Dark currents and reducing defects in image sensors and photovoltaic junctions
US8815634B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 28, 2009 |
| Grant date | Aug 26, 2014 |
| Priority date | — |
| Expiry date | Sep 23, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/50
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Dark currents within a photosensitive device are reduced through improved implantation of a species during its fabrication. Dark currents can be caused by defects in the photo-diode device, caused during the annealing, implanting or other processing steps used during fabrication. By amorphizing the workpiece in the photo-diode region, the number of defects can be reduced thereby reducing this cause of dark current. Dark current is also caused by stress induced by an adjacent STI, where the stress caused by the liner and fill material exacerbate defects in the workpiece. By amorphizing the sidewalls and bottom surface of the trench, defects created during the etching process can be reduced. This reduction in defects also decreases dark current in the photosensitive device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.