Solid state devices based on thin films of Cu2O show a new type of I–V relations

Abstract Solid state devices based on Cu 2 O are found to exhibit different current–voltage ( I – V ) relations. Though these devices have been known for almost 80 years they are still not fully understood. The standard interpretation of these I – V relations is by assuming Schottky barriers to exist between a metal electrode and the oxide. We here report on a new form of I – V relations that we have measured for devices based on thin films of Cu 2 O. Their interpretation calls upon mixed ionic electronic conduction in the oxide. The ionic conductivity, though low, is sufficient to allow a redistribution of the native acceptors on the time scale of the measurements, thereby affecting the electronic current carried by holes. Any contribution to the I – V relations from Schottky barriers is not significant.