Transient photovoltaic investigations of a Schottky-type porous silicon diode

We report the transient photovoltaic characters of a Schottky-type porous silicon diode excited by 10 ns laser pulses at 532 nm. At room temperature, the transient photovoltage profile consisted of two different decay components. The fast one had a characteristic decay time of 44 ns and the dominant slow process one of . They were attributed to carrier recombinations in porous silicon involving surface states and phonon-assistance respectively. At 77 K, the fast process dominated and the slow one was missing. The photovoltage increased exponentially with increasing excitation intensity and reached saturation at .