迈向高性能p型二维场效应晶体管:接触工程,缩放和兴奋剂
Aaryan Oberoi1, Ying Han1, Sergei P Stepanoff2,3
1Department of Engineering Science and Mechanics, Penn State University, University Park, Pennsylvania 16802, United States.
ACS nano
|October 9, 2023
概括
使用 tungsten diselenide (WSe2) 的高性能 p型场效应晶体管 (FET) 通过优化接触,缩放通道长度和采用单层兴奋剂来开发. 这一突破解决了二维 (2D) 电子的关键挑战.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术纳米技术
背景情况:
- 像MoS2和WS2这样的二维 (2D) 过渡金属二甲基化物 (TMD) 对电子设备有希望,但p型场效应晶体管 (FET) 在性能方面落后.
- 现有的p型二维FET不符合国际设备和系统路线图 (IRDS) 的严格要求.
研究的目的:
- 为了实现高性能的p型FET,使用合成WSe2.
- 为了克服当前p型2DFET的性能限制.
主要方法:
- 这是一个多方面的方法,涉及与 (Pd) 接触工程,通道长度 (Lch) 缩小到~20 nm,以及使用氧化 (WOSe2) 的单层兴奋剂.
- 电气测量,原子成像和严格分析以确定最佳的接触金属和兴奋剂策略.
- 利用双层WSe2的自我限制氧化来产生单层WOSe2用于p型兴奋剂.
主要成果:
- 帕拉 (Pd) 被确定为WSe2的优质接触金属,增强了表皮质,颗粒大小和压缩应变,从而降低了肖特基屏障高度.
- 通过缩放Lch,ON状态的性能提高了~10倍,但超级缩放的FET变得接触有限.
- 单层WOSe2兴奋剂导致了约5倍的ON状态性能提升和约9倍的接触阻力降低.
- 通过Pd接触实现了超级缩放的p型WSe2FET的中位数ON状态电流~10μA/μm.
- 证明了单层兴奋剂策略对其他二维材料 (如MoS2,MoTe2和MoSe2.2) 的适用性.
结论:
- 接触工程,通道长度缩放和单层兴奋剂的组合有效地创造了高性能p型WSe2 FET.
- 开发的技术显著提高了ON状态的性能,并降低了2D FET中的接触电阻.
- 单层兴奋剂策略显示了广泛的适用性,用于增强电子应用的各种2D材料.
相关概念视频
Field Effect Transistor
441
Field-effect transistors (FETs) are integral to electronic circuits and distinguished by their three-terminal setup: the gate, drain, and source. These transistors operate as unipolar devices, which utilize either electrons or holes as charge carriers, in contrast to bipolar transistors, which use both types of carriers. The primary function of the FET is to modulate the flow of these carriers from the source to the drain through a channel. The voltage difference between the gate and source...
441
P-N junction
549
A p-n junction is formed when p-type and n-type semiconductor materials are joined together. At the interface of the p-n junction, holes from the p-side and electrons from the n-side begin to diffuse into the opposite sides due to the concentration gradient. This diffusion of carriers leads to a region around the junction where there are no free charge carriers, known as the depletion region. The charge density within the depletion region for the n-side and p-side can be described by the...
549
MOSFET
491
The Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) plays a pivotal role in modern electronics thanks to its versatility and efficiency in controlling electrical currents. This device, also known as IGFET, MISFET, and MOSFET, has three main terminals: the Source, Drain, and Gate. MOSFETs are classified into n-channel or p-channel types based on the doping characteristics of their substrate and the source or drain regions.
In an n-MOSFET, the structure includes n-type source and drain...
In an n-MOSFET, the structure includes n-type source and drain...
491
MOSFET: Enhancement Mode
364
Enhancement-mode MOSFETs are pivotal components in electronics, distinguished by their capacity to act as highly efficient switches. They are part of the larger family of metal-oxide Semiconductor Field-Effect Transistors (MOSFETs). They are available in two types: p-channel and n-channel, each tailored to specific polarity operations.
In their basic form, enhancement-mode MOSFETs are typically non-conductive when the gate-source voltage (Vgs) is zero. This default 'off' state means no...
In their basic form, enhancement-mode MOSFETs are typically non-conductive when the gate-source voltage (Vgs) is zero. This default 'off' state means no...
364
Biasing of FET
301
Biasing a Junction Field Effect Transistor (JFET) is crucial for setting operational parameters and ensuring efficient functioning in electronic circuits. JFETs are characterized by using a single carrier type in N-channel or P-channel configurations, where the channel is surrounded by PN junctions. These junctions are central to the device's ability to control current flow.
In an N-channel JFET, the structure consists of N-type material forming the channel on a P-type substrate, with the...
In an N-channel JFET, the structure consists of N-type material forming the channel on a P-type substrate, with the...
301
Metal-Semiconductor Junctions
363
The contact of metal and semiconductor can lead to the formation of a junction with either Schottky or Ohmic behavior.
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
363


