Date(s) - 24 Feb 2020
10:00 AM - 11:30 AM
3043 ECpE Building Addition
Title: Ultra-wide Bandgap Semiconductors: New Opportunities Toward Energy Efficient Electronics
Abstract: The forthcoming revolution in information technology, including electric vehicles, Internet of Things, 5G and beyond communications, and automated systems would require a massive network of electronics. As conventional semiconductors, such as silicon, fail to fulfill the functioning and efficiency requirements, there are tremendous opportunities for more advanced materials and electronics with the capability of high operation frequency, high power density, wide spectrum sensing and flexibility. Ultra-wide bandgap semiconductors, including III-Nitrides and the emerging diamond and β-Ga2O3 material systems, have superior intrinsic material properties that are suitable for high power, high frequency electronic devices, as well as energy-efficient optoelectronic device applications. They could enable significant improvements in the energy efficiency compared to the incumbent technologies based on Si, and trim the size, weight and cost of consumer electronics. Their heterogeneous integration with functioning materials could further enable transformational applications, and lead to new device concepts and system architectures. In this talk, I will present my recent work on the emerging β-Ga2O3 material system and discuss its exciting materials and devices developments. In particular, I will focus on the realization of modulation-doped heterostructures, and discuss the extraction of several critical materials parameters, including the effective mass, electron saturation velocity and breakdown strength, based on the transport measurements of the two-dimensional electron gas (2DEG). I will then discuss novel device architectures to fully exploit the exceptional materials properties for high power density and fast switching capabilities.
Bio: Dr. Yuewei Zhang is currently a postdoctoral researcher working with Professor Jim Speck at UC Santa Barbara. He received his PhD degree in electrical and computer engineering from the Ohio State University in 2018, and his BS degree in physics from Peking University (China) in 2013. Dr. Zhang’s research interests are centered around the materials science and device engineering of wide bandgap semiconductors – especially Ga2O3 and GaN, including their high quality epitaxy, micro/ nano-scale devices and heterointegrations for energy efficient electronic and optoelectronic device applications.
Seminar Host: Degang Chen