Scalable High Performance 1D Metal-Insulator-Graphene Diodes for High Frequency Applications Based on 2D Materials from Chemical Vapor Deposition

在该项目中，将开发基于2D材料的新型高性能1D金属-绝缘体-石墨烯（Metal-Insulator-Graphene，简称MIM）二极管和相应的可扩展工艺。金属、绝缘体和石墨烯层将横向布置。石墨烯-绝缘体结将在石墨烯的1D边缘处形成。这种1D二极管几何结构的主要优点之一是与现有技术的基于薄膜技术的二极管（即，传统的垂直金属-绝缘体-金属（MIM）二极管）相比电容减小。此外，在这样的1D几何结构中的电流密度高得多。为了进一步提高二极管的性能，将单层石墨烯封装在两层六方氮化硼（hBN）层之间，以提高二极管的性能。由于与石墨烯类似的六方结构的性质以及与石墨烯的弱货车范德华相互作用，hBN层保留了石墨烯的高迁移率。hBN还适当地将石墨烯与环境隔离，这对于器件和电路的长期稳定性至关重要。为了实现1D二极管的大规模工艺，将利用化学气相沉积（CVD）来生产2D材料石墨烯和hBN。这些2D材料的质量决定了二极管的高性能。因此，2D材料CVD生长的科学问题需要深入研究，然后根据器件性能解决。为了展示这种二极管的应用潜力，该项目还将展示用于高频应用的大规模高性能一维二极管，例如射频功率检测或光电检测。

Within this project a novel high performance 1D metal-insulator-graphene (MIG) diode based on 2D materials and a corresponding scalable process will be developed. The metal, insulator, and graphene layers will be arranged laterally. The graphene-insulator junction will be formed at the 1D edge of the graphene. One of the main advantages of this 1D diode geometry is the reduced capacitance compared to the state-of-the-art for thin-film technology based diodes, i.e. conventional vertical metal-insulator-metal (MIM) diodes. Besides, the current density in such a 1D geometry is much higher. These two advantages ensure that the 1D diode is a very promising candidate for future terahertz applications because of the low derived resistance-capacitance (RC) product.To further improve the performance of the diode, the monolayer graphene will be encapsulated between two hexagonal boron nitride (hBN) layers. The hBN layer preserves the high mobility of graphene due to nature of the similar hexagonal structure as graphene and the weak van der Waals interaction with graphene. hBN also properly isolates graphene from the environment, which is critical for the long term stability of the devices and circuits.To realize the large scale process for the 1D diode, chemical vapor deposition (CVD) will be utilized to produce both of the 2D materials, graphene and hBN. The quality of these 2D materials determines the delivery of the high performance of the diode. Therefore the scientific problems for CVD growth of 2D materials will need to be intensively investigated and afterwards solved with alignment to the device performance. To show the application potential of such diode, the large scale high performance 1D diodes for high frequency application, such as radiofrequency power detection or photo detection, will also be demonstrated within this project.