is Íslenska en English

Lokaverkefni (Doktors)

Háskóli Íslands > Verkfræði- og náttúruvísindasvið > Doktorsritgerðir - Verkfræði- og náttúruvísindasvið >

Vinsamlegast notið þetta auðkenni þegar þið vitnið til verksins eða tengið í það:

  • Titill er á ensku Growth of Functional Thin Films by HiPIMS: Fundamentals, Challenges, Applications
  • Doktors
  • Útdráttur er á ensku

    Thin film materials technology is the fundament of all current modern technologies such as electronics, computers, data storages, displays, mobile devices, and Internet network communications. Numerous techniques are available to grow high-quality thin films, such as chemical vapor deposition, thermal evaporation, atomic layer deposition, and sputtering. Magnetron sputtering is the most versatile technique for deposition of thin films. It can be sub-categorized to various methods such as dc magnetron sputtering (dcMS), rf magnetron sputtering (rfMS) and high power impulse magnetron sputtering (HiPIMS).
    This thesis presents the experimental study and the instrumental development for the advancement of the knowledge in the difference of using conventional dcMS and HiPIMS methods to grow films. The experimental study includes materials such as Mo/V superlattices, TiN, TiO2, and SiO2. New measurement methods have been developed in addition to study the early stage of the growth of thin film using in-situ resistance measurements. The advances in measurement methods consist of new high speed sampling hardwares along with LabVIEW software programmed and tested to acquire every detail of each applied HiPIMS pulse during growth.
    In the first experimental part, the initial stages of growth were investigated for TiN thin films. The experiment was done for both HiPIMS and dcMS on different substrates at different growth temperatures. The growth by both methods was also compared for various deposition angles. Moreover, transition of the grown films from epitaxial to texture was observed where the built-up charge on the mask changes the energy spectra of the incoming flux of materials.
    In the second part, the challenges for the growth of TiO2 were studied by the HiPIMS method. Systematic study of oxygen flow, frequency, and current on the plasma power were performed. A new periodic runaway of plasma was observed and characterized when oxygen partial pressure was increased to certain level. Therefore stable plasma or periodic runaway was found in a certain range of pulsing frequencies for every oxygen pressure settings. For growth of a multilayer containing a TiO2 layer, the effect of shutter operation on the growth rate and plasma stability was studied. Also, TiO2/SiO2 Bragg mirrors were grown and the behavior of resonant photon tunneling was investigated.
    In the third part, a HiPIMS/dcMS comparative study was performed on the growth of Mo/V metallic superlattice structures at various growth temperatures. Different combinations of the methods for growth of the superlattice were compared.

Tengd vefslóð: 
  • 31.3.2015

Skráarnafn Stærð AðgangurLýsingSkráartegund 
thesis_ses_b5.pdf21.97 MBOpinnHeildartextiPDFSkoða/Opna