Even at room temperature, sub-100 ,nm CMOS devices are strongly affected by quantum mechanical effects. In addition to commonly-known energy quantization in the channel, a charge dipole is observed to appear in the poly-gate, which shifts the threshold voltage in a different way from channel quantization. Moreover, due to the multi-dimensional nature of the structure, conventional Schrodinger/Poisson's equation solutions in 1D are no longer adequate for predicting the device characteristics. In this paper, two macroscopic, multi-dimensional quantum transport models, density gradient (DG) and non-equilibrium Green's function (NEGF), are discussed. Validity and application scope are established through comparing to measured data and benchmarking with MIT well-tempered MOSFETs (wtm25 and 90 nm, respectively). It is shown both qualitatively and quantitatively that quantum effects are now required in profile calibration and inverse modeling.
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