Photo-electric properties of ultra-thin cuprous oxide films prepared by electrodeposition

Electrodeposition of cuprous oxide thin film is becoming a more and more important method, but higher content of Cu²⁺ and uneven grain size in cuprous oxide thin films fabricated by direct current (DC) electrodeposition lead to serious reduction of transmission and electron transport capacity of the films. To solve these problems, bidirectional pulse electrodeposition (BPD) was applied in this paper to prepare cuprous oxide thin films and the variety on the photo-electrical properties has been presented. The results indicated that grain uniformity of films fabricated by BPD was improved significantly, the grain size distribution range reduced from 5–50 nm to 10–30 nm, the roughness of the films decreased from 5.83 to 5.26 nm, and the proportion of Cu⁺ in the resulted films increased from 59.21 to 69.61%. The transmittance of films at 550 nm increased from 65.21 to 70.17%, and the surface resistances of the resulted films decreased from 15.7–18.1 to 10.9–11.7 Ω. This method provided a basis for the production of higher-purity and higher-performance thin Cu₂O films.