Electromagnetically carrier depleted IR photodetector

摘要

Abstract: A method is presented for the thermal noise reduction in a near room-temperature intrinsic IR photodetector. The method is based on suppression of the Auger generation-recombination processes using the Electro-Magnetic Carrier Depletion (EMCD) of a narrow gap semiconductor. The device is a lightly doped narrow gap semiconductor flake with a high backside surface recombination velocity, supplied with electrical contact and placed in a magnetic field. Due to action of the Lorentz force, most of the device depletes in charge carriers, resulting in suppression of the Auger generation and recombination processes. As a result, the I-V characteristic becomes nonlinear, exhibiting regions of high positive and negative resistance. The thermal noise can be dramatically reduced, leading to a substantial improvement of performance. The ultimate detectivity may be determined either by the background radiation or by the Shockley-Read generation, in dependence on the ratio of the background photon flux to the recombination center concentration. The near-BLIP performance is predicted for 10.6 $mu@m (Hg,Cd)Te devices, prepared from high quality materials and operated at 225 - 250 K.!