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As spontaneous p-type semiconductors, binary copper oxides (Cu2O, Cu4O3 and CuO), have attracted much attention for their great potential applications in information display and energy conversion.This work aims to investigate the controllable growth of copper oxide thin films and their electrical and optical properties.Copper oxide thin films have been deposited on glass substrates at room temperature by reactive magnetron sputtering.As a function of the oxygen flow rate and the total pressure, 3 main deposition zones corresponding to the 3 oxides have been evidenced by X-ray diffraction and Raman spectrometry.At the border of these 3 zones,biphased domains (Cu2O + Cu4O3 or Cu4O3 + CuO) have been systematically evidenced by Raman and TEM.Total sputtering pressure can be used to tune the preferred growth orientation of single phase thin films.For example, <100> texture is formed at low total pressure and high total pressure prefers to produce the <111>textured Cu2O film.What is more, the growth orientation of Cu2O thin films can also be controlled via the homoepitaxial growth using a two-step deposition procedure.Oxygen flow rate plays the predominant role to tune the electrical properties: the room temperature resistivity of these 3 oxides with pure phase decreases with increasing oxygen flow rate.The room temperature resistivity of CuO thin films can be reduced by 3 orders via increasing oxygen flow rate.Referring to the calculating defect mechanism, the electrical properties have been discussed.The biphased film has a lower resistivity than the single phase, which has been discussed based on the unusual mierostructure.Post annealing treatments in air at various temperatures have been performed to improve the properties of Cu2O.Low temperature annealing (< 300 ℃) avoids the film oxidation into CuO and the films remain single-phased.In this temperature range, the annealing in air enhances the transmittance in the visible region due to the decrease of the defect scattering.Moreover the optical band gap of Cu2O thin films is enlarged with increasing annealing temperature.The increase of optical band gap accompanying the reduction of Urbach energy indicates that the widening of optical band gap may result from the partial elimination of defect band tail after thermal annealing in air.The valence-band spectra measured by UPS confirm the existence of defect band tail.Combining valence electron energy loss spectroscopy and UV-Vis spectrometer together, an indirect band gap of 1.3 eV has been determined in Cu4O3.Finally, the electronic structures of Cu2O, Cu4O3 and CuO, investigated by XPS, UPS and EELS, have been discussed.