Bandgap engineering for 2D materials for device applications

固态设备是所有现代电子产品的支柱。器件特性本质上取决于半导体特性和质量的质量。在过去的几十年里，硅、砷化镓、锗等无机半导体材料一直被用于高性能器件。随着设备尺寸的缩小，人们一直在寻找更新的设备材料。此外，还有更灵活的电子产品，以及生物可穿戴设备与电子产品的集成，这需要使用不同的材料。二维材料是独一无二的，并提供了几个可以用于设备应用的优势。这些材料在单分子层内的原子之间有共价键，但在两个单分子层之间有范德华力。这使得它们比传统的无机半导体(如硅、锗等)更容易实现单层厚度。二维材料家族包括半导体、电介质和半金属。二维半导体具有很高的迁移率，并且其中许多是随着单层数的增加而可调的带隙。这提供了另一个优势，即将它们用作LED等发光应用和电子设备的直接带隙材料，因为它们具有高的本征迁移率，从而导致快速设备。在该方案中，将使用脉冲激光沉积在高真空环境下生长二维材料。这将产生高质量的大面积材料，用于设备应用。此外，还将原位生长包括两种二维材料的异质结，用于开发光学谐振器。这些材料的特征是了解它们的材料、电学和光学属性，这将为优化生长和开发高性能光学和电子设备提供反馈。这些2D材料器件可以应用于从光电子学到生物传感的各种应用。这里我们将重点关注两个应用，即开发可用于生物传感应用的异质结构晶体管和可用于柔性电子设备的光电子器件。这些材料的开发将有助于加强纳米材料和纳米设备领域，这是经济多样化的重要领域。艾伯塔省和加拿大都将从这一材料和设备领域的发展中受益。电子和光电设备拥有巨大的市场，对于包括显示器、电子产品和生物传感器在内的柔性电子产品的应用，这一市场预计到2027年将增长到约420亿美元，比2020年增长7.4%。因此，这是一个重要的重点领域和一项新技术；包括材料生长和设备开发将是艾伯塔省和加拿大纳米技术部门非常重要的一步。

Solid state devices are the backbone of all the modern electronics. The device properties inherently depend upon the quality of the semiconductor properties and quality. Inorganic semiconductor materials like silicon, GaAs, Ge to name a few have been used for high performance devices for the past several decades. As the device dimensions have shrunk there has been a quest for newer materials for devices. Also, there are more flexible electronics and integration of bio wearables with electronics which require different materials to be used. 2-dimensional materials are unique and offer several advantages which can be exploited for device applications. These materials have covalent bonding between the atoms within a monolayer but Van der Waal forces between two monolayers. This makes them achievable in monolayer thickness far more easily as compared to the traditional inorganic semiconductors like silicon, germanium etc. The family of 2-dimensional materials includes semiconductors, dielectrics, and semi-metals. The 2- dimensional semiconductors offer high mobility and many of them are tunable bandgap with the number of monolayers. This offers another the advantage of using them as direct bandgap materials for light emitting applications like LED's and for electronic devices as they have high intrinsic mobility which leads to fast speed devices. In this proposal, 2-dimensional materials will be grown under high vacuum environment using pulsed laser deposition. This will produce high quality large area material which will be used for device applications. In addition, heterostructures which include two types of 2-dimensional materials will be grown in-situ, which will be used to develop optical resonators. These materials will be characterised to understand their material, electrical and optical properties which will provide feedback to optimize the growth and develop high-performance optical and electronic devices. These 2D material devices can be applied for a variety of applications ranging from optoelectronics to biosensing. We will focus on two applications here, namely, developing heterostructure transistors that can be used for biosensing applications and optoelectronic devices that can be used for flexible electronics. The development of these materials will help strengthen the area of nanomaterials and nanodevices, which are important areas for economic diversification. Both Alberta and Canada will benefit from the development of this area of materials and devices. Electronic and optoelectronic devices have huge market and for applications in flexible electronics including displays, electronics and biosensors, this market is expected to grow to ~$42B by 2027 with a growth of 7.4% from 2020. Thus, this is an important thrust area and a novel technology; including material growth and device development will be a very important step for the nanotechnology sector both in Alberta and for Canada.