The interface state densities of Cu/CuO/n-Si Schottky structure were investigated by current-voltage (I-V) and capacitance-voltage (C-V) measurements using Roderick and Card's methods in the temperature range 50-310 K. The interface state density (NSS) as a function of energy distribution (EC-ESS) was extracted from the forward-bias I-V measurements by taking into account the bias dependence of the effective barrier height and series resistance. Furthermore, the values of NSS obtained as a function of temperature. The experimental results have shown that the interface state densities (NSS) value of Cu/ CuO/n-Si Schottky structure decreases with increasing EC-ESS values as a function of temperature. Such behavior of interface state densities (NSS) has been explained with variation of the ideality factor as a function of temperature due to lateral inhomogeneities of the barrier height at the metal-semiconductor interface. (c) 2021 Elsevier Ltd. Selection and peer-review under responsibility of the scientific committee of the International Congress on Semiconductor Materials and Devices, ICSMD2018.