Dresden 2009 – scientific programme

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DF: Fachverband Dielektrische Festkörper

DF 13: Thin Films and Nanostructures I

DF 13.2: Talk

Wednesday, March 25, 2009, 15:00–15:20, WIL B321

The influence of charged traps on leakage current through thin dielectric films — •Grzegorz Kozlowski, Jaroslaw Dabrowski, Piotr Dudek, Gunther Lippert, Grzegorz Lupina, and Hans-Joachim Müssig — IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany

We consider a problem of tunneling effect through a dielectric film with a certain distribution of charged traps inside. The transmission coefficient is calculated directly from the one dimensional stationary Schrödinger equation. Correction compensating the charge inhomogeneity in the film (charged defect) as well as the effect of image potential on a tunnelling carrier was included in the calculation. Since trap position in film determines the life time of carriers on a resonant state in defect, for traps in the bulk of the material a typical resonant tunneling takes place. On the other hand, as trap is moved towards the electrode (anode), the influence of resonant state on leakage becomes weaker. For defects in vicinity of anode, the effect of lowering the potential barrier due to the presence of charged defect is dominating and we observe the effective shortening of tunneling path. In this case a material can be treated as ideal film with a certain interface roughness. In order to reveal a typical behavior of all investigated mechanisms, additionally a detailed analysis of current in different regimes of applied voltage was performed. The results are compared with experimental data.