New oxide crystal (La,Sr)(Al,Ta)O_3 as substrate for GaN epitaxy

摘要

A new candidate single crystal (La,Sr)(Al,Ta)O_3 (LSAT) as a substrate for GaN epitaxial growth was found. Mixed- perovskite (111) oriented crystals were successfully grown by conventional Czochralski method. Excellent lattice matching with gallium nitride makes this material specially promising. Determination of the lattice parameters and the phase identification obtained crystals by X-ray diffraction analysis was carried out. Thermal expansion, thermal conductivity and electrical conductivity were measured. GaN epitaxial layers have been grown on (111) LSAT substrate and the results are presented.