Acknowledgment

First of all I want to thank all my colleges at the Institute for Microelectronics for providing an excellent and friendly working atmosphere. Particularly I would like to thank Professor Selberherr who is responsible for the remarkable working environment at the institute and for the guidance of his students. By keeping away administrative task from the students and by avoiding bureaucratic wattles he made it possible to concentrate just on the important tasks. His international reputations and his close contacts to the international semiconductor industry offers his co-workers the unique opportunity to gain a lot of experience and to keep in touch with problems at the technological front. But he did not only focus on the skills and experience of the students but also on motivating them to broaden their personality, by giving them the chance to participate in international conferences and international projects.

Of all my colleges my very special thanks have to be expressed to Professor Langer who supported me in a national project I took part in and gave me several suggestions for writing my thesis, to Rainer Sabelka who introduced me to some secrets of UNIX and who was always a very cooperative system-administrator, to my room mate Wolfgang Pyka who precisely reviewed some of my publications and who was very inventive in vitalizing breaks, to Christian Harlander, Johann Cervenka, Thomas Binder and Christian Troger who always took care on the tempers of the computer system, and to Klaus Dragosits, Peter Fleischmann, Heinrich Kirchauer, Robert Kosik, and Rudi Strasser with whom I had several interesting and funny discussions especially during lunch time.

Concerning the technical contribution to my thesis I want to thank Gerhard Hobler, Hannes Stippel and Walter Bohmayr who provided the basis for this work by their doctoral thesis, and to Alexander Burenkov and Klaus Tietzel from the Fraunhofer Institute für Integrierte Schaltungen in Erlangen for several technical suggestions and discussions about new models and algorithms.

I am in debt to the TCAD group at the Atsugi technology center of the Sony semiconductor corporation under the direction of Mikio Mukai for giving me a chance to get an impression of the work in semiconductor industry. Especially I want to thank Mitsunori Kimura for assisting me and giving me an impression of the Japanese way of live.

Last but not least I want to thank my parents for always supporting my personal and academic advancement, and my girlfriend Barbara for her understanding and encouragement.