Search for dissertations about: "BOMBARDMENT"

Showing result 1 - 5 of 52 swedish dissertations containing the word BOMBARDMENT.

2. 1. Engineered ion-bombardment as a tool in thin film deposition

   Author : Rommel Paulo B. Viloan; Ulf Helmersson; Daniel Lundin; Rainer Hippler; Linköpings universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; HiPIMS; Bipolar HiPIMS; Ion-bombardment; Thin film;

   Abstract : Energetic-ion bombardment has become an attractive route to modify the crystal growth and deposit high quality thin films. In high-power impulse magnetron sputtering (HiPIMS) where the discharge is characterized by a significant amount of ions of the sputter-ejected atoms, energetic-ion bombardment effects could not be underestimated. READ MORE

4. 2. Fundamental Processes in SiO2 under Ion Bombardment

   Author : Harald Jacobsson; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : Investigations of sputtering, electron emission and oxide growth under 40-300 keV H+, He+, N+, Ne+, Ar+, Kr+ and Xe+ ion bombardment of SiO2 are presented in this thesis. To accurately determine SiO2 sputtering yields, a new measurement method was developed where the electron emission was monitored during sputtering through thin SiO2 films on Si substrates. READ MORE

5. 3. The evolution of lunar breccias : U-Pb geochronology of Ca-phosphates and zircon using Secondary Ion Mass Spectrometry

   Author : Fiona Karen Thiessen; Martin Whitehouse; Alexander Nemchin; Victoria Pease; Barbara Cohen; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Moon; impact breccias; Apollo missions; impact event; Late Heavy Bombardment; zircon; Ca-phosphates; U-Pb; SIMS; geochronology; Geology; geologi;

   Abstract : Planetary bodies in our Solar System, including the Moon, were exposed to an intense asteroid bombardment between ~4.5-3.8 Ga, shaping their surfaces and leaving visible “footprints” in the form of large impact basins. The end of this period (~4. READ MORE

6. 4. Nucleation and stress generation in thin films deposited with a pulsed energetic deposition flux

   Author : Daniel Magnfält; Ulf Helmersson; Fridrik Magnus; Linköpings universitet; []
   Keywords : ;

   Abstract : This thesis presents fundamental mechanisms of nucleation and early growth of and stress generation in thin polycrystalline metal films deposited using pulsed energetic deposition fluxes. The effects of a pulsed deposition flux and energetic bombardment on film nucleation was investigated using in situ stress measurements and in situ ellipsometry to determine the film thickness at which the films become continuous. READ MORE

7. 5. Development and tribological characterisation of magnetron sputtered TiB2 and Cr/CrN coatings

   Author : Mattias Berger; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; TiB2; Tribology; Magnetron Sputtering; Materialvetenskap; Materials science; Teknisk materialvetenskap; materialvetenskap; Materials Science;

   Abstract : The aim of this thesis was to develop wear resistant physical vapour deposited coatings of TiB2 as well as multilayers of Cr/CrN. The correlation between deposition parameters and fundamental coating properties such as microstructure, composition, residual stress and hardness has been investigated. READ MORE