Photodiode
US6518638B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 9, 2000 |
| Grant date | Feb 11, 2003 |
| Priority date | — |
| Expiry date | May 9, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/3025
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A photodiode (A) comprises a substrate, a light receiving layer having a band gap wavelength and including a pn-junction and at least an absorption layer having a band gap wavelength &lgr;g. One of the absorption layers is sandwiched between the substrate and the light receiving layer, the band gap wavelength &lgr;g of the absorption layer is shorter than the receiving signal wavelength &lgr;2 but longer than noise wavelength &lgr;1(&lgr;1<&lgr;g<&lgr;2). Otherwise a photodiode (B) has two absorption layers epitaxially made on the substrate. One absorption layer is formed on the top surface of the substrate. The other absorption layer is formed on the bottom surface of the substrate. The absorption layers annihilate the noise &lgr;1. The PD has no sensitivity to &lgr;1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.