Sökning: "Gallium Nitride GaN"

Visar resultat 11 - 15 av 16 uppsatser innehållade orden Gallium Nitride GaN.

  1. 11. Scanning probe microscopy with gallium nitride nanowires

    L2-uppsats, Lunds universitet/Fysiska institutionen; Lunds universitet/Fasta tillståndets fysik

    Författare :Victor Ahlinder; [2015]
    Nyckelord :Physics and Astronomy;

    Sammanfattning : In scanning probe microscopy the properties of the tip is crucial in determining which information that can be obtained from the resulting images and spectroscopy. Ordinarily metal tips are used for scanning, however by using semiconducting nanowires as tips one would have very well defined probes with more advanced possibilities for spectroscopic measurements. LÄS MER

  3. 12. Linearity Aspects of Dynamic PA Supply-Modulation Systems with Emphasis on Modulator Modeling and non-linearities

    Master-uppsats, Avdelningen för elektronik, matematik och naturvetenskap

    Författare :Robert Glen Perea Tamayo; [2012]
    Nyckelord :EER; Envelope tracking; hybrid switching amplifiers; power amplifiers supply modulation;

    Sammanfattning : Modern communication systems operate with high peak-to-average-power ratio (PAPR) over wide bandwidth. Linearity requirements force operation in a low efficient highly linear back-off region. Then increasing efficiency is becoming critical. One of the most promising technologies to accomplish this is using supply modulation, e. LÄS MER

  4. 13. Fabrication and Optical Properties of ZnO Nanocrystal/GaN Quantum Well Based Hybrid Structures

    Master-uppsats, Tunnfilmsfysik; Tekniska högskolan

    Författare :Kuo Chieh-Yi; [2012]
    Nyckelord :ZnO; GaN; Hybrid Structure;

    Sammanfattning : Optical properties of hybrid structures based on zinc oxide nanocrystals (NCs) and Gallium Nitride quantum well (QW) has been studied. The ZnO NCs thin films on the top of GaN QW structures were fabricated using spin coating. The surface morphology was characterized by scanning electron microscopy (SEM). LÄS MER

  5. 14. Design and Implementation of as Asymmetric Doherty Power Amplifier at 2.65 GHz in GaN HEMT Technology

    Master-uppsats, Elektroniska komponenter; Tekniska högskolan

    Författare :Mohsin Mumtaz Tarar; [2011]
    Nyckelord :Asymmetric Doherty Power amplifier;

    Sammanfattning : Power amplifiers are an indispensible part of the wireless communication systems. Conventional PAs provide peak efficiency at peak output power which is obtained at a certain fixed optimum resistance. These kind of amplifiers are normally called switched-mode power amplifiers (SMPAs) and are used for constant envelope signals. LÄS MER

  7. 15. Simulation of cubic GaN growth in SA MOVPE

    Master-uppsats, Institutionen för fysik, kemi och biologi

    Författare :Daniel Nilsson; [2009]
    Nyckelord :simulation; gallium nitride; SAG MOVPE; anisotropic;

    Sammanfattning : In this work growth of cubic GaN in the selective area (SA) MOVPE process is simulated. The simulations are restricted to small pattern SA MOVPE growth. In this case the traditional MOVPE growth and the enhanced growth caused by surface diffusion are important growth factors. LÄS MER