Improvement of energy resolution of transient photoconductivity analysis for measuring localized-state distributions in amorphous semiconductors

The energy resolution of the Laplace transformation method for measuring localized-state distributions, based on the analysis of transient photoconductivity (TPC) in amorphous semiconductors, has been improved analytically. The improvement of the energy resolution of the Laplace transformation method is shown for representative localized-state distributions often found in amorphous semiconductors using computer-generated photocurrent transients. The most important finding is that the improved Laplace transformation (LT) method can map a localized-tail-state distribution whose width is smaller than kT.