Characterization of planar pn heterojunction diodes constructed with Cu₂O nanoparticle films and single ZnO nanowires

In this study, we fabricate planar pn heterojunction diodes composed of Cu₂O nanoparticle (NP) films and single ZnO nanowires (NWs) on SiO₂ (300 nm)/Si substrates and investigate their characteristics in the dark and under the illumination of white light and 325 nm wavelength light. The diode at bias voltages of ±1 V shows rectification ratios of 10 (in the dark) and 34 (under the illumination of white light). On the other hand, the diode exposed to the 325 nm wavelength light exhibits Ohmic characteristics which are associated with efficient photocurrent generation in both the Cu ₂O NP film and the single ZnO NW.