate of etch of the opaque material is detected from the interference pattern changes between the first beam and the second beam. The system utilizes a novel arrangement of beam splitters which results in equal path lengths for the respective beams and further includes a viewing light which is passed by a system of dichroic filters to enable observation of the focus spot.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.