Low resistance ohmic contacts are essential to improve the performance of pentacene-based electronic and optoelectronic devices In this study we reported ohmic contact formation at the indium tin oxide (ITO)/pentacene and indium cerium oxide (ICO)/pentacene interfaces According to the observed results from current-voltage and Kelvin probe measurements we found that the lower contact resistivity of the ICO/pentacene sample than the ITO/pentacene sample may be attributed to the higher surface work function of ICO than ITO (C) 2010 Elsevier B V All rights reserved