Method of measuring photo-induced voltage at the surface of semiconductor materials
US4544887A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 21, 1982 |
| Grant date | Oct 1, 1985 |
| Priority date | — |
| Expiry date | Oct 21, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/2831
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of determining the photo-induced voltage at the surface of a specimen of semiconductor material. A beam of monochromatic light of low intensity and of wavelength shorter than that corresponding to the energy gap of the semiconductor material is directed at the specimen. The light beam is modulated, and the resulting AC photovoltage signal induced at the surface of the specimen is measured. Measurements of surface photovoltage made in this way can be used to determine the surface space-charge capacitance of the specimen of semiconductor material and, therefore, to characterize the properties of the semiconductor material using conventional capacitance analysis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.