Method and apparatus for surface diagnostics
US4733073A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 16, 1986 |
| Grant date | Mar 22, 1988 |
| Priority date | — |
| Expiry date | May 16, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67242
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Method and apparatus for mass spectral analysis of unknown species of matter present on a surface even in extremely low concentrations. A probe beam such as an ion beam, electron beam or laser is directed to the surface under examination to remove a sample of material. An untuned, high-intensity laser is directed to a spatial region proximate to the surface. The laser has sufficient intensity to induce a high degree of nonresonant, and hence non-selective, photoionization of the sample of material within the laser beam. The non-selectively ionized sample is then subjected to mass spectral analysis to determine the nature of the unknown species.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.