In this work, the consequence of the high band-edge density of states on the carrier statistics and quantum capacitance in transition metal dichalcogenide two-dimensional semiconductor devices is explored. The study questions the validity of commonly used expressions for extracting carrier densities and field-effect mobilities from the transfer characteristics of transistors with such channel materials. By comparison to experimental data, a new method for the accurate extraction of carrier densities and mobilities is outlined. The work thus highlights a fundamental difference between these materials and traditional semiconductors that must be considered in future experimental measurements.
Integrating ferroelectric negative capacitance (NC) into the field-effect transistor (FET) promises to break fundamental limits of power dissipation known as Boltzmann tyranny. However, realizing the stable static negative capacitance in the non-transient non-hysteretic regime remains a daunting task. The problem stems from the lack of understanding of how the fundamental origin of the NC due to the emergence of the domain state can be put in use for implementing the NC FET. Here we put forth an ingenious design for the ferroelectric domain-based field-effect transistor with the stable reversi…
When transistor gate insulators have nanometer-scale equivalent oxide thickness (EOT), the gate capacitance ($C_\textrm{G}$) becomes smaller than the oxide capacitance ($C_\textrm{ox}$) due to the quantum capacitance and charge centroid capacitance of the channel. Here, we study the capacitance of monolayer MoS$_\textrm{2}$ as a prototypical two-dimensional (2D) channel while considering spatial variations in the potential, charge density, and density of states. At 0.5 nm EOT, the monolayer MoS$_\textrm{2}$ capacitance is smaller than its quantum capacitance, limiting the single-gated $C_\text…
We analyze the distributions of electric potential and field, polarization and charge, and the differential capacitance of a silicon metal-oxide-ferroelectric field effect transistor (MOSFET), in which a gate insulator consists of thin layers of dielectric SiO2 and weak ferroelectric HfO2. It appeared possible to achieve a quasi-steady-state negative capacitance of the HfO2 layer, C_(HfO_2 )<0, if the layer thickness is close to the critical thickness of the size-induced ferroelectric-paraelectric phase transition. The quasi-steady-state negative capacitance, being a very slow-varying transien…
High mobility and high on/off ratio field-effect transistors based on chemical vapor deposited single-crystal MoS2 grains
我们报告了场效应晶体管（FET）与单晶二硫化钼（MoS 2）的化学气相沉积（CVD）合成的通道。对于双层MoS 2 FET，迁移率为~17 cm ~ 2 V ~（-1）s ~（-1），开/关电流比为~108，这比基于CVD多晶MoS 2膜的FET高得多。通过避免由转移过程引入的晶界和污染的有害影响，直接沉积在SiO2上的CVD MoS 2原子层的质量与最佳剥离的MoS 2薄片相当。结果表明，CVD法是制备高质量MoS_2原子层的一种可行方法。
Mobility-dependent Low-frequency Noise in Graphene Field Effect Transistors
在300 K ~ 30 K的温度范围内，研究了悬置和衬底上石墨烯场效应晶体管的低频1/f噪声及其与栅电压的关系。我们发现远离Dirac点的噪声幅度可以用广义Hooge关系来描述，其中Hooge参数αH不是常数，而是随器件迁移率单调减小，具有与样品和温度无关的普适依赖性。αH的值也受无序动力学的影响，这并不反映在直流输运特性中，而是随样品和温度而变化。我们属性的栅极电压依赖的噪声幅度的不同行为的相对贡献从各种散射机制，并在狄拉克点附近的载流子不均匀性所造成的潜在波动。悬浮石墨烯器件的较高载流子迁移率导致1/f噪声的值显著低于在衬底上石墨烯器件和大多数传统电子材料中观察到的值。
