Collaborative Research: High-frequency, High-power Amplifier Based on Distributed Coupling of GaN HEMTs Through a SiC Substrate-integrated Waveguide

【摘要】高频、高功率源是利用电磁频谱的关键。该项目可能使下一代毫米波电子产品具有前所未有的带宽和功率，同时最大限度地减少其尺寸、重量、功耗、成本和故障率。设计、集成和制造110 GHz以上大功率源的方法，以及这些器件在电磁耦合、毫米波性能和热计量方面的特性，可以在未来用于进一步提高单片集成功率放大器的带宽和功率，不仅覆盖整个毫米波频率范围，还包括未被广泛利用的太赫兹频率。衬底集成波导（SIW）平台可以将其他电子元件，如高质量滤波器和天线，单片集成在一个芯片上，这在传统集成电路中是很困难的。该项目通过促进无处不在的无线通信、智能人机界面和物联网（IoT），直接影响未来的工作。据估计，无线通信目前覆盖了大约60%的地球表面，这使得只有大约一半的世界人口可以访问互联网。6G无线通信由毫米波源实现，其体积小、重量轻、功率大、成本低、可靠，可以将覆盖范围扩展到地球表面的100%，使每个人都可以访问互联网。基于超低损耗SiC SIW，采用一种新型行波放大器（TWA）将高电子迁移率晶体管（hemt）以分布式方式组合，克服了传统单片毫米波集成电路的功率组合和阻抗匹配难题。共面波导上的准横向电磁波与SIW上的横向电磁波的分布同步耦合是一种新技术，SIW与晶体管的单片集成也是一种新技术。这种方法利用在SiC上外延生长的高质量GaN，通过单片集成实现高频、高功率性能。这种单片集成可以在分布式几何结构中实现前所未有的精度和场强，这是传统的分块加工部件或印刷电路板上的混合集成无法实现的。这为高频电路的功率和效率性能提供了一条途径，否则是无法实现的。作为概念验证测试工具，twa在D频段（110-170 GHz）的输出功率为1 w，并进行了设计、制造和表征。如果成功，类似的方法可以用于在更高的频率下产生更高的功率，或者在其他半导体技术中实现。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

AbstractNontechnicalHigh-frequency, high-power sources are critical to exploiting the electromagnetic spectrum. The project may enable the next generation of millimeter-wave electronics with unprecedented bandwidth and power, while minimizing their size, weight, power consumption, cost, and failure rate. The methodologies developed to design, integrate, and fabricate high-power sources above 110 GHz, and to characterize these devices in terms of electromagnetic coupling, millimeter-wave performance, and thermal metrology can be used in the future to further improve the bandwidth and power of monolithically integrated power amplifiers to cover not only the entire millimeter-wave frequency range, but also terahertz frequencies that are not widely exploited. The substrate-integrated waveguide (SIW) platform may enable other electronic components such as high-quality filters and antennas to be monolithically integrated on a single chip, which has been difficult with conventional integrated circuits. The project directly impacts Future of Work by facilitating ubiquitous wireless communications, smart man-machine interfaces, and Internet of Things (IoT). It is estimated that wireless communications currently cover approximately 60% of the Earth surface, making Internet accessible to only about half of the world's population. 6G wireless communications enabled by millimeter-wave sources that are small, light, powerful, low cost, and reliable can extend the coverage to 100% of the Earth surface, making Internet accessible to everyone.TechnicalBased on an ultra-low-loss SiC SIW, a novel traveling-wave amplifier (TWA) is used to combine high-electron-mobility transistors (HEMTs) in a distributed manner for overcoming the power combining and impedance matching challenges of conventional monolithic millimeter-wave integrated circuits. Distributed and synchronous coupling between a quasi-transverse-electromagnetic wave on a grounded coplanar waveguide and a transverse-electric wave on an SIW is new, as is monolithic integration of SIW with transistors. This approach takes advantage of high-quality GaN grown epitaxially on SiC to achieve high-frequency, high-power performance through monolithic integration. This monolithic integration allows unprecedented precision and field strength in a distributed geometry, which is impossible to realize with conventional split-block machined parts or hybrid integration on a printed circuit board. This provides a path to high-frequency circuits with power and efficiency performance that is not otherwise attainable. As a proof-of-concept test vehicle, TWAs capable of 1-W output power at the D band (110-170 GHz) are designed, fabricated, and characterized. If successful, similar approaches can be used to generate higher powers at higher frequencies, or be implemented in other semiconductor technologies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.