Impact of Strain on the Performance of Ge-Si Core-Shell Nanowire Field Effect Transistors

The performances of Ge-Si core-shell nanowire field effect transistors are evaluated based on a semiclassical ballistic transport model and a phonon-limit model. The valence band structures of Ge-Si core-shell nanowires are calculated by using a k.p method including the strain effect. Three new findings are presented: 1) Strain induces the top valence subbands of Ge core moving-up and substantial band warping; 2) at ballistic transport limit, strain-dependence of current is structure dependence. The strain can remarkably enhance current, but the enhancement can be suppressed by electrostatic effect; 3) at phonon scattering limit, strain causes the enhancement of hole effective mobility of the NW FETs, reaching about 260% at low effective electrical field.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000265829300042&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Engineering, Electrical & ElectronicPhysics, AppliedCPCI-S(ISTP)