Communication-Improving Optoelectronic Properties of Electrochemically Deposited Cuprous Oxide Thin-Films by Low-Temperature Post-Deposition Annealing

The effect of low-temperature post-deposition annealing (PDA) on electrochemically deposited cuprous oxide (ECD-Cu2O) thin-films was investigated. The PDA at 150°C drastically improved optoelectronic properties of ECD-Cu2O films regardless of annealing atmosphere. The films exhibits free exciton luminescence at room temperature and a high hole mobility about 18 cm2/V·s. Moreover, the diffusion length of photo-generated carriers increased around two times compared to the as-deposited film. On the other hands, the PDA at 200°C significantly deteriorated the optoelectronic properties presumably due to the increase of mid-gap defects in the Cu2O films.