Ge Profile for Minimum Neutral Base Transit Time in Si/Si1-yGey Heterojunction Bipolar Transistors

  • Wolfgang Molzer
Conference paper


A simple but effective numerical method for the determination of Ge profiles leading to minimum neutral base transit time τ B is presented. The profiles under consideration have been taken from a large general class of functions. The resulting profiles show that significant reductions in σ B can be achieved when they are compared to other investigated profile types. Moreover the position dependence of these optimum profiles has a simple structure. Thus there are no additional technological difficulties for their realization.


Bipolar Transistor Doping Profile Heterojunction Bipolar Transistor Optimum Profile Intrinsic Carrier Concentration 
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Copyright information

© Springer-Verlag Wien 1995

Authors and Affiliations

  • Wolfgang Molzer
    • 1
    • 2
  1. 1.Corporate Research and DevelopmentSIEMENS AG, ZFE T ME 25MunichGermany
  2. 2.Institut für Theoretische PhysikLeopold-Franzens-Universität InnsbruckInnsbruckAustria

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