The feasibility of the application of double-gate dielectric stacks with fabricated by atomic layer deposited (ALD) HfO2 and Al2O3 layers in non-volatile semiconductor memory (NVSM) devices was investigated. Significant improvement in retention at elevated temperatures after the application of ALD high-k oxides was demonstrated. Superior memory window (extrapolated at 10 years) of flat-band voltage (U-fb) value of the order of 2.6 V and 4.55 V at 85 degrees C, for stack with HfO2 and Al2O3, respectively, was obtained. Moreover, the analysis of conduction mechanisms in the investigated stacks under negative voltage revealed F-N tunneling in the range of high values of electric field intensity and lowering of barrier height with increasing temperature. (c) 2012 Elsevier B.V. All rights reserved.