The O-2/N-2 flow ratio during O-3 generation by dielectric barrier discharge has a large impact on the atomic layer deposition (ALD) of metal oxides in a hot wall ALD reactor. For HfO2 ALD using HfCl4 as a metal precursor, a higher growth per cycle and a broader ALD temperature window are obtained when N-2 is added to the O-2 supply of the O-3 generation. A positive impact of N-2 in the O-3 generation is also observed for ZrO2 and La2O3 ALD. A negative impact is observed for Al2O3 ALD: The Al2O3 thickness is reduced for those conditions for O-3 where HfO2 ALD is enhanced. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3355207] All rights reserved.