Regensburg 2016 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 23: Oxide Semiconductors I
HL 23.5: Vortrag
Dienstag, 8. März 2016, 10:30–10:45, H13
Temperature-dependent anisotropic thermal properties of β-Ga2O3 bulk-crystals — •Martin Handwerg1,2, Rüdiger Mitdank1, Zbigniew Galazka3, and and Saskia F. Fischer1 — 1AG Neue Materialien, Humboldt-Universität zu Berlin, 12489 Berlin, Germany — 2Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 14109 Berlin, Germany — 3Leibniz Institute for Crystal Growth, 12489 Berlin, Germany
Transparent semiconducting oxides like Ga2O3 are important materials for high power electronics and optoelectronics.
Here, we investigate the crystallographic anisotropy of the thermal conductivity and the thermal diffusivity for a β-Ga2O3 single crystal.
The thermal conductivity, thermal diffusivity and specific heat capacity is measured by applying multiple electrical AC-heating methods on Czochralski-grown[1] β-Ga2O3 bulk crystals. At room temperature the thermal conductivity along the [100]-direction in Mg-doped electrical insulating and undoped semiconducting β-Ga2O3 is confirmed as 13± 1 Wm−1K−1[2]. Additionally a value for the [001]-direction of 15± 1 Wm−1K−1[3] is detected.
The observed function λ(T) is in accord with phonon-phonon-Umklapp scattering and the Debye-model for 50 K <T< 300 K. Here a detailed discussion of the phonon-phonon-Umklapp scattering for T< θD is carried out.
[1] Z. Galazka et al. J. Cryst. Growth 404, 184 (2014)
[2] M. Handwerg et al. Semcond. Sci. Technol. 30, 024006 (2015)
[3] M. Handwerg et al. arXiv 1506.05294 (2015)