Optical properties of ZnO nanowire arrays electrodeposited on n- and p-type Si(1 1 1): Effects of thermal annealing

Electrodeposition is a low temperature and low cost growth method of high quality nanostructured active materials for optoelectronic devices. We report the electrochemical preparation of ZnO nanorod/nanowire arrays on n-Si(1 1 1) and p-Si(1 1 1). The effects of thermal annealing and type of substrates on the optical properties of ZnO nanowires electroplated on silicon (1 1 1) substrate are reported. We fabricated ZnO nanowires/p-Si structure that exhibits a strong UV photoluminescence emission and a negligible visible emission. This UV photoluminescence emission proves to be strongly influenced by the thermal annealing at 150–800 °C. Photo-detectors have been fabricated based on the ZnO nanowires/p-Si heterojunction.

► A new template-free electrochemical deposition method for the synthesis of ZnO nanorods/nanowires directly on n- and p-type silicon (Si) substrates.
► Improved structural, electrical and optical properties of the ZnO nanowires/p-Si (1 1 1) heterojunction have been demonstrated.
► Photodetectors have been fabricated based on the n-ZnO nanowires/p-Si heterojunction obtained by electrodeposition.