MoS2 MOSFET 的沟道长度缩放。

Channel length scaling of MoS2 MOSFETs.

机构信息

School of Electrical and Computer Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47906, USA.

出版信息

ACS Nano. 2012 Oct 23;6(10):8563-9. doi: 10.1021/nn303513c. Epub 2012 Sep 12.

DOI:10.1021/nn303513c

PMID:22957650

Abstract

In this article, we investigate electrical transport properties in ultrathin body (UTB) MoS(2) two-dimensional (2D) crystals with channel lengths ranging from 2 μm down to 50 nm. We compare the short channel behavior of sets of MOSFETs with various channel thickness, and reveal the superior immunity to short channel effects of MoS(2) transistors. We observe no obvious short channel effects on the device with 100 nm channel length (L(ch)) fabricated on a 5 nm thick MoS(2) 2D crystal even when using 300 nm thick SiO(2) as gate dielectric, and has a current on/off ratio up to ~10(9). We also observe the on-current saturation at short channel devices with continuous scaling due to the carrier velocity saturation. Also, we reveal the performance limit of short channel MoS(2) transistors is dominated by the large contact resistance from the Schottky barrier between Ni and MoS(2) interface, where a fully transparent contact is needed to achieve a high-performance short channel device.

摘要

在本文中，我们研究了具有从 2μm 缩小到 50nm 范围的沟道长度的超薄体（UTB）MoS2 二维（2D）晶体的电输运性质。我们比较了具有不同沟道厚度的 MOSFET 组的短沟道行为，并揭示了 MoS2 晶体管对短沟道效应的优异免疫力。即使在使用 300nm 厚的 SiO2 作为栅介质的情况下，在厚度为 5nm 的 MoS2 2D 晶体上制造的 100nm 沟道长度（L(ch)）的器件上，我们也没有观察到明显的短沟道效应，其电流开关比高达~109。我们还观察到由于载流子速度饱和，随着连续缩小短沟道器件的导通电流饱和。此外，我们揭示了短沟道 MoS2 晶体管的性能极限受到 Ni 和 MoS2 界面肖特基势垒之间大接触电阻的支配，需要完全透明的接触才能实现高性能的短沟道器件。