Size- and Orientation-Dependent Strain Effects on Ballistic Si p-Type Nanowire Field-Effect Transistors

作者：Baykan Mehmet O^*; Thompson Scott E; Nishida Toshikazu

来源：IEEE Transactions on Nanotechnology, 2012, 11(6): 1231-1238.

DOI：10.1109/TNANO.2012.2222662

• Ballistic transport
• hole current
• nanowire (NW)
• pMOSFET
• strain engineering
• tight binding

The size- and orientation-dependent uniaxial strain effects on ballistic hole transport in nanowire field-effect transistors are investigated using an sp(3)d(5)s*-based tight-binding formalism coupled with a compact electrostatics model and a semiclassical transport model. It is found that the strain-induced reduction of the valence band density of states leads to an increased ballistic hole current. This is explained by the product of a small reduction in hole density and a significant increase in the average ballistic hole velocity under uniaxial compression. While uniaxial compressive strain is beneficial for both < 110 > and < 100 > devices, the strain response of < 110 > nanowires is much larger than their < 100 > counterparts. Ultrascaled < 110 > nanowires have the highest hole drive current under both strained and unstrained conditions, despite the reduction of strain-induced ballistic hole current enhancement for narrower devices.

• 出版日期2012-11