“Kinetics of phase structure during nanostructured Ni:C film growth”

Author, institution: Gediminas Kairaitis, Kaunas University of Technology

Science area, field: Physical Sciences, Physics

The Doctoral Dissertation is available at the library of Kaunas University of Technology (K. Donelaičio St. 20, Kaunas).

Scientific Supervisor:

Prof. Dr. Habil. Arvaidas GALDIKAS (Kaunas University of Technology, Physical Sciences, Physics – 02P).

The Dissertation Defence Board of Physics Science field:

Prof. Dr. Giedrius LAUKAITIS (Kaunas University of Technology, Physical Sciences, Physics – 02P) – chairman;

Prof. Dr. Armuntas BAGINSKAS (Lithuanian University of Health Sciences, Physical Sciences, Physics – 02P);

Prof. Dr. Liudas PRANEVIČIUS (Vytautas Magnus University, Physical Sciences, Physics – 02P);

Dr. Gediminas RAČIUKAITIS (Center for Physical Sciences and Technology, Institute of Physics, Physical Sciences, Physics – 02P);

Prof. Dr. Habil. Sigitas TAMULEVIČIUS (Kaunas University of Technology, Physical Sciences, Physics – 02P).

Annotation:

The aim of this work is to establish the processes occurring during nanocomposite thin films growth by using the models of phase separation and surface segregation in growing films and to identify the factors controlling phase structure of films. The models simulating growth of a binary thin film layer by layer and the processes of phase separation and surface segregation are presented in this work.
The formations of the various columnar, granular-like or layered patterns are shown by the numerical simulations of the presented models. The influence of growth rate, surface diffusion, bulk diffusion, concentrations of the film constituents on the phase structure of thin films is investigated. The simulations of phase separation during thin film growth showed that the phase structure of thin films depends on deposition rate V_ad and diffusion coefficient at the surface layer D₀ (more specifically it depends on the ratio D₀/V_ad) and elemental composition of thin film. The transitions from a granular-like structure to a columnar structure with the columns extending over the whole film thickness were obtained by increasing the ratio D₀/V_ad or by varying concentrations of the film constituents.