Sublinear reverse current-voltage characteristics of thick film structures based on CdTe

Abstract

The film structure with p-CdTe base (w = 120 μm) having from two sides MOS-elements (the frontal Al-n-Al2O3-p-CdTe and the rear Mo-MoO3-p-CdTe) is created. The extended sub linear section (SS) on the current-voltage characteristic is appeared if to turn on such structure in the opposite di rection of the of the current. Mechanism of an appearance of SS is associated with the injection of ele c trons from the rear MOS-element and appearance in the base the diffusion and drift currents what com pensate each other. These physical processes lead to an increasing of the base resistance in the wide range of the biased voltage (Vb ≈ 0.3—70 V) where current (I) remains almost constant (≈6.7·10–7 A/cm2 in the beginning and (≈6.9·10–7 A/cm2 in the end of the range). It is established that in the beginning of SS (Vb ≈ 0.3 V) relaxation processes of transfer are determined by recombination of no equilibrium car riers what were injected into the base and such processes entirely are defined by time of the transit of these carriers through the base.