Atomistic simulation of phonon and alloy limited hole mobility in Si1-xGex nanowires

作者：Mehrotra Saumitra^*; Long Pengyu; Povolotskyi Michael; Klimeck Gerhard

来源：Physica Status Solidi-Rapid Research Letters, 2013, 7(10): 903-906.

DOI：10.1002/pssr.201307124

• SiGe
• alloys
• phonons
• carrier mobility
• nanowires

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 sp(3)d(5)ds*-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, leading 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.

• 出版日期2013-10