Fabrication and Properties of Indium Tin Oxide/ZnO Schottky Photodiode with Hydrogen Peroxide Treatment

A transparent, efficient ZnO ultraviolet Schottky detector with indium tin oxide (ITO) as a metallic contact layer is fabricated on ITO-coated glass substrates by cw CO2 laser evaporation. The device behavior changes from near ohmic to Schottky in the current-voltage characteristics after hydrogen peroxide treatment on the ZnO surface with a fitted barrier height of 1.16 eV, an ideality factor of 2.31, and a leakage current of 3: 1 x 10(-7) A at -3 V bias. Photoluminescence (PL) data show the effect of hydrogen peroxide, and indicate that the surface defects are removed, and better diode characteristics are shown. (C) 2011 The Japan Society of Applied Physics