Control of carrier concentration in thin cuprous oxide Cu2o films by atomic hydrogen

A stable cuprous oxide Cu2O film is prepared by low-temperature oxidation of a sputtered copper (Cu) thin film at 300°C. Although the carrier concentration in Cu2O is determined by the excessive oxygen (O) concentration, the concentration of such O atoms is controlled by the exposure to atomic hydrogen (H) generated by the catalytic reaction between the heated tungsten catalyst and H2 gas. By this method, the carrier concentration in a 100-nm-thick Cu2O film is decreased from 1 × 1016 cm-3 3 to 2 × 1015 cm-3 and the Hall effect mobility is increased from 5.6 cm2/Vs to 28.9 cm2/Vs. Atomic H exposure is a useful tool for improving the properties of Cu2O.