Photocathode having AlGaN layer with specified Mg content concentration
US6831341B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 2003 |
| Grant date | Dec 14, 2004 |
| Priority date | — |
| Expiry date | May 14, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2231/50021
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Ultraviolet light incident from the side of a surface layer 5 passes through the surface layer 5 to reach an optical absorption layer 4. Light which reaches the optical absorption layer 4 is absorbed within the optical absorption layer 4, and photoelectrons are generated within the optical absorption layer 4. Photoelectrons diffuse within the optical absorption layer 4, and reach the interface between the optical absorption layer 4 and the surface layer 5. Because the energy band is curved in the vicinity of the interface between the optical absorption layer 4 and surface layer 5, the energy of the photoelectrons is larger than the electron affinity in the surface layer 5, and so photoelectrons are easily ejected to the outside. Here, the optical absorption layer 4 is formed from an Al0.3Ga0.7N layer with an Mg content concentration of not less than 2×1019 cm−3 but not more than 1×1020 cm−3, so that a solar-blind type semiconductor photocathode 1 with high quantum efficiency is obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.