Influence of the Ge concentration on the threshold voltage and subthreshold slope of nanoscale vertical Si/SiGe pMOSFETs

  • N. Collaert
  • K. De Meyer
Conference paper


An analytical model has been set up to investigate the influence of SiGe in the source on the threshold voltage and subthreshold behaviour of heterojunction pMOSFETs. The use of SiGe in the source region of the pMOSFET introduces an extra degree of freedom for fine-tuning of the subthreshold and on-state behaviour of the devices. It will be shown that the short channel behaviour of these devices is greatly improved in comparison with vertical homojunction Si structures. Careful design and optimisation of these devices show that the use of Ge is only advantageous for sub 0.1 µm devices. Structures with channel lengths down to 30 nm exhibit promising characteristics.


Threshold Voltage Channel Length Short Channel SiGe Layer Subthreshold Slope 
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Copyright information

© Springer-Verlag/Wien 1998

Authors and Affiliations

  • N. Collaert
    • 1
  • K. De Meyer
    • 1
    • 2
  1. 1.IMEC, ASP divisionLeuvenBelgium
  2. 2.ESAT, K.U.LeuvenHeverleeBelgium

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