Temperature-dependent charge transport in copper indium diselenide nanocrystal films

Abstract

This manuscript reports the temperature dependence of majority carrier transport in p-type films of copper indium diselenide (CuInSe2) nanocrystals. Charge transport parameters, such as the carrier concentration and the electrical conductivity as well as the charge transport mechanisms have been characterized through measurements of electrical capacitance and electrical current as a function of applied voltage bias and temperature. At low temperatures, below 181 K, the temperature dependence of the conductivity is consistent with a variable range hopping mechanism for transport, while at higher temperatures, above 181 K, the transport mechanism shifts to nearest neighbor hopping. Charge transport measurements were also studied under AM1.5 illumination to show how energetic barriers for charge transport are reduced under solar cell-like operating conditions.