FuSe-TG: Electro-Thermal Co-Design Center for Ultra-Wide Bandgap Semiconductor Devices

Nontechnical Description: Ultra-wide bandgap semiconductor devices based on beta-phase gallium oxide offer the potential to achieve higher power switching performance/efficiency and lower manufacturing cost than today's wide bandgap electronic devices. However, one of the most critical challenges to the commercialization of this ultra-wide bandgap device technology is to overcome adverse thermal effects that impact the device performance and reliability. This project develops a university-industry-national laboratory partnership that ultimately leads to the formation of an ultra-wide bandgap device electro-thermal co-design center. The outcomes of this work facilitate the development a new class of kV-range gallium oxide power switching devices that will support existing and new applications that require high peak power, harsh environment operation, and low system size/weight; especially given the national shortage of semiconductor chips. The educational goal of this project is to create a multi-disciplinary educational model for university students and industry researchers that combines device and thermal engineering concepts, keeping abreast of current trends in these fields. This new interdisciplinary education model supports training a globally engaged workforce that realizes breakthroughs in the semiconductor device industry. Technical Description: The research goal of this project is to create a gallium oxide device architecture with minimized thermal resistance realized by a bonding pad over active area approach and diamond-incorporated flip-chip integration. The principal investigators demonstrate the use of an electro-thermal co-design technique to realize a thermally aware device architecture that allows the full exploitation of the benefits offered by the ultra-wide bandgap semiconductor. A co-design modeling framework is developed that links energy conversion and electronic/thermal transport within ultra-wide bandgap electronics. This modeling framework helps identify the electrical and thermal design trade-offs at the material, device, and system levels. Novel laser-based pump-probe methods and optical/electrical thermography techniques are used to provide feedback to validate modeling results and improve the material synthesis and device integration processes. Since the proposed device integration method is material agnostic, it can be applied to existing wide bandgap and other emerging ultra-wide bandgap (e.g., aluminum gallium nitride) device technologies that are known to suffer from overheating and thermal instability. 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.