Method for the determination of the capture cross sections of electrons from space-charge-limited conduction in the dark and under illumination in amorphous semiconductors

The current transport equations describing space-charge-limited conduction in the dark and under illumination in amorphous' materials have been studied. With a certain number of reasonable approximations, a very simple relation in the form Y=sv X is obtained where Y and X are two quantities directly linked to the values of dark currents and photocurrents measured at two different voltages and sv is the product of capture cross section of states near the Fermi level and thermal velocity of carriers. The model is then applied to n(+)-i-n(+) hydrogenated amorphous and polymorphous structures. (C) 2004 American Institute of Physics.