Research of the Photocapacitor Effect in A2B6 Monocrystals

Abstract

This paper is devoted to the research of the photocapacitor effect in A2B6 semiconductor crystals - CdS and CdTe monocrystals with needle structure. Unlike existing thin film monocrystals and bulk materials manufactured from CdS/CdTe, the monocrystals mentioned above have high photoconductivity (Rdark/Rlight = 104 and higher)and low lifetime of charge carriers (less than 1 ms). This feature allowed creating a variable depletion capacitance in the metal-semiconductor contact, its value can be reduced almost to the zero by generating photoelectrons near the contact region. The experimental results of the transmission of rectangular pulses through structures CdS-Indium and CdTe-Indium have been obtained. Irradiation intensity limits has been found, after which the depletion capacitance becomes insignificantly small compared to the diffusion capacity inside the photoconductive crystals.