Electrical conduction in reactively sputtered tantalum oxide thin films

High-field electrical conduction over a temperature range of 303-363 K has been studied in sandwich structures of Al/Ta 2 O 5 /Al and Al/Ta 2 O 5 /Ta in the thickness range 400-900 nm. The oxide film was produced by reactively sputtering a tantalum target in a mixture of argon and oxygen. No marked rectification was observed in the samples and it was observed that the conduction process bore strong resemblance to either a Poole-Frenkel or a Schottky mechanism, the results showing a definite lowering of the activation energy for the conduction process with field. Detailed analysis of the data suggest an electrode-limited mechanism such as that suggested by Schottky.