First of all I would like to express my gratitude to Prof. Siegfried Selberherr who is responsible for the extraordinary computing environment and the excellent infrastructure at the Institute for Microelectronics. By always maintaining the right balance between freedom and pressure he guides his students to achieve the best possible work. The strong cooperation with industry partners from all over the world allows to get a very good insight into the semiconductor business. I am also very grateful to Prof. Dietmar Dietrich who was willing to serve on my examining committee on a very short notice.

Of all my colleagues I would like to express special thanks to Andreas Hössinger who has contributed in countless ways to this work. Many fruitful discussions about design and implementation issues originated from him and steadily improved this work. I also owe my roommate C. Heitzinger for contributing to this work and for pointing out the merits of the Lisp programming language to a poor C/C++ programmer.

H. Ceric participated in several technical discussions and helped me seeing many things from a more abstract viewpoint. Thanks also go to R. Klima for never being tired of helping others, and to R. Rodriguez-Torrez for providing us with the best Tequila of the world. I am also indebted to C. Troger who acted as a proof reader of last resort.

I also would like to thank J. Cervenka, K. Dragosits, C. Harlander, R. Kosik, V. Palankovski, and R. Sabelka who always know when it is time for the last beer, and P. Fleischmann who really knows how to play computer games. Thanks also to all other members of the Institute for Microelectronics for providing help in many situations and for being good company throughout the time at the institute.

I am also very grateful to SONY Corporation, at Atsugi Technology Center, Japan for their cooperation. I will never forget the TCAD group under the supervision of Mikio Mukai who introduced me to the Japanese culture.

I would also like to thank my Diplomands C. Weichselbaum, C. Köhle, C. Hollauer, M. Bacher, W. Wessner, and S. Holzer who endured and survived many long lasting meetings and discussions.

Last but not least I would like to thank my family, foremost my wife Kathrin for patiently tolerating my often bad temper especially in the very final phase of this work. I also thank my parents for their never ending support of all my endeavors.