Photodiode
US6885075B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 2002 |
| Grant date | Apr 26, 2005 |
| Priority date | — |
| Expiry date | Dec 2, 2022 |
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 λg. One of the absorption layers is sandwiched between the substrate and the light receiving layer, the band gap wavelength λg of the absorption layer is shorter than the receiving signal wavelength λ2 but longer than noise wavelength λ1(λ1<λg<λ2). 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 λ1. The PD has no sensitivity to λ1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.