I must firstly thank my supervisor Prof. Selberherr who deserves my greatest thanks, since he provided me with an incredible amount of support, encouragement, and guidance in development of my research work for about four years. I am not only deeply indebted to him, but also to Prof. Langer, and Prof. Grasser for providing an excellent atmosphere for research and keeping away PhD students from administrative and bureaucratic wattles. I also thank Prof. Riedling for his preparedness to participate in the examining committee.
Throughout these years I had interesting discussions and funny moments with many colleagues at our institute and sometimes by our joint participation of conferences. My thanks go to all of them including Alex, Andi H., Andi G., Artur, Cerv, Christian Ha., Christian Ho., Clemens, Elaf, Enzo, Gerhard, Gregor, Hajdin, Jong Mun, Li, Mahdi, Markus, Martin, Michael, Mixi, Oliver, Peter, Philipp, Rene, Robert E., Robert Kl., Robert Ko., Robert W., Saba, Sid, Stefan, Stephan, Tes, Tibor, and Vassil.
My best thanks go to Philipp, Rene, and Tibor, who investigated much time to carefully read the whole work and gave me advice. I also thank Hajdin and Stefan for their advice on Chapter 2 and Chapter 4, respectively. I would like to thank Yasi who corrected the first version of my abstract in German.
My special thanks go to Clemens for not only reading this work, but also for our valuable discussions, his ideas, constructive comments, and for inducing optimism in me while working at the institute together and even after that.
This thesis was enriched significantly by interesting discussions with Dr. Puchner, Dr. Badrieh, and Dr. Parhami from Cypress Semiconductor Corporation (San Jose, CA, USA) related to the applications of our topography simulator for the design of interconnect lines.
I also thank Dr. Leicht, Dr. Häberlen, and Dr. Fugger from Infineon Technologies (Villach, Austria) for constructive discussions during our quarterly Christian Doppler Laboratory meetings that helped me to develop and implement new physical deposition models.
In addition, I thank Tamaoki-san and Takase-san from Toshiba R&D Center (Kawasaki, Tokyo) for their helpful advice regarding the simulation of etching processes.
Last, but not least, I would like to thank my family in Babol for years of love and support, and my cousins Dr. Mahmoud Nikbakht Tehrani and Dipl.-Ing. Mohammad Nikbakht Tehrani in Vienna, for continuous encouragement.