Inert ambient annealing effect on MANOS capacitor memory characteristics

In this work we report on the influence of nitrogen ambient thermal effects on the performance of Pt/Al 2 O 3 /Si 3 N 4 /SiO 2 /Si memory capacitors. Two post deposition annealing (PDA) furnace steps were employed, at 850 and 1050 °C both for 15 min. The alumina films were deposited by atomic layer deposition using TMA/H 2 O at 250 °C. The structural characteristics of the stacks were evaluated by transmission electron microscopy and x-ray reflectivity measurements. The memory performance of the stacks was evaluated by write/erase and erase/write measurements, endurance and retention testing. It was found that in as-deposited state the Al 2 O 3 layer is defective resulting in strong leakage currents, controlled by deep defects states. Thus, this behavior inhibits the memory functionality of the stacks. PDA crystallizes and condenses the Al 2 O 3 transforming the layer from amorphous to pol...

Nikolaos Nikolaou, Panagiotis Dimitrakis, Pascal Normand, Dimitrios Skarlatos, Konstantinos Giannakopoulos, Konstantina Mergia, Vassilios Ioannou-Sougleridis, Kaupo Kukli, Jaakko Niinistö, Kenichiro Mizohata, Mikko Ritala and Markku Leskelä

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