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

该项目的目标是开发控制掺杂石墨烯和范德华异质结与碱原子的方法。石墨烯是典型的2D材料，由一层碳原子组成。不同2D材料的组件称为范德华异质结构，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设备的核心。与化合物半导体不同，传统的替代杂质原子掺杂来控制电荷密度的方法不能用于控制石墨烯和van和der Waals异质结中的电荷密度。通过表面吸附和与碱原子插层的掺杂提供了控制电子掺杂的可能性。碱原子的低电子亲和力导致了吸附或插层时的近单位电离。碱掺杂常用于超高真空条件下的表面科学实验，本工作的目标是将碱掺杂扩展到手套盒环境中由石墨烯和范德华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教授(麦吉尔大学)和表面科学家A.Grüneis教授(科隆大学)之间的国际跨学科合作，将互补的专业知识和基础设施结合在一起，推动基于2D材料的电子设备碱掺杂的最先进水平。这项基础工作的潜在技术应用范围从热电学、电子学到化学传感器。加拿大的预期收益包括通过国际合作获得更广泛的专门知识和基础设施，以及在2D材料开发的前沿发展应用知识，从而加强对高素质人员的实际培训。这两个因素都有助于加拿大在2D材料应用开发方面处于领先地位。值得注意的是，Szkopek实验室开发的知识产权已经导致加拿大首个使用石墨烯的消费电子产品商业化。

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.