Atomistic simulation of phonon and alloy limited hole mobility in Si1−xGex nanowires
نویسندگان
چکیده
The role of alloy and phonon scattering is theoretically explored in 5 nm diameter SiGe nanowires at room temperature. Low field mobility calculations are performed by utilizing sp3d5ds∗-spin-orbit-coupled tight binding model for electronic structure and Boltzmann transport formalism. Three different transport orientations <100>, <110> and <111> are considered. Alloy scattering is found to play an important role in these Si1−xGex nanowires, lending to a characteristic ’U’ shaped mobility curve as a function of alloy composition. It is concluded that to extract any advantage of higher Ge hole mobility by alloying, Ge%>70% is needed. Furthermore, the<111> channel orientation exhibits the highest hole mobility while <100> has the lowest hole mobility for any given alloy composition.
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