CAREER: Rational Design of One-Dimensional Contacts to Two-Dimensional Atomically Thin Heterostructure for High-Performance and Low Noise Field Effect Transistors and Biosensors

本课题研究了具有二维原子薄材料和一维触点的场效应晶体管（fet）。这些晶体管将表现出高性能和低噪声特性，并将为包括生物传感器设备和电路在内的新兴技术奠定基础。虽然硅基电子产品几十年来一直是创新的基础，但由于其固有的晶体对称性和相关的物理和化学性质的瓶颈，它们在原子薄尺寸上的性能会崩溃。该项目研究了石墨烯、六方氮化硼和过渡金属二硫族化物的使用，以形成原子级薄的场效应管。鉴于其前所未有的物理特性，如材料和器件的可调性以及原子水平上的能源效率，这些器件将彻底改变fet在新应用中的使用，这些应用将改变通信、医疗保健和环境传感等行业的电子产品。预计这些设备和部署它们的电路将在物联网（IoT）、工业4.0、数据分析、人工智能和机器学习的发展中发挥重要作用。这个项目将培训下一代研究人员，包括女性科学家和工程师以及那些来自代表性不足的人群的研究人员，在微纳米尺度的科学和工程方面获得解决一些复杂社会问题的专业知识，例如为环境监测和疾病诊断创造传感器。从这个项目中获得的成果将被整合到教育活动中。提出的研究旨在展示高性能和低噪声场效应晶体管器件，该器件将独特地用作高灵敏度生物传感器的平台。本课题的目标是通过理解(1)以低功函数金属和半金属作为源极和漏极的接触工程，合理设计和研究涉及石墨烯、六方氮化硼和过渡金属二硫化物（如二硫化钼）的二维原子薄异质结构场效应晶体管的相关电输运和噪声现象；(2)具有大传递长度和低接触电阻的边缘接触结构；(3)利用同位素纯六方氮化硼介质工程操纵极性声子；(4)开发高灵敏度的SARS-CoV-2抗体/抗原免疫传感器。所有这些成功的关键需要对原子尺度上的材料可调性，量子约束和与能带结构的关系，器件结构和集成，以及电输运和噪声物理之间的相关现象有基本的了解。基于实验设计参数和结果（如双探头与四探头测量设计），将开发出超越传统硅晶体管和生物传感器模型的新器件模型。量子限制物理将被用来证明它们的结构和性质可调性及其与功能（例如，传感特性）的关系。该项目由ECCS和促进竞争研究的既定计划（EPSCoR）共同资助。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Field Effect Transistors (FETs) with two-dimensional atomically thin materials and one-dimensional contacts are studied in this project. These transistors will demonstrate high performance and low noise characteristics and will lay the foundation for emerging technologies including biosensor devices and circuits. Though silicon-based electronics have been the basis for innovation for several decades, their performance at atomically thin dimensions breaks down due to the bottleneck in its intrinsic crystal symmetry and associated physical and chemical properties. This project investigates the use of graphene, hexagonal boron nitride, and transition metal dichalcogenides to form atomically thin FETs. Given their unprecedented physical properties such as material and device tunability and energy efficiency at the atomic level, these devices will revolutionize the use of FETs in new applications that will transform electronics across industries such as communications, healthcare, and environmental sensing. It is expected that these devices and circuits that deploy them will play a great role in the development of internet-of-things (IoT), Industry 4.0, data analytics, artificial intelligence, and machine learning. This project will train next generation researchers, including women scientists and engineers and those from underrepresented populations, in micro-nanoscale science and engineering to gain expertise in addressing some of the complex societal problems such as creating sensors for environmental monitoring to disease diagnostics. The results obtained from this project will be integrated in educational activities. The proposed research aims to demonstrate high performance and low noise field effect transistor devices that will uniquely be used as a platform for highly sensitive biosensors. The objectives of the proposal is to rationally design to study correlated electrical transport and noise phenomena in number of two dimensional atomically thin heterostructure field effect transistors involving graphene, hexagonal boron nitride, and transition metal dichalcogenides (such as molybdenum disulfide) by understanding (1) contact engineering with low work function metals and semimetals as source and drain electrodes, (2) edge contacted architectures with large transfer length and low contact resistance, (3) manipulating polar phonons by dielectric engineering using isotopically pure hexagonal boron nitrides and (4) development of antibody/antigen immunosensors with high sensitivity for SARS-CoV-2. Key to all these successes requires a fundamental understanding in material tunability in atomic scale, quantum confinement and relation to band structure, device architecture and integration, and correlated phenomena between electrical transport and noise physics. Based on experimental design parameters and results (such as a two probe vs. four probe measurement design), new device models beyond the traditional silicon transistor and biosensor model will be developed. Quantum confined physics will be exploited to demonstrate their structure and property tunability and their relation to the functionality (e.g., sensing characteristics).This project is jointly funded by ECCS and the Established Program to Stimulate Competitive Research (EPSCoR).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.