High-Temperature Ultra-Wide Bandgap Gallium Oxide Power Module

该NSF项目旨在解决目前限制高温、高密度电力电子技术发展的知识差距和挑战。高温电力电子产品可以通过减小冷却系统的尺寸和重量来提高运输系统的功率密度，并使功率转换器能够放置在环境温度较高的战略位置，例如靠近发动机或电机的位置。然而，较高的温度降低了现有电力电子元件的性能和可靠性。本项目旨在克服这些挑战，开发一种高温氧化镓功率模块。氧化镓是一种超宽带隙半导体，由于其优越的材料特性，有望成为高温电力电子的候选材料。该项目的智力优势包括了解半导体器件和封装的电热相互作用、高温封装封装剂和半导体器件栅电介质的解决方案以及热管理策略。该项目的更广泛影响包括对基于氧化镓的电力电子产品的可能性和挑战的洞察，以及高温封装方面的进步，这可能允许更高效、更高密度的电力运输和恶劣环境系统。该项目的其他更广泛的影响包括电力电子封装和超宽带隙半导体的本科生和研究生教育，以及多样性和包容性活动，如动手研讨会、实验室参观和为妇女和代表性不足的少数民族进行演示。极高的温度挑战了硅功率半导体的极限，并削弱了宽带隙器件的性能优势。尽管氧化镓具有优异的热稳定性，是一种很有前途的替代材料，但它的导热系数很低，这给封装和热管理系统带来了额外的挑战。另一个主要挑战是电力电子组件在高温条件下的可靠性。特别是，高温电源模块的一个关键限制是封装。该封装提供了基本的电气绝缘以及耐腐蚀性和保护。传统的聚合物包覆剂在高温下会迅速降解。这项工作旨在通过四个主要研究目标克服这些挑战：1)开发一个电热、器件-封装联合设计框架，使人们能够物理地了解器件-封装的相互依赖关系，并加速针对新兴功率半导体器件优化的功率模块的设计；2)评估和应用新的介质材料作为高温功率模块的封装剂，以及用作氧化镓功率器件的栅电介质和钝化；3)在器件和封装层面探索创新的散热策略，以提高基于镓的功率模块的热性能；4)演示高温氧化镓电源模块，并评估其电气、热和可靠性特性。从这项工作中获得的知识将阐明氧化镓功率器件的潜力，并使高温封装得到显著改进，从而促进电力运输和恶劣环境应用的重大进步。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This NSF project aims to address the knowledge gaps and challenges that are presently limiting the advancement of high-temperature, high-density power electronics. High-temperature power electronics can increase the power density of transportation systems by reducing the size and weight of the cooling system, and enabling the power converter to be placed in strategic locations with high ambient temperatures, such as in close proximity to the engine or motor. However, higher temperatures degrade the performance and reliability of present power electronics components. This project aims to overcome these challenges and develop a high-temperature gallium oxide power module. Gallium oxide is an ultra-wide-bandgap semiconductor that is emerging as a viable candidate for high-temperature power electronics due to its advantageous material properties. The intellectual merits of the project include understanding of semiconductor device and package electro-thermal interactions, solutions for high-temperature package encapsulants and semiconductor device gate dielectrics, and strategies for thermal management. The broader impacts of the project include insight into the possibilities and challenges for gallium-oxide-based power electronics, and advancements in high-temperature packaging, which could allow for more-efficient and higher-density electric transportation and harsh-environment systems. Other broader impacts of the project include undergraduate and graduate education on power electronics packaging and ultra-wide-bandgap semiconductors, and diversity and inclusion activities, such as hands-on workshops, laboratory tours, and demonstrations for women and underrepresented minorities.Extreme temperatures challenge the limits of silicon power semiconductors, and diminish the performance benefits of wide-bandgap devices. While gallium oxide is a promising alternative due to its superior thermal stability, it has low thermal conductivity, which creates additional challenges for the package and thermal management system. Another major challenge is the reliability of the power electronics package under high temperature conditions. In particular, a key limitation for high-temperature power modules is the encapsulation. The encapsulation provides essential electrical insulation, as well as corrosion resistance and protection. Traditional polymeric encapsulants degrade rapidly at elevated temperatures. This work aims to overcome these challenges through four main research goals: 1) to develop an electro-thermal, device-package co-design framework that will enable physical insights into the device-package interdependencies, and accelerate the design of power modules optimized for emerging power semiconductor devices; 2) to evaluate and apply new dielectric materials for use as the high-temperature power module encapsulant, and as the gate dielectric and passivation for the gallium oxide power device; 3) to explore innovative heat dissipation strategies at the device and package levels for improved thermal performance of gallium-oxide-based power modules; and 4) to demonstrate a high-temperature gallium oxide power module, and assess its electrical, thermal, and reliability characteristics. The knowledge gained from this work will illuminate the potential of gallium oxide power devices, and enable significant improvements in high-temperature packaging, which could facilitate major advancements in electric transportation and harsh environment applications.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.