Barrier properties of TiAlxNyOz films between electron-beam evaporated Cu thin films and thermally grown SiO2 substrates are investigated by Rutherford backscattering spectrometry, X-ray diffractometry (XRD), electrical resistivity measurement and adhesion tests. The Cu/TiAlxNyOz/SiO2/Si samples are analyzed prior to and after vacuum anneals up to 800 degreesC for 1 h. Backscattering analysis indicates that the TiAlxNyOz thin films are formed by reactive sputtering technique using the TiAl alloy target, nitrogen flow and high substrate temperature (400 degreesC). Furthermore, Cu diffusion through TiAlxNyOz films does not occur even at high temperature (800 degreesC). XRD and electrical resistivity measurements show good thermal stability of Cu thin films annealed in vacuum at temperatures varying from 400 to 800 degreesC for 1 h. In addition, it is revealed by tape test that Cu thin films adhere to TiAlxNyOz films very well. Results show that Cu thin film on TiAlxNyOz can be used in the application of high temperature electronics due to its excellent high temperature properties. (C) 2003 Elsevier B.V. All rights reserved.