Regensburg 2010 – wissenschaftliches Programm
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HL: Fachverband Halbleiterphysik
HL 31: Poster I: Devices, Quantum Dots and Quantum Wires
HL 31.43: Poster
Dienstag, 23. März 2010, 18:30–20:30, Poster D1
Temperature Dependent Photoluminescence of Wet Chemically Etched Silicon Nanowires — •Viktor Gerliz1, Vladimir Sivakov2, Silke Christiansen2, Felix Voigt1,2, and Gottfried H. Bauer1 — 1University of Oldenburg, Institute of Physics, Carl-von-Ossietzky-Str.9-11, D-26129 Oldenburg, Germany — 2Institute of Photonic Technology, Albert Einstein Str.9, D-07745 Jena, Germany
Silicon nanowire (Si-NW) samples were prepared by Wet Chemical Etching of crystalline silicon wafers. The diameters of these Si-NWs ranged from 30 to 200 nm. Photoluminescence (PL) measurements were performed with excitation at 458 nm and a laser power of 3.2 mW with 1.1 mm beam diameter. According to the Si-NW diameter size > 10 nm, from quantum confinement theory no shift in PL peak energy compared to crystalline silicon is expected. However, PL measurements show peak emission energies in the range 1.4 to 1.6 eV. After further treatment of the samples with HF, substantial PL emission was still detectable and the measured PL peak was pinned at 1.4 eV, irrespective of etching time. For samples treated such way the high energy wing of the steady state PL spectra show a linear behavior in the log-PL vs. photon energy plot pretending - according to Planck′s generalized law - a temperature of 103 K. By temperature PL-experiments we are able to discriminate between the influence of temperature on the slope of the high energy Pl wing and a distribution of sites with individual, say, non-overlapping wave functions which also leads to exponentially decaying PL emission.