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1	Optical properties of GaMnN films grown by PA-MBE Chiang, Wei-Yang 09 August 2011 (has links) We have grown Ga1-xMnxN films on c-sapphire substrate by plasma-assisted MBE with different Mn fluxes. The films are characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), electron backscatter diffraction (EBSD), high¡Vresolution X-ray diffraction (HR-XRD), Raman scattering, photoluminescence (PL), cathodoluminescence (CL), transmission spectra, reflection spectra and X-ray photoelectron spectroscopy (XPS). The SEM images show films thickness between 550 to 850 nm and EBSD indicates samples normal direction is c-axis. EDS spectra show the Mn is present in GaMnN samples. According to XRD and Raman scattering, Mn element occupying Ga site on GaN and Mn-N clusters phase coexist on films. From transmission and reflection spectra, stronger absorption at about 1.5 eV and 1.8 eV to 3.4 eV absorption band are found. The PL and CL show GaN band gap at 3.4 eV and blue band from 2.4 eV to 3.3 eV maybe due to defect level. Finally, the XPS spectra indicate Mn acceptor level is contributed to Mn+2 or Mn+3 states. GaMnN Absorption Raman Diluted Magnetic Semiconductor Luminescence
2	Characterization and Growth of GaMnN Nanorods Grown by Plasma-Assisted Molecular Beam Epitaxy Chen, Ting-Hong 31 July 2012 (has links) In this work, Mn atoms are doped into GaN nanorods by two doping types, homogeneous and delta doping, and GaN nanorods are grown on Si (111) substrate using plasma-assisted MBE. The GaMnN nanorods are characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), high-resolution x-ray diffraction (HR-XRD), Raman scattering, Transmission electron microscopy (TEM), superconducting quantum interference device (SQUID), and x-ray photoelectron spectroscopy (XPS). The Mn delta-doping GaN nanorods with Ga/Mn growth time ratio 20 are approximately 1500 nm in height, grown along the c-axis. The Mn concentration in nanorods is determined to be 0.83% by EDS, without secondary phase formation. The Mn atoms substitute Ga sites in the GaN wurtzite hexagonal structure and, according to the results of Raman, there is no observable Mn-N cluster formation existed. The delta-doping structure, without secondary phase inclusions, can be observed under TEM imaging of the nanorods. The nanorods appear to show ferromagnetic behavior at room temperature, as judged by the M-H with hysteresis curve, however the small the loops are. The delta-doping is adopted in this thesis work to fabricate GaMnN DMS nanorods without secondary phase formation. MBE GaN Nanocolumn DMS Nanorod GaMnN
3	Nanostructures And Thin Films Of III-V Nitride Semiconductors Sardar, Kripasindhu 10 1900 (has links) (PDF) No description available. Semiconductors Thin Films Nanostructures Nitrides Nitride Semiconductors Nanowires Nanocrystals Semiconductor Nanostructures AlN GaN InN Gallium Nitride Nanotubes Nitnde Thin Films GaMnN Films Nanotechnology
4	Optische Eigenschaften von verdünnten magnetischen Halbleitern auf GaN-Basis / Optical properties of GaN-based diluted magnetic semiconductors Zenneck, Jan 18 July 2007 (has links) No description available. 530 Physik Mathematics and Computer Science GaN GaMnN GaGdN GaCrN DMS PL Raman XRD Magneto-Optik MBE intra-3d GaN GaMnN GaGdN GaCrN DMS PL Raman XRD magneto-optics MBE intra-3d 33.72 RVQ 460: Elektrische
5	Ferromagnetismus bei Raumtemperatur in mehrphasigen (Ga,Mn)N Schichten und Heterostrukturen / Ferromagnetism at room temperature in multiphase (Ga,Mn)N layers and heterostructures Mai, Dong-Du 15 July 2009 (has links) No description available. 530 Physik Mathematics and Computer Science GaN (Ga Mn)N GaMnN DMS MBE SQUID TEM XRD PL Ferromagnetismus Superparamagnetismus Spin-Glas GaN (Ga Mn)N GaMnN DMS MBE SQUID TEM XRD PL ferromagnetism superparamagnetism spin-glass 33.05 33.09 33.6 33.68 33.72 33.75 RVQ 460: Elektrische 800

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