title: Electrical transport of bottom-up grown single-crystal Si(1-x)Ge(x) nanowire.
abstract: In this work, we fabricated an Si(1-x)Ge(x) nanowire (NW) metal-oxide-semiconductor field-effect transistor (MOSFET) by using bottom-up grown single-crystal Si(1-x)Ge(x) NWs integrated with HfO(2) gate dielectric, TaN/Ta gate electrode and Pd Schottky source/drain electrodes, and investigated the electrical transport properties of Si(1-x)Ge(x) NWs. It is found that both undoped and phosphorus-doped Si(1-x)Ge(x) NW MOSFETs exhibit p-MOS operation while enhanced performance of higher I(on)∼100 nA and I(on)/I(off)∼10(5) are achieved from phosphorus-doped Si(1-x)Ge(x) NWs, which can be attributed to the reduction of the effective Schottky barrier height (SBH). Further improvement in gate control with a subthreshold slope of 142 mV dec(-1) was obtained by reducing HfO(2) gate dielectric thickness. A comprehensive study on SBH between the Si(1-x)Ge(x) NW channel and Pd source/drain shows that a doped Si(1-x)Ge(x) NW has a lower effective SBH due to a thinner depletion width at the junction and the gate oxide thickness has negligible effect on effective SBH.
authors.affiliation: Silicon Nano Device Laboratory, Department of Electrical and Computer Engineering, National University of Singapore, 117576, Singapore.
authors.forename: W F
authors.initials: WF
authors.lastname: Yang
authors.forename: S J
authors.initials: SJ
authors.lastname: Lee
authors.forename: G C
authors.initials: GC
authors.lastname: Liang
authors.forename: S J
authors.initials: SJ
authors.lastname: Whang
authors.forename: D L
authors.initials: DL
authors.lastname: Kwong