First and foremost I want to thank all members of the Institute for Microelectronics for providing an excellent and inspiring working atmosphere. Hours of discussion, teamwork and wide spread fundamental knowledge are the basics of successfully finishing doctoral studies. Therefore I would like to say my special thanks to the head of the Institute, Professor Siegfried Selberherr, who is not only responsible for a free scope of one's abilities, but also offers an optimum of equipment that is indisputable necessary to keep the pace of advance in research engineering. His international reputation enables his co-workers an insight into problems and requirements of semiconductor industry and offers them to keep in touch with real-world problems.
Of all my colleagues my very special thanks have to be expressed to Ernst Leitner, who introduced me into the mysteries of numerical calculations. For nearly three years we had an intense cooperation, and I did not only win an excellent technical colleague but most important also a friend. I also want to thank my room mate Robert Mlekus, who sometimes spent nights of work to solve a definite problem. Rainer Sabelka, Richard Plasun and Rudi Strasser have always been helpful in system dependent questions and Gerhard Schrom had always an adequate `Ersatzschaltbild' for any problem. Andreas Hössinger introduced me to the ion implantation algorithms and he was always willing to help in any problem.
I owe my special gratitude to my wife Verena, who had not only to keep an eye on our two children but also to bear my day- and night-long struggles with the computer. Thanks for your endless patience and infinite love.
Finally, I want to thank my parents who made all of this possible, and are a lifetime backing, no matter whether concerning private questions or career decisions.