Nenad Novkovski


Oxygen annealed radio frequency (RF) reactively sputtered and thermally grown (thermal) Ta2O5 films on sili-con were comparatively studied by using combination of C-V and I-V measurements and the previously developed comprehensive model for the metal-Ta2O5/SiO2-Si structures. Dielectric properties of separate layers were extracted by comparing the experimental and the theoretical results. It is found that the net leakage properties of the Ta2O5 layer are significantly better in the case of RF than thermal, particularly in the case of the Au gate. Excessive growth of the SiO2 layer of about 0.3 nm in the case of RF films leads to an unwanted increase of the equivalent oxide thickness. Appropriate interface engineering is required in order to prevent the SiO2 excessive growth during the oxygen anneal-ing. Such a growth can reduce the beneficial effects of the annealing on the net properties of Ta2O5 films obtained by RF.


high permittivity dielectrics; conduction in dielectrics; leakage currents model

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DOI: http://dx.doi.org/10.20903/csnmbs.masa.2018.39.1.116


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