After revolutionizing the lighting industry with the white LED, wide-bandgap III-nitride semiconductors like GaN are now pushing to replace conventional semiconductors such as Silicon in a wide range of high power and high frequency applications - such as radars, next-gen 5G/6G cellular base stations. Taking advantage of the intrinsic polarization physics of III-nitrides lets us generate 2D electron gases (2DEGs) at epitaxially-grown heterojunctions, which are used to make n-channel transistors in the form of commercially available high electron mobility transistors (GaN HEMTs). But the lack of a commensurate p-channel transistor has held back Si-CMOS-like efficient digital logic in III-nitrides electronics so far. This talk will present AlN-substrate platform as an alternative to current technologies and will motivate how its material properties gives it an advantage over the conventionally used GaN-substrate based III-nitride devices. Using novel growth techniques, high-density 2D electron gas (2DEG) and the long missing undoped 2D hole gas (2DHG) in III-nitrides have recently been discovered on this platform. These have enabled record performance n-channel AlN HEMTs and p-channel transistors, as well as insights into fundamental physics of III-nitrides. Combining them, AlN-substrate based devices provide the most promising platform for demonstrating and achieving efficient electronics via high-voltage complementary low-loss digital switches.
Reet Chaudhuri is a third year PhD student in Electrical Engineering under Prof. Debdeep Jena and Prof. Huili (Grace) Xing at Cornell University. He did his undergrad from the NIT Tiruchirapalli, followed by Master’s in Applied Physics at Cornell before joining the group in the summer of 2016. His research interests include the growth of group III-nitride heterostructures using Molecular Beam Epitaxy (MBE), and studying the fundamental physics of charge transport in these novel heterostructures for device applications.