Determining the interfacial density of states in metal-insulator-semiconductor devices based on poly(3-hexylthiophene)

Low frequency admittance measurements are used to determine the density of interface states in metal-insulator-semiconductor diodes based on the unintentionally doped, p-type semiconductor poly(3-hexylthiophene). After vacuum annealing at 90°C, interface hole trapping states are shown to be distributed in energy with their density decreasing approximately linearly from ∼20×1010to5×1010cm−2eV−1 over an energy range extending from 0.05to0.25eV above the bulk Fermi level.