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

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 approximate to 1.3 x 10(13) cm(-3). At higher temperatures the diffusion mechanism takes over, with I similar to exp(-qV/nkT) and n = 10-20. Relaxation processes for the reverse current and photocurrent (ascending branch) have a delayed character (up to t similar or equal to 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. (C) 1998 American Institute of Physics. [S1063-7826(98)01209-5].