Berlin 2018 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

DS: Fachverband Dünne Schichten

DS 10: Oxide Semiconductors for Novel Devices (Focussed Session): Session II

DS 10.2: Talk

Monday, March 12, 2018, 15:15–15:30, E 020

The electric field dependence of the permittivity of SrTiO₃ — •Julian Stoever, Laura Bogula, Toni Markut, Jos Boschker, Jutta Schwarzkopf, Martin Albrecht, and Klaus Irmscher — Leibniz Institute for Crystal Growth, Max-Born-Str. 2, 12489 Berlin, Germany

Resistive switching in SrTiO₃ belongs to the interesting applications in the fast growing field of oxide electronics. Oxygen vacancy diffusion due to high electric fields in the depletion layer of SrTiO₃ Schottky diodes is a commonly used model to describe the resistive switching behaviour. The dependence of the permittivity on the electric field strength has been rarely taken into account for SrTiO₃ resistive switching devices. The permittivity of SrTiO₃ is strongly dependent on the temperature and the electric field. Additionally, capacitance-voltage and current-voltage characteristics show deviations of the C^-2-V relation and the thermionic-emission model, respectively. Theoretical models were developed that assume a non-linear dielectric response of the crystal [Reich et al. Phys. Rev. B, 91 11 (2015)]. Another approach is the introduction of a low-permittivity interlayer, as it was done by Yamamoto et al. [Jpn. J. Appl. Phys. 37 4737 (1998)]. To verify the theoretical approaches, fundamental measurements of the permittivity are necessary. We performed permittivity measurements at different temperatures and electric fields on plate capacitor structures made of insulating SrTiO₃. The results will be compared with the behaviour of the Schottky diodes and are important for characterization methods like deep level transient spectroscopy.