The performance degradation of the thin-film electrodes has remained a challenge for the whole performance of micro-devices. Here, we introduce substrate bias voltage (SBV) in magnetron sputtering technique to improve the thermal stability and reliability of copper (Cu) electrode. The effects of the SBV on the stability and reliability of Cu film electrodes were investigated by scanning electron microscopy and thermal shock. Unstable electric performance is suppressed, and the interface bonding strength between the film and substrate is obviously improved by applying SBV. In addition, this work provides a facile way to achieve high reliability and thermal stability for Cu electrodes used in various thin-film devices. (C) 2016 Elsevier B.V. All rights reserved.