Performance Enhancement of Inverted Polymer Solar Cells Using Roughened Al-Doped ZnO Nanorod Array

Inverted polymer solar cells with an Al-doped ZnO (AZO) nanorod array were fabricated. Various AZO nanorod arrays were formed using the combination technique of the laser interference photolithography method and the wet etching process. The AZO nanorod array could work as the carrier collection layer and the carrier transportation layer. The short-circuit current density and the external quantum efficiency were improved by the AZO nanorod array. The performance improvements were attributed to the increased probability of charge carrier extraction and charge collection by the AZO nanorod array. A power conversion efficiency of 4.188% for the inverted polymer solar cells with the 100-nm-long AZO nanorod array was obtained. (C) 2012 The Japan Society of Applied Physics