Papers by Keyword: Silicon Nanotransistor

Abstract: In silicon nanoscale transistors, dopant (impurity) atoms can significantly affect transport characteristics, in particular at low temperatures. Coupling of neighboring dopants in such devices is essential in defining the properties for transport. In this work, we briefly present a comparison of different regimes of inter-dopant coupling, controlled by doping concentration and, to some extent, by selective, local doping. Tunneling-transport spectroscopy can reveal the energy spectrum of isolated dopants and of strongly-coupled dopant atoms. Interactions of multiple-dopants quantum dots (QDs) and satellite individual dopant-traps, as observed in some devices, can provide further information to bridge such inter-dopant coupling regimes for more advanced applications.

Abstract: . In this paper, in order to determine whether the ballistic current enhancement saturates at very high stress level or can be further improved, the effect of uniaxial stress on the ballistic transport of the double-gated, ultrathin-body p-type silicon nanotransistor is investigated using a self-consistent device simulator, which combines the stress-dependent six-band k.p model and a semiclassical top-of-the-barrier ballistic transport model. Based on a semi-continuum atomistic lattice model, the size-dependent elastic constant correction has been for the first time coupled into this simulator. Our results presented here indicate uniaxial compressive stress at moderate levels improves ballistic performance by about 85% while uniaxial tensile stress slightly reduces ballistic drive current. Interestingly, higher compressively strained channel does not offer higher drive current. Although significant variations in the size-dependent elastic constants are found, the ballistic current shows only a small decrease after considering the elastic constant correction. Furthermore, the competition of injection velocity and carrier density related to hole effective masses is found to play a critical role in determining the performance of the nanotransistors.