Microanalysis by pulse laser emission spectroscopy
US4259574A · kind A · utility
16Cited by
4References
18Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 6, 1979 |
| Grant date | Mar 31, 1981 |
| Priority date | — |
| Expiry date | Nov 6, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/6408
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system for detecting and identifying the composition of a material, such as semiconductor wafers and chips, subject to one or more stages of processing. The material is laser irradiated to induce molecular fluorescence with means to detect the decay rate of the fluorescence. The decay rate is then compared with a decay record of fluorescence of acceptable modifications of the material, inclusive of amalgamated contaminants or impurities (e.g. doped regions) to determine the state of the modification of the material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.