Properties of high-mobility Cu2O films prepared by thermal oxidation of Cu at low temperatures

Cuprous oxide (Cu2O) films are prepared by simple thermal dry oxidation of sputtered Cu films at temperatures lower than 350 degrees C. The relationship between growth rate of Cu2O film and oxidation temperature is formulated from both optical and Rutherford backscattering measurements, along with a similar relationship for the growth of cupric oxide (CuO). Electrical and structural properties of Cu2O films are measured by the van der Pauw and the X-ray diffraction methods respectively. It is found that stable Cu2O films can be obtained under suppression of CuO growth when Cu films are oxidized at about 300 degrees C, and that the Hall mobility of such Cu2O films is relatively high and reaches to several tens cm(2)/Vs.