Alkali doping of graphene and van der Waals heterostructures for 2D materials device engineering

该项目的目标是开发用碱原子对石墨烯和货车德瓦尔斯异质结构进行受控掺杂的方法。石墨烯是典型的2D材料，由碳原子层组成。不同二维材料的组装，称为货车德瓦尔斯异质结构，是传统化合物半导体异质结构的类似物，是激光二极管、高迁移率晶体管和其他实现信息和通信技术的器件的核心。与化合物半导体不同，取代杂质原子掺杂以控制电荷密度的传统方法不能应用于控制石墨烯以及货车和德瓦尔斯异质结构中的电荷密度。通过表面吸附和嵌入碱金属原子的掺杂提供了控制电子掺杂的可能性。碱金属原子的低电子亲和势导致吸附或嵌入时的近单位电离。经常用于超高真空条件下的表面科学实验，这项工作的目标是在手套箱环境中将碱掺杂扩展到由石墨烯和货车德瓦尔斯异质结构组成的有源电子器件。该项目是纳米电子学专家T。Szkopek（麦吉尔大学）和表面科学家A。Grüneis（科隆大学），汇集互补的专业知识和基础设施，以推进基于2D材料的电子设备碱掺杂的最新技术。这一基本工作的潜在技术应用范围从热电，电子，化学传感器。加拿大的预期收益包括通过国际合作获得更广泛的专业知识和基础设施，加强对高素质人员的实践培训，并发展二维材料开发前沿的应用知识。这两个因素都有助于加拿大在2D材料应用开发方面的领导地位。值得注意的是，Szkopek实验室开发的知识产权已经导致加拿大第一个使用石墨烯的消费电子产品的商业化。

The goal of this project is to develop methods for the controlled doping of graphene and van der Waals heterostructures with alkali atoms. Graphene is the prototypical 2D material, consisting of an atomic sheet of carbon. Assemblies of different 2D materials, known as van der Waals heterostructures, are analogues of traditional compound semiconductor heterostructures that are at the core of laser diodes, high mobility transistors, and other devices that enable information and communication technologies. Unlike compound semiconductors, traditional methods of substitutional impurity atom doping to control charge density cannot be applied to control charge density in graphene and van and der Waals heterostructures. Doping by surface adsorption and intercalation with alkali atoms offers the possibility of controlled electron doping. The low electron affinity of alkali atoms leads to near unity ionization upon adsorption or intercalation. Frequently used in surface science experiments in ultra-high vacuum conditions, the goal of this work is to extend alkali doping to active electronic devices composed of graphene and van der Waals heterstructures in a glove box environment. This project is an international, transdisciplinary collaboration between nanoelectronics expert Prof. T. Szkopek (McGill University) and surface scientist Prof. A. Grüneis (University of Cologne), bringing together complementary expertise and infrastructure to advance the state-of-the-art in alkali doping of electronic devices based on 2D materials. Potential technological applications of this fundamental work range from thermoelectrics, to electronics, to chemical sensors. Expected benefits to Canada include the strengthening of hands-on training of highly qualified personnel by access to broader expertise and infrastructure through international collaboration and the development of applied knowledge at the forefront of 2D materials development. Both factors contribute to Canada's leadership in application development of 2D materials. Notably, intellectual property developed in Szkopek's laboratory has already led to Canadian commercialization of the first consumer electronics produce making use of graphene.