ECCS-EPSRC - Advanced III-N Devices and Circuit Architectures for mm-Wave Future-Generation Wireless Communications'

无处不在的高性能通信是我们社会的支柱，不仅在个人的日常生活中发挥着越来越重要的作用，而且在设备之间的通信背景中也同样重要（例如，用于移动性的车辆到基础设施，工业和制造业中的过程控制和监控，虚拟实境全环境的虚拟化等）。由此产生的必须处理和通信的数据爆炸需要非凡的带宽和网络无处不在，这反过来又要求支持高性能、高能效和低成本的电子产品。EPSRC-NSF的这一提案旨在实现最关键的链路--无线功率放大器的飞跃，这对于实现无处不在、高速、透明的移动的通信的愿景至关重要。功率放大器是任何通信系统中最关键的元件之一，因为它们决定了系统的整体效率。基于GaN的HEMT对于高性能功率放大器特别有前途，但是当前基于GaN的系统由于多种因素的组合而遭受有限的频率覆盖、效率和线性度，这些因素包括器件设计（例如，场板的使用有效地将操作限制到30 GHz及以下）和材料问题（例如，深能级陷阱）。自加热意味着增益和效率随着输出功率以及频率迅速降低。我们在这个计划中利用GaN基晶体管设计和新型电路拓扑结构的变革性进展，通过协同设计大幅提高通信系统关键无线元件的效率，带宽，线性度和成本。该技术基于极化工程渐变沟道GaN HEMT，与传统HEMT相比，该技术在线性度方面有了实质性的改善。通过结合对其底层器件物理（包括陷阱态和热管理）的深入研究，我们通过优化器件设计和制造，解决了在不断增加的频率（即Ka波段高达40 GHz）下降低GaN性能的主要影响。我们将设计基于新的连续模式类的谐波端接放大器，使设计人员能够为所需的效率、线性度和输出功率特性提供更广泛的阻抗选择。该项目汇集了圣母大学、布里斯托大学和谢菲尔德大学的世界领先专家，与英国和美国的支持行业合作，完成了两国从基板种植者、器件/芯片制造到电路设计师的整个供应链。有针对性的毫米波通信技术预计将成为新兴应用的下一个前沿，在推动英国、美国和全球所有地区繁荣的升级议程中发挥关键作用。例如，预计到2035年，5G将为英国价值13.2万亿美元的商品和服务提供新的产业。

Ubiquitous, high-performance communication is the backbone of our society, and promises to play an increasing role not only in individual's daily lives, but just as importantly in the background with communication among devices (e.g. vehicle-to-infrastructure for mobility, process control and monitoring in industrial and manufacturing, virtualization of full environments for the metaverse, among others). The resulting explosion in data that must be processed and communicated requires extraordinary bandwidth and network ubiquity, which in turn demands supporting electronics that is high performance, power efficient, and low cost. This EPSRC - NSF proposal targets a great leap forward in the most critical link, the wireless power amplifier, that is essential to realizing a vision of ubiquitous, high-speed, transparent mobile communication. Power amplifiers are among the most critical elements in any communication system as they dictates the overall efficiency of the system. GaN-based HEMTs are especially promising for high-performance power amplifiers, but current GaN-based systems suffer from limited frequency coverage, efficiency and linearity due to a combination of factors, including device design e.g. use of field plates effectively limits operation to 30 GHz and below, and materials issues e.g. deep level traps, self-heating means that gain and efficiency degrade rapidly both with output power as well as frequency. We leverage in this programme transformative advances in both GaN-based transistor design and novel circuit topologies to dramatically improve the efficiency, bandwidth, linearity, and cost of the key wireless elements of a communication system, through co-design. The technology is based on polarization-engineeered graded channel GaN HEMTs that show a substantial improvement in linearity in comparison to conventional HEMTs. By combining with thorough investigation of their underlying device physics including trap states and thermal management, we address major effects that degrade the performance of GaN at increasing frequencies (i.e. Ka band up to 40 GHz) by optimizing device design and fabrication. We will design harmonically terminated amplifiers based on our new class of contiguous modes, that allow designers wider choice of impedances for desired characteristics of efficiency, linearity and output power. The project brings together world leading experts in the Universities of Notre Dame, Bristol and Sheffield, working alongside supporting industry in UK and US, that completes the entire supply chain from substrate growers, device/chip fabrication to circuit designer in both countries. The targeted enabling millimetre-wave communication technology is expected to be the next frontier in emerging applications that play a critical role in the levelling up agenda to drive prosperity in all regions of the UK, the US and worldwide. For example 5G is expected to underpin new industries worth $13.2T in goods and services in the UK alone by 2035.