[18p-146-1~8] New Process Technology of Nitride Semiconductors

[18p-146-5] Efficient photoluminescence from AlGaN-based singularity structures originating from step-bunching

〇Yoichi Kawakami¹, Minehiro Hayakawa¹, Mitsuru Funato¹ (1.Kyoto Univ.)

Keywords:AlGaN-based semiconductors, Step-bunching, Sigularity structures

When AlN is grown on slightly miscut substrate from polar plane, macro steps are created on the surface as a result of the accumulation of many molecular steps. We found that the photoluminescence lifetimes of AlGaN quantum wells (QWs) grown on such structures are increased comparing to those of conventional planar AlGaN QWs as a result of carrier localization to Ga-rich wire-shaped AlGaN localization centers created at macro steps. Therefore, it is probable that AlGaN-based singularity structures, which are promising for achieving higher luminescence efficiency, are naturally formed as evidenced by the suppression of nonradiative recombination rates.