THE LIGHT INDUCED CHANGE IN TRANSIENT PHOTOCONDUC-TIVITY OF POLYMORPHOUS SILICON FILMS

The decays of transient photoconductivity and their light-induced changes of polymorphous silicon (pm-Si:H) films were investigated. The decays can be fit fairly well by a sum of two exponential decay functions, which indicates that there are two kinds of traps contributing to the process. The light-induced changes of the concentration and energy level of the traps were estimated. The results show that the light-induced changes in trap energy position Et, trap concentration Nt as well as photoconductivity are markedly less for pm-Si:H than that for a-Si:H.