GaN-on-AlN platform for Complementary Logic in III-Nitrides

After revolutionizing the lighting industry with the white LED, wide-bandgap III-nitride semiconductors 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 GaN-on-AlN 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.