Search for dissertations about: "electron and hole mobility"

Showing result 1 - 5 of 19 swedish dissertations containing the words electron and hole mobility.

  2. 1. Detection and removal of traps at the SiO2/SiC interface

    Author : Halldor Olafsson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; interface states; thermally stimulated current TSC ; positron annihilation spectroscopy PAS ; silicon carbide SiC ; metal-oxide-semiconductor field-effect transistor MOSFET ; transmission electron microscopy TEM ; deep level transient spectroscopy DLTS ; metal-oxide-semiconductor MOS ; field-effect mobility; capacitance-voltage C-V ;

    Abstract : The interface between silicon dioxide (SiO2) and silicon carbide (SiC) is at the heart of the SiC metal-oxide-semiconductor field-effect (MOSFET) transistor. The technology to produce a high quality SiO2/SiC interface does not exist today, hampering further development of the SiC MOSFET. READ MORE

  4. 2. Effects of impurities on charge transport in graphene field-effect transistors

    Author : Marlene Bonmann; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; carrier transport; electron and hole mobility; impurities; traps; graphene; field-effect transistors; microwave devices; saturation velocity; remote phonons;

    Abstract : In order to push the upper frequency limit of high speed electronics further, thereby extending the range of applications, new device technologies and materials are continuously investigated. The 2D material graphene, with its intrinsically extremely high room temperature charge carrier velocity, is regarded as a promising candidate to push the frequency limit even further. READ MORE

  5. 3. Electron transport properties of graphene and graphene field-effect devices studied experimentally

    Author : Youngwoo Nam; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; dual-gated graphene field effect devices; thermopower; quantum Hall effect; graphene; Aharonov-Bohm effect; chemical vapour deposition;

    Abstract : This thesis contains experimental studies on electronic transport properties of graphene with the Aharonov-Bohm (AB) effect, thermopower (TEP) measurements, dual-gated graphene field effect devices, and quantum Hall effect (QHE). Firstly, in an effort to enhance the AB effect in graphene, we place superconducting-metal (aluminium) or normal-metal (gold) mirrors on the graphene rings. READ MORE

  6. 4. Hole Transport Materials for Solid-State Mesoscopic Solar Cells

    Author : Lei Yang; Anders Hagfeldt; Erik Johansson; Gerrit Boschloo; Fengling Zhang; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; mesoscopic solar cells; solid-state dye-sensitized solar cells; organometallic halide perovskite; hole transport materials; mesoporous TiO2; conjugated polymer; sensitizer; transient absorption spectroscopy; photo-induced absorption spectroscopy; in-situ photoelectrochemical polymerization; spiro-OMeTAD; P3HT; TPAA; MeO-TPD; bis-EDOT; DEH; Li ion migration; charge recombination; electron lifetime;

    Abstract : The solid-state mesoscopic solar cells (sMSCs) have been developed as a promising alternative technology to the conventional photovoltaics. However, the device performance suffers from the low hole-mobilities and the incomplete pore filling of the hole transport materials (HTMs) into the mesoporous electrodes. READ MORE

  7. 5. Theoretical studies of lattice- and spin-polarons

    Author : Nina Bondarenko; Olle Eriksson; Natalia Skorodumova; Manuel Pereiro; Maria Roser Valenti Vall; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Polaron; Nonlinear Schrödinger Equation; Nonlocality; Solitons; Integrable systems; Quantum field theory low energy ; Electron-phonon interaction; Density functional theory; Electronic structure of atoms and molecules; Spin-polaron; Langevin equation; Transport properties; Hubbard model; Heisenberg lattice; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Abstract : Theoretical studies of lattice- and spin-polarons are presented in this thesis, where the primary tool is ab-initio electronic structure calculations. The studies are performed with employment of a variety of analytical and computational methods. READ MORE