Poly(ethyleneimine) Doping of CNTFETs: Effect of Solvent and Optimization of Doping Parameters

  • P. R. Yasasvi Gangavarapu
  • M. R. AnjanashreeEmail author
  • Suman Pahal
  • Manoj M. Varma
  • A. K. Naik
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 215)


Carbon Nanotube Field Effect Transistor (CNTFET) when doped with the polymer Poly(ethyleneimine) (PEI) changes its behaviour from p-type to n-type. The solvent used to disperse this polymer plays a very important role in doping process. In this work we report the effect of two solvents: Methanol and DI water. We observe that DI water solvent gives better electrical characteristics such as higher ON current and gives higher yield of n-type CNTFET devices. We have reported the optimization of both the doping time and the concentration of the polymer solution to get the higher yield of n-type CNTFETs.



The authors would like to acknowledge the usage of National Nano fabrication Centre (NNfC) and Micro and Nano Characterization Facility (MNCF) at Centre for Nanoscience and Engineering (CeNSE), Indian Institute of Science (IISc) Bangalore.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • P. R. Yasasvi Gangavarapu
    • 1
  • M. R. Anjanashree
    • 1
    Email author
  • Suman Pahal
    • 1
  • Manoj M. Varma
    • 1
  • A. K. Naik
    • 1
  1. 1.Centre for Nano Science and EngineeringIndian Institute of ScienceBengaluruIndia

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