JSTS:Journal of Semiconductor Technology and Science

The Institute of Electronics and Information Engineers (대한전자공학회)
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Poly-crystalline Silicon Thin Film Transistor: a Two-dimensional Threshold Voltage Analysis using Green's Function Approach

  • Sehgal, Amit (Department of Physics and Electronics, Hansraj College, University of Delhi) ;
  • Mangla, Tina (Semiconductor Device Research Laboratory, Department of Electronic Science, University of Delhi south Campus) ;
  • Gupta, Mridula (Semiconductor Device Research Laboratory, Department of Electronic Science, University of Delhi south Campus) ;
  • Gupta, R.S. (Semiconductor Device Research Laboratory, Department of Electronic Science, University of Delhi south Campus)
  • Published : 2007.12.31
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Abstract

A two-dimensional treatment of the potential distribution under the depletion approximation is presented for poly-crystalline silicon thin film transistors. Green's function approach is adopted to solve the two-dimensional Poisson's equation. The solution for the potential distribution is derived using Neumann's boundary condition at the silicon-silicon di-oxide interface. The developed model gives insight into device behavior due to the effects of traps and grain-boundaries. Also short-channel effects and drain induced barrier lowering effects are incorporated in the model. The potential distribution and electric field variation with various device parameters is shown. An analysis of threshold voltage is also presented. The results obtained show good agreement with simulated results and numerical modeling based on the finite difference method, thus demonstrating the validity of our model.

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References

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