2D Materials Engineering for Electron Devices

十多年前石墨烯场效应晶体管的发现促进了2D材料的复兴：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利用电子设备的2D材料的独特性能。在过去的5年里，我的研究小组开发了氧化石墨烯声学器件，现在正在由初创公司ORA Graphene Audio商业化，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，我们是第一批观察到黑磷中二维电荷传输的人。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，我们将描述SnSe的能带结构和电荷输运特性，SnSe是黑磷的极性类似物，具有创纪录的热电优值。我们还将剥离超薄层的锑，一个重氮族元素比黑磷，那里有一个自旋轨道耦合和量子限制之间的竞争，导致预测的半金属到半导体过渡的原子层极限接近。与此同时，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使用对环境敏感的2D材料（如黑磷）制造晶体管，从而最大限度地减少氧化的有害影响。最后，我们将开发新的黑磷晶体管结构。这包括量子点接触，以了解黑磷中的自旋极化电流，以及在晶体管操作期间应用斯塔克效应进行带隙调谐的双栅极晶体管。高素质的人员（HQP）将接受培训，使用最先进的研究基础设施，包括半导体器件表征工具。手套箱与光学显微镜，原子力显微镜和剥离工具，使2D材料晶体管的制造。HQP可以使用共享设施，如École Polytechnique的微加工实验室，其中包括电子束光刻和拉曼光谱工具。我的团队经常使用塔拉哈西的国家强磁场实验室（NHMFL），以获得世界上最高的静磁场。我们与世界各地的研究人员积极合作，他们在分子束外延、扫描隧道显微镜、透射电子显微镜和角分辨光电子能谱等领域提供互补的专业知识。毕业的HQP被聘为成熟公司的工程师，领导自己的初创企业，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.