TEMPERATURE-DEPENDENCE OF RADIATIVE AND NONRADIATIVE-TRANSITIONS IN POROUS SILICON

Spectral position, intensity and decay of photoluminescence (PL) were investigated in porous silicon between temperatures of 30 K and 300 K. The maximum of the PL band has a blue shift when the temperature is d ecreased. For the photoluminescence observed within 1-10 mu s from the moment of excitation this shift is linear in T over the temperature r ange investigated. Instead, the luminescence observed after 30-100 mu s has a complex temperature dependence above 150 K. This effect is att ributed to the influence of non-radiative transitions to the populatio ns of the states involved.