Photovoltaic Action in Polyaniline/n-GaN Schottky Diodes

Schottky diodes were fabricated on n-GaN films by coating them with an organic polyaniline layer as transparent conducting electrodes. These diodes have a high Schottky barrier height (1.28 eV) and a low reverse leakage current (2.7 x 10(-9) A/cm(2) at an applied bias of -1 V). The photovoltaic action of these diodes (V-OC = 0.67 V and external quantum efficiency similar to 30%) was studied under the illumination of an Air Mass 1.5 solar simulator. The polyaniline/n-GaN Schottky contacts were found to be sensitive to shorter wavelengths, indicating their potential for use as solar cells. (C) 2009 The Japan Society of Applied Physics