We fabricated a normally-off mode n-channel schottky barrier metal oxide semiconductor field effect transistor (SB-MOSFET) with transparent electrodes (ITO, IZO) as source/drain (S/D) contact on a highly resistive GaN layer grown on silicon substrate. Fabricated SB-MOSFET with ITO S/D exhibited as high as 40 mA/mm of maximum drain current and a 12 mS/mm of maximum transconductance with the threshold voltage of 4.2 V. which is far better than that of SB-MOSFET with IZO S/D. The normalized off-current was as low as 10 nA/mm. The UV-visible extinction ratio of a MOSFET type UV-sensor was measured over 130 for V-DS = 5 V. ITO was proved as a promising schottky barrier material for GaN MOS-FET source and drain not only for the electronic but UV-sensing applications better than IZO for this purpose. (C) 2012 Elsevier Ltd. All rights reserved.