Lack of temperature dependence of Fermi level pinning at the Cu/InP(110) interface: A comparison with Cu/GaAs and other systems

Cu/GaAs(110) and Cu/InP(110) interfaces prepared at room temperature and 80 K low temperature have been studied using photoelectron spectroscopy. The temperature effect on the interface reactivity and the Fermi level pinning is quite different at these two interfaces despite the fact that the Cu overlayer morphology changes in the same way. For Cu/GaAs, the interfacial chemical reaction is suppressed at low temperature and the Fermi level pinning pattern varies significantly. In contrast, little change in the reaction for InP at low temperature, and consequently lack of temperature dependence of the Fermi level pinning is observed. The results provide insight into the Schottky barrier formation.