Hopping Conduction in Structures with Ge Nanoclusters Grown on Oxidized Si (001)

Abstract:

Conductivity and capacitance in structures with Ge nanoclusters grown on oxidized Si (001) with different morphology have been investigated for the temperature range 120-290 K and frequencies 1 kHz-1MHz in co-planar geometry. It was found that structures exhibited T^-1/3 conductivity dependence. The Mott’s variable range hopping through quasi-band of localized states at the Fermi level of Ge nanoclusters and their interfaces was found to be the dominant transport mechanism in the surface conductivity channel. The quasi-band width depends of surface morphology varying in the range 110-130 meV, while the middle of the band is located at E_v+140 meV. The peak of reduced conductivity and capacitance were observed under conditions when Fermi level is in the middle of this band.

• Periodical: Journal of Nano Research (Volume 39)
• Pages: 178-188
• DOI: https://doi.org/10.4028/www.scientific.net/JNanoR.39.178
• Online since: February 2016
• Authors: Vladimir Lysenko, Y.V. Gomeniuk, Valeriya N. Kudina, Nikolay Garbar, Sergey Kondratenko*, Yevgenij Ye. Melnichuk, Yurii N. Kozyrev
• Keywords: Molecular Beam Epitaxy, Quantum Dots, Silicon-Germanium, Transport

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