A complete understanding of the hot carrier degradation problem in sub-micron 0.25um lateral doped drain (LDD) MOSFETs is presented in this work. First we discuss the degradation mechanisms observed under, for circuit operation, somewhat artificial but well-controlled uniform-substrate hot electron and substrate hot-hole injection conditions. Then the more realistic case of static channel hot carrier degradation is treated, and some important process-related effects are illustrated, followed by the behavior under the most relevant case for real operation, namely dynamic degradation. An Accurate and practical parameter extraction is used to obtain the LDMOS transistors model parameters, with the experiment verification. Good agreement between the model simulation and experiment is achieved. The gate charge transfer performance is examined to demonstrate the hot carrier effect. Furthermore, In order to understand the dynamic stress on the LDMOS transistors and its effect on RF circuit, the hot-carrier injection experiment in which dynamic stress with different duty cycle applied to a LDMOS transistor is presented. A Class-C power amplifier is used to as an example to demonstrate the effect of dynamic stress on RF circuit performance. Finally, the strategy for improving hot carrier reliability and a forecast of the hot carrier reliability problem for nano-technologies are discussed.

• Major: Electrical Engineering
• Educational Career:
  • B.A., Zhejiang University, Hangzhou, China, 1998
  • M.S.T., Zhejiang University, Hangzhou, China, 2001
• Committee in Charge:
  • Dr. J.S. Yuan
  • Dr. Thomas Wu
  • Dr. John Shen
  • Dr. Lee Chow