Sökning: "2DEG density"

Visar resultat 6 - 10 av 14 avhandlingar innehållade orden 2DEG density.

  1. 6. Optimization of Ohmic Contacts and Surface Passivation for ‘Buffer-Free’ GaN HEMT Technologies

    Författare :Chen Ding Yuan; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; QuanFINE; passivation; GaN HEMT; pretreatment; ohmic contact;

    Sammanfattning : Gallium nitride high electron mobility transistors (GaN HEMTs) draw attention from high frequency and high power industries due to unique properties including high electron mobility and saturation velocity combined with high breakdown voltage. This makes GaN HEMTs suitable for power devices with high switching speed and high frequency applications with high power density requirements. LÄS MER

  3. 7. Connected by voids: Interactions and screening in sparse matter

    Författare :Kristian Berland; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Using theory and computations, we study structural and electronic properties of nanoscale systems where regions of low density are important for response and function. Materials with such properties are called sparse matter. Examples include assemblies of organic molecules and layered structures like graphite. LÄS MER

  4. 8. Characterization and Analysis of Surface Passivations and Gate Insulators for AlGaN/GaN Microwave HFETs

    Författare :Martin Fagerlind; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HFET; passivation characterization; passivation; AlGaN GaN heterostructure;

    Sammanfattning : The large bandgap of gallium nitride (GaN) and aluminum gallium nitride (AlGaN) offers an inherently high intrinsic breakdown field. When the materials are joined into the AlGaN/GaN heterostructure a 2-dimensional electron gas (2DEG) with a high electron density as well as high electron mobility is generated. LÄS MER

  5. 9. Growth and characterization of SiC and GaN

    Författare :Rafal Ciechonski; Erik Janzén; Sebastian Lourdudoss; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SiC; GaN; Deep level transient spectroscopy; Minority Carrier Transient Spectroscopy; Hall effect; Cathodoluminescence; Scanning electron microscopy; Atomic Force microscopy; sublimation growth; MOCVD; heterostructures; High Electron Mobility transistor; point defects; Material physics with surface physics; Materialfysik med ytfysik;

    Sammanfattning : At present, focus of the SiC crystal growth development is on improving the crystalline quality without polytype inclusions, micropipes and the occurrence of extended defects. The purity of the grown material, as well as intentional doping must be well controlled and the processes understood. LÄS MER

  7. 10. CVD solutions for new directions in SiC and GaN epitaxy

    Författare :Xun Li; Urban Forsberg; Erik Janzén; Henrik Pedersen; Sebastian Lourdudoss; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; CVD; SiC; GaN; epitaxy;

    Sammanfattning : This thesis aims to develop a chemical vapor deposition (CVD) process for the new directions in both silicon carbon (SiC) and gallium nitride (GaN) epitaxial growth. The properties of the grown epitaxial layers are investigated in detail in order to have a deep understanding. LÄS MER