We synthesized diethylamido tantalum (EtN = Ta(NEt2)(3) + Ta(NEt2)(4)) and diethylamido hafnium (Hf(NEt2)(4)). Using nearly identical methods, as precursors for Ta- and Hf-compound films. Both precursors were liquid Lit room temperature and had vapor pressure (Ta: 6Torr at 60degreesC, Hf: 7.5Torr at 80degreesC) moderate enough for chemical vapor deposition (CVD). We deposited TaN thin films from diethylamido Ta and HfO2, thin films from Hr(NEt2)(4)/O-2 using metal-organic CVD. The TaN films were amorphous and the HfO2 films were polycrystalline. Both types had good quality step coverage. (C) 2002 Elsevier Science B.V. All rights reserved.