Acknowledgement

First and foremost I want to express my deepest gratitude to my supervisor and mentor Professor Siegfried Selberherr who not only enabled me to embark on this astonishing journey in the first place but also provided me with unwavering support throughout the entire time. Professor Selberherr allowed me to find my own paths, honed my ability to take on responsibilities, and always - and I mean always - found some kind of error in my manuscripts, continuously improving my eye for details. Without his belief in me and my skills I would not be where I am today.

Karl(i) Rupp deserves my sincere thanks as a colleague with whom I had the pleasure working for over three years. In him I found a colleague who always provided me with his honest opinion in a respectful manner. Karli was always willing to venture out on new (rather time-consuming) side-projects, such as the Google Summer of Code programs which we could claim for our university not just for the first time but also three times in a row (so far..).

I want to thank the informal gentlemen’s club for their support but most of all for great moments and adventures, especially Lado Filipovic (the Canuck), Mihail Nedjalkov (Mixi), Philipp Schwaha (Lord Phil), Stanislav Tyaginov (Stas), Alexander Makarov (Alex), Dmitry Osintsev (Dima), Ivan Starkov (Vanja), Stanislav Vitanov (Stani), Roberto Orio (Mr Brazil), and Johann Cervenka (Cerv). I will never forget looking for the sun in Sozopol, the surprisingly challenging task of finding a suitable restaurant in Kyoto, the slightly disturbing white nights in Saint Petersburg, the challenging trip to Munich, the campaign in Bratislava, the occasional office sessions, and the visits in my hometown.

I also want to express my gratitude to other members of the institute for their support over the recent years, among them are Professor Erasmus Langer, for providing an excellent work environment, Florian Rudolf, for joining our software team and providing a fresh view (also for proof-reading this thesis), Markus Bina, for advanced device simulation knowledge, Franz Schanovsky, for cluster support, Viktor Sverdlov, for honest discussions, Manfred Katterbauer, for maintaining my hardware and enduring my requests, René Heinzl, for igniting my interest in software engineering, and Franz Stimpfl, for the fun we had.

I had the honour of visiting the Device Modelling Group at the University of Glasgow and EPCC at the University of Edinburgh, Scotland, UK in 2012, which was funded by the HPC-Europa2 program. For this, I owe Professor Asen Asenov my most sincere thanks as it would not have been possible without him. Also, I am honoured that Professor Asenov acts as a second examiner for this thesis, which in the light of his undoubtedly tight schedule is no small undertaking. Overall, I want to thank the group members in Glasgow, among them are Stanislav Markov, Gordon Stewart, Ewan Towie, Vihar Georgiev, and Campbell Millar, for extensive talks, their interest in my work, their hospitality, and their support. At EPCC, Catherine Inglis did an amazing job of organizing the overall visit whereas Daniel Holmes and especially Mario Antonioletti devoted their valuable time to discuss my research and possible improvements. I learned a lot about software engineering for supercomputers, which in this case was HECToR.

I also want to express my gratitude to a few additional fellow researchers. A big thanks to Václav Hapla, whom I met the first time at a conference in Helsinki and then again by accident at a summer school in New York City. In the end, he invited me to give a lecture at a workshop at his university in Ostrava. Thank you so much for you hospitality and the opportunity. Also, I am thankful for getting to know Jean Michel (JM) Sellier whom I met at a conference in Madison, Wisconsin and since then stayed in touch. JM and I share the need to support the open source movement in the area of technology computer-aided design. I had the pleasure to get to know Peter Gottschling at a conference in Rhodos in 2010, where we had extensive discussions on software engineering, resulting in me realizing that I have a long way ahead of me.

The projects I participated in and the people I had the honour to meet and work with would not have been possible without the projects provided by publicly funded institutions, such as the European research council, the Austrian science fund, and the partnership for advanced computing in Europe as well as ultimately the tax payers. Thank you for enabling young researchers to develop themselves in an astonishingly fast pacing research environment.

My progress is not only influenced by professional connections but also by a highly supporting social base. By that I mean firstly my dear friends who were always there for me and with whom I spent amazing times, allowing me the occasional much required distance from work. Among them are Mathias (LG), Ralph (Extraordinaire), Thomas (Tommi), Susi (Susi!), Dominik (Ewok), Clemens (Friedrich), Karin (Karin!), Florian (Flo), Philipp (Chip), Georg (Bussi Schorsch), Christian (Puxi), Andreas (Nemsi), and Markus (Gotchy). Thanks for the various oakings, BOBs, gaming sessions, barbecues, and whatnot; I am honoured to call you friends. Secondly, I owe my dear family my deepest gratitude for their unconditional support, most of all my caring mother Margarethe, my unwavering father Josef, my beloved sister Iris (Billi), as well as my extended family around the various clans based in Limberg (the Steinschadens, the Kastners, the Vetters, the Dolezals, and the Goldas), Fahndorf (the Weinbubs, the Hintermayers, and the Hangels), and Tulln (the Grills and the Friedls). Thirdly and most importantly, I thank my smart, lovely, funny, lively, understanding, and caring girlfriend Christiane for enduring me and my devotion to my work.