The electrical behaviour of Al/Al2O3/p-Ge MOS capacitors, with 10 nm oxide thickness, has been studied in the temperature range between 130 K and 330 K. The ALD method for the Al2O3 deposition has been used. C-V and G-f measurements reveal high values of the density of interfacial traps Dit, suggesting the presence of leakage currents. Conductivity mechanisms for the leakage currents have been studied, on the basis of J-V characteristics of the structure as a function of temperature. In the measured voltage region (0-2.5 V), tunneling is proposed as the dominant mechanism. Specifically, as the applied field increases, Fowler-Nordheim mechanism gradually contributes to the, observed at low fields, Ohmic conduction (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]