Dresden 2020 – wissenschaftliches Programm
Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 72: Focus Session: Functional Metal Oxides for Novel Applications and Devices III (joint session HL/DS)
HL 72.6: Vortrag
Donnerstag, 19. März 2020, 16:15–16:30, POT 81
Low-frequency noise characterization of MOCVD-grown β-Gallium Oxide — •Christian Golz1, Günter Wagner2, Saud Bin Anooz2, Zbigniew Galazka2, Andreas Popp2, Fariba Hatami1, and W. Ted Masselink1 — 1Department of Physics, Humboldt-Universität zu Berlin, Newton-Str. 15, D-12489 Berlin, Germany — 2Leibniz Institute for Crystal Growth, Max-Born-Str. 2, 12489 Berlin, Germany
Low-frequency noise spectroscopy was used to characterize defects and trap states in β-Ga2O3 epilayers. These high-quality Si-doped layers were homoepitaxially grown by metal-organic chemical vapour deposition (MOCVD)[1] on insulating Mg-doped β-Ga2O3 substrates prepared from bulk crystals obtained by the Czochralski method [2].
For noise measurements, lithographically defined Greek cross mesa structures were etched using hot H3PO4. Ohmic Ti/Au contacts were processed by e-beam evaporation. Generation-recombination noise, thermal noise, and 1/f noise are well resolved. Measured Hooge parameter values between 10−5 and 10−3 indicate a high structural quality of the epilayer. Generation-recombination noise was analyzed between 80 K and 400 K, finding up to three deep trap levels. Each of these deep traps is characterized in terms of their density, thermal activation energy, capture cross section prefactor, and binding energy.
[1] R. Schewski et al., APL Mater. 7, 022515 (2019); [2] Z. Galazka et al., ECS J. Solid State Sci. Technol. 6, Q3007 (2017)