Title page for etd-0707115-211134


[Back to Results | New Search]

URN etd-0707115-211134
Author Ying-Chieh Wang
Author's Email Address No Public.
Statistics This thesis had been viewed 5350 times. Download 0 times.
Department Physics
Year 2014
Semester 2
Degree Ph.D.
Type of Document
Language English
Title Study of GaN and its alloys for spintronics and optoelectronics
Date of Defense 2015-07-19
Page Count 113
Keyword
  • MBE
  • GaN microdisk
  • spin-splitting
  • nano-device
  • AlGaN/GaN heterostructure
  • GaN
  • Abstract The potential of wurtzite GaN and it alloys for applying in the spintronics and optoelectronics has been discussed in this dissertation. For the application of spintronics, AlxG1-xN/GaN samples with different x value have been prepared for the study of the k-dependent spin-splitting in AlxG1-xN/GaN heterostructure by shubnikov-de Haas measurement. A larger spin splitting energy is obtained by pushing the Fermi level in the quantum wells toward the anti-crossing point of ΔC1 and ΔC3 bands. We also demonstrated the spin-orbit interaction by the interference of Rashba, Dresselhaus effects and high-field Zeeman effect in wurtzite GaN/AlxG1-xN heterostructures from SdH measurements, which is yielding an anomalous k-dependent spin splitting energy. Besides, with the nonlinear least-square curve fitting technique, the type I non-parabolic effective mass has been evaluated from the temperature Shubnikov-de Haas measurements.
    For the application of optoelectronics, GaN grown on γ-LiAlO2 substrate by plasma-assisted molecular beam epitaxy has been investigated. The optimized growth condition for M-plane epi-film and self-assembled c-plane microdisks has been discussed. In addition, the GaN microdisk has been lifted out for the application of nanostructure LED. The nanoscale ohmic contact has been fabricated on a single GaN microdisk. The resistivity for an awl-shaped GaN microdisk has been measured to be 7.037E-3 ohm-cm. Futhermore, we developed a back processing to fabricate an electrical contact of GaN microdisk on transparent p-type GaN template which can resolve the obstacle of electrical contacts for self-assembled wurtzite nano-devices.
    Advisory Committee
  • Ming-Chi Chou - chair
  • Meng-En Lee - co-chair
  • Yan-Ten Lu - co-chair
  • K.Y. Hsieh - co-chair
  • Ikai Lo - advisor
  • Files
  • etd-0707115-211134.pdf
  • Indicate in-campus at 5 year and off-campus access at 5 year.
    Date of Submission 2015-08-11

    [Back to Results | New Search]


    Browse | Search All Available ETDs

    If you have more questions or technical problems, please contact eThesys