Lee, Seung Min Yum, Jung Hwan Yoon, Seonno Larsen, Eric S. Lee, Woo Chul Kim, Seong Keun Shervin, Shahab Wang, Weijie Ryou, Jae-Hyun Bielawski, Christopher W. Oh, Jungwoo 2024-01-20T00:00:52Z 2024-01-20T00:00:52Z 2021-09-03 2017-12-06 1944-8244 https://pubs.kist.re.kr/handle/201004/121932 We have grown a single-crystal beryllium oxide (BeO) thin film on a gallium nitride (GaN) substrate by atomic-layer deposition (ALD) for the first time. BeO has a higher thermal conductivity, bandgap energy, and dielectric constant than SiO2. As an electrical insulator, diamond is the only material on earth whose thermal conductivity exceeds that of BeO. Despite these advantages, there is no chemical-vapor-deposition technique for BeO-thin-film deposition, and thus, it is not used in nanoscale-semiconductor-device processing. In this study, the BeO thin films grown on a GaN substrate with a single crystal showed excellent interface and thermal stability. Transmission electron microscopy showed clear diffraction patterns, and the Raman shifts associated with soft phonon modes verified the high thermal conductivity. The X-ray scan confirmed the out-of-plane single-crystal growth direction and the in-plane, 6-fold, symmetrical wurtzite structure. Single-crystalline BeO was grown on GaN despite the large lattice mismatch, which suggested a model that accommodated the strain of hexagonal-on-hexagonal epitaxy with 5/6 and 6/7 domain matching. BeO has a good dielectric constant and good thermal conductivity, bandgap energy, and single-crystal characteristics, so it is suitable for the gate dielectric of power semiconductor devices. The capacitance-voltage (C-V) results of BeO on a GaN-metal-oxide semiconductor exhibited low frequency dispersion, hysteresis, and interface-defect density. English American Chemical Society ELECTRON-MOBILITY TRANSISTORS ALGAN/GAN HEMTS THERMAL-CONDUCTIVITY GATE LEAKAGE MOS-HEMT PERFORMANCE DENSITY OXIDE SI PASSIVATION Atomic-Layer Deposition of Single-Crystalline BeO Epitaxially Grown on GaN Substrates Article 10.1021/acsami.7b13487 1 ACS Applied Materials & Interfaces, v.9, no.48, pp.41973 - 41979 ACS Applied Materials & Interfaces 9 48 41973 41979 scie scopus 000417669300036 2-s2.0-85037746362 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Science & Technology - Other Topics Materials Science Article ELECTRON-MOBILITY TRANSISTORS ALGAN/GAN HEMTS THERMAL-CONDUCTIVITY GATE LEAKAGE MOS-HEMT PERFORMANCE DENSITY OXIDE SI PASSIVATION beryllium oxide gallium nitride atomic-layer deposition domain-matching epitaxy power devices