PHOTOELECTRIC PROPERTIES OF PB1-X-YSNXGEYTE - IN EPITAXIAL-FILMS

Pb1-x-ySnxGeyTe:ln epitaxial films are examined in a wide temperature interval and at various background fluxes. These films have high sensi tivity to infrared radiation in the spectral range lambda < 20 mum. Th e lifetime depends exponentially on temperature and varies from severa l seconds at T = 10 K to 10(-2) s at T = 20 K. The two-electron model of Jahn-Teller centers is proposed to explain the results. Multielemen t photoresistors based on these films are fabricated and D = 1.7 x 10 (13) cm Hz1/2 W-1 at T = 25 K is achieved. Noise of the photoresistors is independent of background flux when it varies from 10(12) CM-2 s-1 to 10(18) CM-2 s-1. As compared with Si:Ga and Ge:Hg photoresistors, the responsitivity is several orders larger at the operating temperatu re 25-30K.