Interface state mapping in a Schottky barrier of the organic semiconductor terrylene

In this work we quantitatively map interface states in energy in a Schottky barrier between aluminum and the vacuum sublimed organic semiconductor terrylene. The density map of these interface states was extracted from the admittance spectroscopy data. They revealed an interface state density of ?2×1012 cm-2 eV-1 close to the valence band which decreases slightly towards midgap. Additional dc measurements show that the semiconductor bulk activation energy is 0.33 eV which may correspond to an acceptor level.