Current transport in porous p-Si and Pd-porous Si structures

Abstract

Mechanisms are investigated for current transport in porous p-Si and Pd-p-por-Si structures in the temperature range 78–300 K. It is shown that at 78 K drift transport is decisive, with the participation of deep traps with a concentration N _t≈1.3×10¹³ cm⁻³. At higher temperatures the diffusion mechanism takes over, with I∼exp(−qV/nkT) and n=10–20. Relaxation processes for the reverse current and photocurrent (ascending branch) have a delayed character (up to t⋍100 s) and are determined by the effect of traps at a depth E _t=0.80 eV. The temperature behavior of the photocurrent (without a bias) is connected with recombination at a level E _r=0.12 eV, and its value essentially depends on the contribution of the basal region of the diode structure.