Search for dissertations about: "Ulf Helmersson"

Showing result 6 - 10 of 20 swedish dissertations containing the words Ulf Helmersson.

  2. 6. Electrochromism in Nickel-based Oxides : Coloration Mechanisms and Optimization of Sputter-deposited Thin Films

    Author : Esteban Damián Avendaño Soto; Gunnar Niklasson; Andris Azens; Claes-Göran Granqvist; Ulf Helmersson; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; Nickel based Oxide; Electrochromism; Thin Films; Sputtering; Coloration mechanism; Fysik; Physics; Fysik;

    Abstract : Electrochromic properties of sputter-deposited nickel-based oxide films have been studied with a two-fold goal. From a practical point of view, the optical switching performance has been improved by optimizing the deposition conditions and film stoichiometry with respect to oxygen and hydrogen, and further by adding Mg, Al, Si, Zr, Nb or Ta to the films. READ MORE

  4. 7. Fundamentals of High Power Impulse Magnetron Sputtering

    Author : Johan Böhlmark; Ulf Helmersson; André Anders; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Plasma; Pulsed plasma; High Power Pulsed Magnetron Sputtering; Plasma Characterization; Physics; Fysik;

    Abstract : In plasma assisted thin film growth, control over the energy and direction of the incoming species is desired. If the growth species are ionized this can be achieved by the use of a substrate bias or a magnetic field. Ions may be accelerated by an applied potential, whereas neutral particles may not. READ MORE

  5. 8. Plasma Synthesis and Self-Assembly of Magnetic Nanoparticles

    Author : Sebastian Ekeroth; Ulf Helmersson; Nils Brenning; Franz Faupel; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Plasma; Synthesis; Self-Assembly; Magnetic; Nanoparticles;

    Abstract : Nanomaterials are important tools for enabling technological progress as they can provide dramatically different properties as compared to the bulk counterparts. The field of nanoparticles is one of the most investigated within nanomaterials, thanks to the existing, relatively simple, means of manufacturing. READ MORE

  6. 9. Controlling the growth of nanoparticles produced in a high power pulsed plasma

    Author : Rickard Gunnarsson; Ulf Helmersson; Nils Brenning; Holger Kersten; Linköpings universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Nanotechnology can profoundly benefit our health, environment and everyday life. In order to make this a reality, both technological and theoretical advancements of the nanomaterial synthesis methods are needed. READ MORE

  7. 10. Titanium oxide nanoparticle production using high power pulsed plasmas

    Author : Rickard Gunnarsson; Ulf Helmersson; Grzegorz Greczynski; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : This thesis covers fundamental aspects of process control when growing titanium oxide nanoparticles in a reactive sputtering process. It covers the influence of oxygen containing gas on the oxidation state of the cathode from which the growth material is ejected, as well as its influence on the particles oxidation state and their nucleation. READ MORE