Plural-wavelength infrared detector devices
US5185648A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1991 |
| Grant date | Feb 9, 1993 |
| Priority date | — |
| Expiry date | Sep 10, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/193
Abstract
An infrared detector device for at least two wavelengths, i.e. 3 to 5 microns and 8 to 14 microns, comprises detector elements (10 and 20) formed in two or more infrared-sensitive materials with different badgaps, e.g. in cadmium mercury telluride. These materials may be provided side-by-side in a single level on a substrate (3) or preferably as different levels (1 and 2) on the substrate (3). Each detector element (10 and 20) comprises a p-n junction (11 and 21) between opposite conductivity type regions (12,13 and 22,23). Electrical connections (15,25,24) extend from these regions to the substrate (3). Freedom in design and fabrication is obtained by a connection structure in which one connection (25) of the longer-wavelength response element (20) contacts both the semiconductor material (2) of that element (20) and the larger-bandgap material (1) of the shorter-wavelength response element (10), at a side-wall (42) of both materials. The larger-bandgap material (1) comprises a further region (18) which adjoins the side-wall (42) and which forms a further p-n junction (19) electrically in parallel with the p-n junction (21) of the longer-wavelength detector element (20).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.