High Mobility Ambipolar MoS2 Field-Effect Transistors: Substrate and Dielectric Effects
我们在二氧化硅和聚甲基丙烯酸甲酯（PMMA）衬底上制作了二硫化钼场效应晶体管，并在四探针配置中测量了载流子迁移率。对于SiO2上的多层MoS 2，迁移率为30-60 cm 2/Vs，与厚度（15-90 nm）相对无关，并且大多数器件表现出单极n型行为。相比之下，PMMA上的多层MoS 2显示出随厚度增加的迁移率，在厚度约50 nm处高达470 cm 2/Vs（电子）和480 cm 2/Vs（空穴）。迁移率对厚度的依赖性指向在增加迁移率中的块状MoS 2的长程介电效应。
Single crystal field-effect transistors based on an organic selenium-containing semiconductor
我们报道了基于二苯基苯并二硒（DPh-BDSe）的单晶场效应晶体管（FET）的制备和表征。这些有机场效应晶体管（OFFET）用作p沟道累积模式器件。在室温下，对于最好的器件，阈值电压小于-7V，并且载流子迁移率几乎与栅极偏压无关，范围从1 cm 2/Vs到1.5 cm 2/Vs，取决于源漏偏压。通过冷却到室温以下，迁移率略有增加，并且在280 K以下降低。
Dielectric Deposition Enhanced Crystallization in Atomic-Layer-Deposited Indium Oxide Transistors Achieving High Gated-Hall Mobility Exceeding 100 cm2/Vs at Room Temperature
High-Mobility Indium Native Oxide Transistors via Liquid-Metal Printing in Air
The Australian National University（澳大利亚国立大学）；University of New South Wales (UNSW Sydney)（新南威尔士大学）；Australian National Fabrication Facility, Research School of Physics, The Australian National University（澳大利亚国立大学物理研究学院澳大利亚国家制造设施）
Novel High-Mobility Field-Effect Transistors Based on Transition Metal Dichalcogenides
我们报道了基于过渡金属二硫属化物的新型场效应晶体管（FET）的制备。这些层状无机半导体的单晶的独特结构使得能够制造具有固有低场效应阈值和高载流子迁移率的FET，其与最好的单晶Si FET中的迁移率相当（室温下基于WSe 2的FET中的p型电导率高达500 cm 2/Vs）。这些新颖的FET展示了双极操作。由于机械柔性，它们在“柔性”电子产品中具有应用潜力。
Realization of a High Mobility Dual-gated Graphene Field Effect Transistor with Al2O3 Dielectric
我们制作和表征双栅石墨烯场效应晶体管（FET）使用氧化铝作为顶栅电介质。我们使用薄Al膜作为成核层，以使Al 2 O3的原子层沉积。我们的器件在室温下显示出超过8,000 cm 2/Vs的迁移率值，这一发现表明顶栅叠层不会显著增加载流子散射，从而降低器件特性。我们提出了一个设备模型，以适应使用一个单一的流动性值的实验数据。
An Improved Process for Fabricating High-Mobility Organic Molecular Crystal Field-Effect Transistors
在本文中，我们提出了一种改进的方法，用于生产弹性体晶体管邮票和高迁移率的有机场效应晶体管（FET）的半导体并苯分子晶体的基础上。特别地，我们已经消除了使用硅烷化的Si晶片来固化印模以及处理易碎的微米厚度的聚二甲基硅氧烷（PDMS）绝缘膜并将其无气泡地层压在PDMS晶体管印模上的需要。我们发现，尽管改变了设计，更粗糙的PDMS表面，以及在空气中对器件进行层压和测量，我们仍然实现了10 cm^2/Vs量级的电迁移率，与有机FET的当前技术水平相当。我们的器件显示空穴导电，阈值电压为-9V，对应的陷阱密度为1.4 x 10^10 cm^-2。
Carrier Transport in High Mobility InAs Nanowire Junctionless Transistors
理解和模拟纳米线晶体管性能极限的能力是设计下一代器件的关键。在这里，我们报告的高迁移率结无栅全包围纳米线场效应晶体管的载流子迁移率在室温下达到2000 cm 2/V.s的研究。依赖于温度的运输测量揭示了激活运输在低温下由于表面捐助者，而在室温下的运输表现出扩散行为。从电导率数据中，提取的值的声速在InAs纳米线被发现是一个顺序小于散装。这种低声速归因于普遍出现在这些纳米线中的扩展的晶体缺陷。分析温度相关的迁移率数据，我们确定了关键的散射机制限制在这些纳米线的载流子传输。最后，使用这些散射模型，我们进行漂移扩散的纳米线场效应晶体管的输运模拟和比较与实验测量的设备性能。我们的器件建模提供了深入了解InAs纳米线晶体管的性能限制，并可用作基于MEMS的集成电路的预测方法。
Field-effect transistors made of wide-bandgap semiconductors can operate at high voltages, temperatures and frequencies with low energy losses, and have been of increasing importance in power and high-frequency electronics. However, the poor performance of p-channel transistors compared with that of n-channel transistors has constrained the production of energy-efficient complimentary circuits with integrated n- and p-channel transistors. The p-type surface conductivity of hydrogen-terminated diamond offers great potential for solving this problem, but surface transfer doping, which is commonl…
