Method for detection of chemicals by reversible quenching of silicon photoluminescence
US5338415A · kind A · utility
26Cited by
5References
7Claims
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Key dates
| Filing date | Jun 22, 1992 |
| Grant date | Aug 16, 1994 |
| Priority date | — |
| Expiry date | Jun 22, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/6432
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An n-type silicon (Si) wafer is galvanostatically etched in a hydrofluoric acid (HF)-containing solution while being illuminated with a 300 watt tungsten light source to form porous silicon with luminescent properties. Photoluminescence of the porous silicon is monitored using a short wavelength visible or ultraviolet light source and a monochromator/CCD detector assembly. Upon exposure to organic solvents, the photoluminescence is quenched. Within seconds of removal of the solvent, the original intensity is recovered and further exposure of the porous silicon to organic solvents will again result in quenching of the luminescence.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.