Search for dissertations about: "passivation"

Showing result 1 - 5 of 99 swedish dissertations containing the word passivation.

  2. 1. Passivation of Austenitic Stainless Steel

    Author : Lena Wegrelius; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; stainless steel; chloride; molybdenum; passivation; hydrochloric acid; nitrogen; ESCA; dissolution;

    Abstract : The objective of this thesis is to study the corrosion resistance and passivation of high alloyed austenitic stainless steels exposed to hydrochloric acid. The introductory section gives a background to the subject; electrochemical measurements and surface analysis by the ESCA-technique (Electron Spectroscopy for Chemical Analysis). READ MORE

  4. 2. Termination and passivation of Silicon Carbide Devices

    Author : Maciej Wolborski; Anders Hallén; Jan Szmidt; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Silicon Carbide; SiC; passivation; dielectric materials; Semiconductor physics; Halvledarfysik;

    Abstract : Silicon carbide rectifiers are commercially available since 2001, and MESFET switches are expected to enter the market within a year. Moreover, three inch SiC wafers can be purchased nowadays without critical defects for the device performance and four inch substrate wafers are announced for the year 2005. READ MORE

  5. 3. Characterization and Analysis of Surface Passivations and Gate Insulators for AlGaN/GaN Microwave HFETs

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

    Abstract : 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. READ MORE

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

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

    Abstract : 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. READ MORE

  7. 5. In the confines of Cu(In,Ga)Se2 thin film solar cells with rear surface passivating oxide layers

    Author : Dorothea Ledinek; Marika Edoff; Charlotte Platzer Björkman; Jan Keller; Christian Kaufmann; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Alkali; Alumina; Back contact; CIGS; CIGSe; Hafnia; Passivation; Rear contact; Sodium fluoride; Ultra-thin; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics;

    Abstract : The material supply to build renewable energy conversion systems needs to be considered from both a cost and an energy security perspective. For Cu(In,Ga)Se2 (CIGS) thin film solar cells the use of indium in the absorber layer is most problematic. READ MORE