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United States Patent | 5,206,526 |
Liu ,   et al. | April 27, 1993 |
Disclosed are novel fast semiconductor photodetector means that comprise a good asymmetric superlattice structure. Associated with the material of the structure is a relatively short minority carrier effective lifetime .tau..sub.e, typically .tau..sub.e <10.sup.-9 sec. In response to a constant photon flux of appropriate wavelength the photodetector can have a substantially constant voltage output that is proportional to the photon flux for small values of flux, and that saturates at a value that is substantially proportional to .tau..sub.e.sup.-1 for relatively large values of flux. The novel photodetector means can be advantageously combined with a FET or bipolar transistor, and the combination can be part of an integrated circuit.
Inventors: | Liu; Chun-Ting (Piscataway, NJ); Luryi; Sergey (Bridgewater, NJ) |
Assignee: | AT&T Bell Laboratories (Murray Hill, NJ) |
Appl. No.: | 699057 |
Filed: | May 13, 1991 |
Current U.S. Class: | 257/185; 257/21; 257/290; 257/432 |
Intern'l Class: | H01L 031/030.4 |
Field of Search: | 357/16,4,30 |
4694318 | Sep., 1987 | Capasso et al. | 357/16. |
4974044 | Nov., 1990 | Cunningham et al. | 357/16. |
5051804 | Sep., 1991 | Morse et al. | 357/16. |
5075743 | Dec., 1991 | Behfar-Rad | 357/16. |
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