2D Materials Engineering for Electron Devices

十多年前，石墨烯场效应管的发现促成了2D材料的复兴：由紧密结合的原子堆叠在一起的二维片。层状材料包括绝缘体、半导体、半金属和金属。我的研究计划的长期目标是了解和开发用于电子设备的2D材料的独特性质。在过去的5年里，我的研究小组开发了氧化石墨烯的声学器件，现在正在由初创企业Ora Graphene Audio商业化，利用石墨烯晶体管实现了创纪录的pH传感精度，在低迁移率材料中实现了量子霍尔效应的世界纪录，我们是最早观察到黑磷中2D电荷输运的人之一。基于我们在石墨烯和黑磷方面的专业知识，我的研究计划有三个主要主题：新的2D材料、新的2D晶体管制造技术和新的2D晶体管结构。在第一个主题中，我们将表征SnSe的能带结构和电荷输运特性，SnSe是一种具有创纪录热电优值的黑磷的极性类似物。我们还将剥离超薄的Sb层，Sb是一种比黑磷更重的化合物，在那里，自旋轨道耦合和量子限制之间存在竞争，随着原子层极限的接近，预计会发生半金属到半导体的转变。同时，我们将开发一种倒装芯片方法，使我们能够在完全惰性的环境中用环境敏感的2D材料(如黑磷)制造晶体管，将氧化的有害影响降至最低。最后，我们将开发新的黑磷晶体管结构。这包括了解黑磷中自旋极化电流流动的量子点接触，以及在晶体管运行期间应用斯塔克效应进行带隙调整的双栅晶体管。高资格人员(HQP)将使用包括半导体器件表征工具在内的最先进的研究基础设施进行培训。一个装有光学显微镜、原子力显微镜和剥离工具的手套箱可以制造2D材料晶体管。HQP可以使用共享的设施，如使用电子束光刻和拉曼光谱工具的爱科尔理工学院微细加工实验室。我的团队是塔拉哈西国家强磁场实验室(NHMFL)的定期用户，可以访问世界上最高的静态磁场。我们与世界各地的研究人员保持着积极的合作，他们在分子束外延、扫描调谐显微镜、透射电子显微镜和角度分辨光电子能谱等领域提供互补的专业知识。毕业的HQP受雇于老牌公司担任工程师，他们自己是领先的初创企业，或者是教师。

The discovery of the graphene field effect transistor over a decade ago precipitated a renaissance in 2D materials: 2-dimensional sheets of tightly bound atoms stacked together. The layered materials include insulators, semiconductors, semimetals and metals. The long-term goal of my research program is to understand and exploit the unique properties of 2D materials for electron devices. Over the past 5 years my research group has: developed graphene oxide acoustic devices now being commercialized by start-up ORA Graphene Audio, achieved record pH sensing precision with graphene transistors, achieved a world record for quantum Hall effect in low mobility material, and we were among the first to observe 2D charge transport in black phosphorus. Building on our expertise with graphene and black phosphorus, my research program has three main themes: new 2D materials, new 2D transistor fabrication techniques, and new 2D transistor structures. In the first theme, we will characterize the bandstructure and charge transport characteristics of SnSe, a polar analogue of black phosphorus with record thermoelectric figure of merit. We will also exfoliate ultra-thin layers of Sb, a heavier pnictogen than black phosphorus, where there is a competition between spin-orbit coupling and quantum confinement leading to a predicted semimetal to semiconductor transition as the atomic layer limit is approached. In parallel, we will develop a flip-chip method that will allow us to fabricate transistors with environmentally sensitive 2D materials such as black phosphorus in a completely inert environment, minimizing the deleterious effects of oxidation. Lastly, we will develop new transistor structures in black phosphorus. This includes quantum point contacts to understand spin polarized current flow in black phosphorus, and dual-gate transistors that apply the Stark effect for bandgap tuning during transistor operation.Highly qualified personnel (HQP) will be trained using state of the art research infrastructure including semiconductor device characterization tools. A glove box with optical microscopy, atomic force microscopy, and exfoliation tools enables the fabrication of 2D material transistors. HQP have access to shared use facilities such as the Laboratoire de Microfabrication at École Polytechnique with electron beam lithography and Raman spectroscopy tools. My group is a regular user of the National High Magnetic Field Laboratory (NHMFL) in Tallahassee for access to the world's highest static magnetic fields. We have active ongoing collaborations with researchers around the world who provide complementary expertise in areas such as molecular beam epitaxy, scanning tunelling microscopy, transmission electron microscopy, and angle resolved photoemission spectroscopy. Graduated HQP are employed as engineers at established firms, are leading start-ups of their own, or are teachers.