Title: Toward Energy-efficient Electronics from Ultrawide-Bandgap Semiconductors: Materials, Devices, and Application
Abstract: The current technology is actively seeking advanced semiconductors to meet the growing demand for high-voltage electronics, such as electric vehicles, smart grid, internet-of-things, and data centers, where the existing silicon fails to perform due to its inherent material limits. Moreover, the rising awareness of climate change demands the future power electronics to be energy-efficient in enabling a green economy. Toward this goal, the wide-bandgap (WBG) semiconductors, with superior power handling capability, can be potential replacements of silicon for next generation energy-efficient electronics. However, unlike silicon, the WBG SiC and GaN suffer from high production cost and lack of high-quality bulk crystals that limit their expansion in power electronics market. Here, the new ultrawide-bandgap (UWBG) semiconductor, β-Ga2O3, can be a promising alternative to lead a paradigm shift in power electronics with multiple kilovolt range devices with reduced loss, lightweight designs, and lower production cost, that are inaccessible with SiC and GaN. However, the early stage of β-Ga2O3 translates to many existing challenges in device design, fabrication, material quality optimization, and extreme environment tolerance to reach rapid commercialization.
My research investigates the existing challenges of emerging ultrawide-bandgap semiconductors, including their device design, fabrication, and advanced electronic characterization, that aims to improve their high-voltage sustainability, reduce power loss, and increase extreme environment tolerance. In this presentation, I will demonstrate my research on development of high-voltage and low-loss β-Ga2O3 devices by integrating barrier engineering with oxidized noble metal contacts and electric field management with high permittivity and extreme permittivity dielectrics. Moreover, my work on advanced electronic characterization of β-Ga2O3 will be demonstrated to investigate its performance in extreme environment. Finally, I will discuss the strategy of developing high-power and radiation-tolerant β-Ga2O3 devices to enhance their efficiency and reliability in high-radiation space and defense systems.
Speaker Bio: Esmat Farzana is currently a Postdoctoral Researcher in Materials Department at the University of California, Santa Barbara, working with Prof. James Speck and Prof. Sriram Krishnamoorthy. She received her PhD in Electrical and Computer Engineering from The Ohio State University in 2019 working with Prof. Steven Ringel, and B.S. in Electrical Engineering from Bangladesh University of Engineering and Technology. Her research lies at the intersection of device development, advanced characterization, and extreme environment application with a focus on next-generation energy-efficient power electronics using wide-bandgap semiconductors, particularly β-Ga2O3 and III-nitrides. Her lead-author publications have been featured as Editor’s pick in IEEE Electron Device Letters, APL Materials, and Applied Physics Letters. She was also invited by American Institute of Physics (AIP) to be an editor for a book on β-Ga2O3 material and devices. She was selected a Rising Star in EECS in 2020.