Electrical properties of Ta2O5 thin films deposited on Cu

Abstract

The electrical and dielectric properties of reactively sputtered Ta2O5 thin films with Cu as the top and bottom electrodes forming a simple metal insulator metal (MIM) structure, Cu/Ta2O5/Cu/n-Si, were studied. Ta2O5 films subjected to rapid thermal annealing (RTA) at 800 degrees C for 30 s in N-2 ambient crystallized the film, decreased the leakage current density and resulted in reliable time-dependent dielectric breakdown characteristics. The conduction mechanism at low electric fields (<100 kV/cm) is due to Ohmic conduction; however, the Schottky mechanism becomes predominant at high fields (>100 kV/cm). Present studies demonstrate the use of Cu as a potential electrode material to replace the conventional precious metal electrodes for Ta2O5 storage capacitors. (C) 2000 Elsevier Science S.A. All rights reserved.