SiO2 films were successfully deposited onto n-GaAs substrates by photo-chemical vapor deposition (photo-CVD) using a deuterium (D-2) lamp as the excitation source. With a 1 MV/cm applied electric field, it was found that the SiO2 films leakage current densities were 1.74 x 10(-6) and 1.97 x 10(-7) A/cm(2), respectively, for the capacitors with as-deposited and 400 degrees C annealed insulator layers. The interface state densities, D-it, were also found to be small for the fabricated Al/photo-CVD-SiO2/GaAs metal-oxide-semi-conductor field effect transistors (MOSFETs) capacitors. (c) 2005 Elsevier Ltd. All rights reserved.