Photoelectric transducer switchable to a high-resolution or high-sensitivity mode
US5196692A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 1992 |
| Grant date | Mar 23, 1993 |
| Priority date | — |
| Expiry date | Jan 24, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F77/1275
Abstract
A photoelectric transducer having a photocell includes a compound semiconductor substrate in which a photodiode is doped by an impurity of a conductivity type opposite to that of the substrate. An enclosure region is formed by the same doping impurity as the photodiode, surrounding but spaced apart from the photodiode. A gate electrode is formed on a portion of an insulation layer, the latter formed all over the substrate surface, which extends between the photodiode and the enclosure region. The enclosure region is selectively connected, via a contact hole through the insulation layer and a first switch to ground level. The gate electrode is connected via a second switch to a predetermined voltage having the same polarity as the conductivity type of the substrate. In a high-resolution mode, the first switch is closed and the second switch is open, so that the grounded enclosure region prevents carriers generated in the substrate, between the photodiode and the enclosure region, from flowing into an adjacent cell. In a high-sensitivity mode, the first switch is opened and the second switch is closed, so that the gate voltage generates a channel which electrically connects the photo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.