Shubnikov-de Haas oscillations of two-dimensional electron gases in AlYN/GaN and AlScN/GaN heterostructures

AlYN and AlScN have recently emerged as promising nitride materials that can be integrated with GaN to form two-dimensional electron gases (2DEGs) at heterojunctions. Electron transport properties in these heterostructures have been enhanced through careful design and optimization of epitaxial growth conditions. In this work, we report for the first time Shubnikov-de Haas (SdH) oscillations of 2DEGs in AlYN/GaN and AlScN/GaN heterostructures, grown by metal-organic chemical vapor deposition. SdH oscillations provide direct access to key 2DEG parameters at the Fermi level: (1) carrier density, (2) electron effective mass (m* ~ 0.24 me for AlYN/GaN and m* ~ 0.25 me for AlScN/GaN), and (3) quantum scattering time (~ 68 fs for AlYN/GaN and ~ 70 fs for AlScN/GaN). These measurements of fundamental transport properties provide critical insights for advancing emerging nitride semiconductors for future high-frequency and power electronics.