Current–voltage characteristics of a tetracene crystal:Space charge or injection limited conductivity?

Abstract

We show that current–voltage characteristics, measured on a tetracene crystal sandwiched between two gold electrodes, are in quantitative agreement with the concept of dopant-assisted charge injection across a metal–organic interface. This notion explains the wild range of carrier mobilities recently found by space-charge limited current measurements in apparently identical tetracene crystals [de Boer et al., J. Appl. Phys. 95, 1196 (2004)] and the difference between these data and the mobility measured in the time-of-flight experiments.