High-quality ScAlN/GaN heterostructures were grown by molecular beam epitaxy (MBE), and transport properties were investigated in detail by temperature-dependent Hall-effect measurements. Due to the high density of the 2DEG, a research group led by Assistant Professor Takuya Maeda of the School of Engineering at the University of Tokyo pointed out the necessity of considering the increase in the electron effective mass caused by the nonparabolicity of the conduction band, and quantitatively discussed the impacts of polar optical phonon, acoustic deformation, and interface roughness scattering. It is found that the dominant scattering mechanism of the two-dimensional electron gas (2DEG) in the heterostructures is the interface roughness scattering. These findings are expected to contribute to the development of high-frequency, high-power GaN high electron mobility transistors (HEMTs), and to advance next-generation high-frequency communication technologies.
Papers
Conference: The 15th International Conference on Nitride Semiconductors (ICNS 15)
Title: Scattering Mechanism of 2DEG in ScAlN/GaN Heterostructures Grown by Plasma-Assisted Molecular Beam Epitaxy
Authors: Kouei Kubota, Yusuke Wakamoto, Takahiko Kawahara, Shigeki Yoshida, Kozo Makiyama, Ken Nakata, Ryosho Nakane, Takuya Maeda*
Colossal Magnetoresistive Switching Induced by d0 Ferromagnetism of MgO in a Semiconductor Nanochannel Device with Ferromagnetic Fe/MgO Electrodes
