VOLTAGE-SWITCHABLE AND-TUNABLE AND ENVIRONMENT-INSENSITIVE MULTI-COLOR SUPERLATTICE INFRARED PHOTODETECTOR

摘要

An infrared photodetector structure with voltage-tunable and -switchable photoresponses constructed of superlattices and blocking barriers. The photoresponses of the double-superlattice structure are also insensitive to the operating temperature changes. By using GaAs/AlxGa1-xAs system, the feasibility of this idea is verified. In the embodiment, the photoresponses can be switched between 6~8.5 and 7.5~12 m by the bias polarity and are also tunable by the bias magnitude in each detection wavelength range. In addition, the photoresponses are insensitive to operating temperatures ranging from 20 to 80 K. For the SLIP with few periods, the responsivity may be higher than the one with many periods and the operational temperature is higher. These results show the invention can be useful in the design of multicolor imaging systems. This invention is not only applicable for wavelengths comparable with the embodiment, but can also be applied to the detection of radiation in the range from visible to extreme far infrared.