Evaluation of beta-Ga2O3 for high power RF device applications

宽带隙(WBG)半导体提供了提供电子设备和系统的潜力，其先进的功率处理性能超过了硅。这源于它们在较高电压下工作的内在能力，这直接归因于它们较大的半导体带隙。尽管WBG技术GaN和SiC的发展取得了很大的进展，但具有更大禁带宽度的新型和新兴材料(所谓的超宽带隙半导体)提供了更大的潜在性能收益。最大限度地提高电子元件的高功率处理能力，对于解决我们目前面临的许多与能源和环境有关的挑战至关重要。例如，需要先进的高功率固态系统来实现智能电网，以实现未来的电力分配和电动汽车的高效电压转换。为了满足未来通信(如5G和6G移动通信)和雷达系统的性能要求，还需要运行在高频下的高功率系统。β-Ga2O3是一种超宽带隙(UWBG)材料，其带隙甚至比现有的WBG技术(GaN和SIC)更大，因此具有提供卓越的高功率性能的潜力。与其他WBG和UWBG材料相比，也可以使用类似于硅的工艺生产大面积β-Ga2O晶片，从而提供更大的大规模、成本效益制造的潜力。因此，β-Ga2O3目前处于独特的地位，可以满足不断发展的高功率电子系统带来的许多日益增长的要求和性能要求。β-Ga2O的固有材料特性也表明，它可能能够在高开关速度下工作，从而允许同时进行高功率和高频(GHz)操作。然而，到目前为止，还没有开展什么工作来探索这种射频(RF)、高功率应用的潜力和局限性。这项工作将研究β-Ga2O在生产高功率和高频工作的电子器件方面的潜力。我们将利用商业来源的β-Ga2O衬底进行可行性研究，以更好地了解它们的物理、化学和电子结构以及相关的电荷传输和电子器件生产潜力。利用以前在WBG和UWBG器件技术开发方面建立的专业知识，将建立用于制造场效应管等β-Ga2O器件的工艺协议。具有不同几何结构(强烈影响高功率和高频操作)的设备将被研究，以最大限度地了解设备操作和性能潜力。展望未来，这项工作的成果将用于与活跃在WBG和UWBG研究互补领域的国家学术团体和行业合作，确定英国境内正在进行的基于β-Ga2O的电子产品的研究战略。

Wide bandgap (WBG) semiconductors offer the potential to deliver electronic devices and systems with advanced power handling performance beyond that achievable in silicon. This stems from their intrinsic ability to operate at higher voltages as directly attributed to their larger semiconductor bandgap. Although excellent progress has been made in the development of WBG technologies GaN and SiC, new and emerging materials with even larger bandgap (so called ultra-wide bandgap semiconductors) offer even greater potential performance gains. Maximising such high-power handling capability in electronic components is essential to address many of the energy and environmental-related challenges that we currently face. For instance, advanced high-power solid-state systems will be required to enable smart power grids for future distribution of electricity and for efficient voltage conversion in electric vehicles. High power systems operating at high frequencies will also be required to meet the performance demands of future communication (e.g. 5G and 6G mobile comms) and radar systems. Beta-Ga2O3 is an ultra-wide bandgap (UWBG) material with a bandgap even larger than existing WBG technologies, GaN and SiC and hence offers the potential to deliver superior high power performance. Large area beta-Ga2O3 wafers may also be produced using similar processes to silicon, thus offering greater potential for large scale, cost effective manufacture compared to other WBG and UWBG materials. Beta-Ga2O3 is therefore currently in a unique position to meet many of the ever-increasing demands and performance requirements imposed by the continued development of high-power electronic systems. The intrinsic material properties of beta-Ga2O3 also suggest it may be able to operate at high switching speeds, thus allowing for simultaneous high power and high frequency (GHz) operation. Little work has as yet been undertaken however to explore the potential and limitations of beta-Ga2O3 for such radio frequency (RF), high power applications.This work will investigate the potential of beta-Ga2O3 for the production of electronic devices for both high power and high frequency operation. We will undertake a feasibility study utilising commercially sourced beta-Ga2O3 substrates to better understand their physical, chemical and electronic structure and the associated charge transport and electronic device production potential. Utilising previously established expertise in the development of WBG and UWBG device technologies, processing protocols for the creation of beta-Ga2O3 devices such as field effect transistors will be established. Devices with varying geometries (which strongly impact both high power and high frequency operation) will be investigated to maximise understanding of device operation and performance potential. Moving forward, the outputs of this work will be used to identify an ongoing research strategy for beta-Ga2O3 based electronics within the UK in partnership with national academic groups and industry active in complementary areas of WBG and UWBG research.