The thermal quenching and supralinearity of photoconductivity in hydrogenated amorphous silicon

Abstract

The temperature and illumination intensity dependences of photoconductivity (PC) due to the presence of different types of recombination centres in undoped a‒Si: H are investigated in terms of the Rose-Simmons-Taylor theory. The results show pronounced structure in the temperature dependence curves of PC. In the temperature range where this structure appears, slight supralinearity can be observed. Due to the competition between recombination centres and the electron sensitizers, the PC can be either increased or decreased by more than an order of magnitude; also the features of the PC temperature dependence are different. These are compared with the annealed state or light-soaked state of undoped a‒Si: H.