Based on the quasi-3D potential approach, a unified subthreshold-potential, threshold-voltage, and subthreshold-current model is developed for multiple-gate mosfet s including a quadruple-gate, triple-gate, and omega-gate mosfet . This work indicates that the scaling-length-oriented subthreshold current roll-up Δ I sub and threshold voltage roll-off Δ V th provide the physical insight into well-controlled short-channel effects (SCEs) in terms of effective scaling length λ eff according to the scaling factor. Besides the decreased minimum conducting channel potential Φ C ,min, the smaller scaling-length-induced effective channel width/height ( W eff/ H eff) reflects the smaller effective conducting cross-sectional area, which reduces the subthreshold current degradation due to the increased subthreshold resistance R sub. By accounting for the coupling factor in the quasi-3D potential approach, W eff, H eff, and Φ C ,min will be increased to some extent to decrease R sub, which, hence, degrades the subthreshold behavior more extensively in response to SCEs.
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