Phase Stabilized MOCVD Growth of β‐Ga₂O₃ Using SiO_x on c‐Plane Sapphire and AlN/Sapphire Template

Abstract

The growth of monoclinic phase-pure gallium oxide (β-Ga 2 O 3 ) layers by metalorganic chemical vapor deposition on c-plane sapphire and aluminum nitride (AlN) templates using silicon-oxygen bonding (SiO x ) as a phase stabilizer is reported. The β-Ga 2 O 3 layers are grown using triethylgallium, oxygen, and silane for gallium, oxygen, and silicon precursors, respectively, at 700 °C, with and without silane flow in the process. The samples grown on sapphire with SiO x phase stabilization show a notable change from samples without phase stabilization in the roughness and resistivity, from 16.2 to 4.2 nm and from 85.82 to 135.64 Ω cm, respectively. X-ray diffraction reveals a pure-monoclinic phase, and Raman spatial mapping exhibits higher tensile strain in the films in the presence of SiO x . The β-Ga 2 O 3 layers grown on an AlN template, using the same processes as for sapphire, show an excellent epitaxial relationship between β-Ga 2 O 3 and AlN and have a significant change in β-Ga 2 O 3 surface morphology.