Apparatus for determining the density of unoccupied electronic states of a material
US4472634A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 1982 |
| Grant date | Sep 18, 1984 |
| Priority date | — |
| Expiry date | Apr 29, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2223/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention relates to an apparatus for determining the electron states of a material. This apparatus comprises an enclosure containing a material, means for producing electrons of energy E.sub.i such, that on then penetrating the material, they acquire an energy E.sub.f below E.sub.i, accompanied by an emission of photons having different wavelengths. The apparatus also comprises another enclosure equipped with a tube entering the vacuum enclosure and provided with an entrance slit and another tube provided with a regulatable exit slit. The apparatus also comprises a grating located in the other enclosure and etched with lines, whilst being able to rotate about an axis parallel to these lines in order to select photons of the same wavelength. The apparatus finally has means for detecting the selected photons. Application to the determination of the forbidden band of a semiconductor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.