Brunbauer Florian M, Bertagnolli Emmerich, Lugstein Alois
Institute for Solid State Electronics, Technische Universität Wien , Floragasse 7, 1040 Vienna, Austria.
Nano Lett. 2015 Nov 11;15(11):7514-8. doi: 10.1021/acs.nanolett.5b03169. Epub 2015 Oct 8.
Electrostatically tunable negative differential resistance (NDR) is demonstrated in monolithic metal-semiconductor-metal (Al-Ge-Al) nanowire (NW) heterostructures integrated in back-gated field-effect transistors (FETs). Unambiguous signatures of NDR even at room temperature are attributed to intervalley electron transfer. At yet higher electric fields, impact ionization leads to an exponential increase of the current in the ⟨111⟩ oriented Ge NW segments. Modulation of the transfer rates, manifested as a large tunability of the peak-to-valley ratio (PVR) and the onset of impact ionization is achieved by the combined influences of electrostatic gating, geometric confinement, and heterojunction shape on hot electron transfer and by electron-electron scattering rates that can be altered by varying the charge carrier concentration in the NW FETs.
在集成于背栅场效应晶体管（FET）中的单片金属 - 半导体 - 金属（Al - Ge - Al）纳米线（NW）异质结构中展示了静电可调负微分电阻（NDR）。即使在室温下，NDR的明确特征也归因于谷间电子转移。在更高的电场下，碰撞电离导致<111>取向的Ge NW段中的电流呈指数增加。通过静电门控、几何限制和异质结形状对热电子转移的综合影响以及通过改变NW FET中的载流子浓度可以改变的电子 - 电子散射速率，实现了转移速率的调制，表现为峰谷比（PVR）的大可调性和碰撞电离的起始。
