Surfacepotential Solution
for Generic Undoped MOSFETs with Two Gates
W. Z. Shangguan, Xing Zhou,
Senior
Member, IEEE, Karthik Chandrasekaran, Zhaomin Zhu, Subhash C. Rustagi,
Senior
Member, Siau Ben Chiah, Guan Huei See
IEEE Transactions on Electron Devices,
Vol.
54, No. 1, pp.
169172, Jan. 2007
(Manuscript received May 19, 2006; revised
September 14, 2006.)
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Abstract
We present a rigorously derived analytical Poisson solution for undoped
semiconductors and apply the general solution to the generic MOSFETs with
two gates, unifying different types such as silicononinsulator (SOI),
symmetric and asymmetric double gate (sDG, aDG) structures. The
NewtonRaphson (NR) method is used to solve the surfacepotential equations
resulting from the application of the boundary conditions to the general
Poisson solution, with an initial guess very close to the exact solution.
The universal initial guess can be used as an approximate explicit solution
for fast evaluation while the iterative solution for benchmark tests.
The results demonstrate unification of surfacepotential solutions
having an accuracy of 10^{15} V for SOI, aDG, and sDG MOSFETs,
achieved with 2 to 6 iterations., Furthermore, the explicit solution yields
less than 3.5% error for backtofront gate oxide thickness ratios larger
than 25.
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Citation

J. He, W. Bian, Y. Chen, B. Li, Y. D. Tao, and Y. Wei, "Carrierbased
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