[5p-A301-1~19] 15.4 III-V-group nitride crystals

[5p-A301-15] Impact on electroluminescence of AlGaN-based deep-ultraviolet LED grown on macrosteps (part 2)

〇Yosuke Nagasawa¹, Michiko Kaneda¹, Akira Hirano¹, Masamichi Ipponmatsu¹, Yoshio Honda², Hiroshi Amano², Isamu Akasaki^3,4 (1.UV Craftory, 2.Nagoya Univ. - IMass, 3.Nagoya Univ. - ARC, 4.Meijo Univ.)

Keywords:AlGaN, LED, Deep ultraviolet

Impact on electroluminescence (EL) output of AlGaN-based deep-ultraviolet LEDs with MQWs grown on macrosteps were investigated. Both the surfaces of AlN and n-AlGaN grown on sapphire with 0.3^o and 1.0^o miscut angles relative to m-axis exhibited macrosteps in this work. The LEDs were fabricated simultaneously using the optimized growth recipes for 265, 285, and 300 nm. EL peak was redshifted for the 1.0 ^o miscut samples with denser macrosteps compared with those of 0.3 ^o miscut samples. EL spectral width for LEDs on 1.0 ^o miscut sapphire was increased in comparison with those of 0.3 ^o miscut sapphire.Fixing the sapphire miscut angle to 1.0 ^o and using an optimized growth recipe, a positive correlation was observed for 285nm-LEDs between the EL outputs and spectral widths. The similar phenomenon was also obtained for 265 nm-LEDs.These trends are considered to be caused by enhanced carrier localization adjacent to macrosteps.