[20a-E310-1~10] 15.4 III-V-group nitride crystals

▼ [20a-E310-7] Study of luminescence properties of InGaN layers with wide-range lateral indium content profiling.

〇(P)Anna Kafar^1,2, Ryota Ishii¹, Szymon Stanczyk², Krzysztof Gibasiewicz², Szymon Grzanka^2,3, Tadeusz Suski², Piotr Perlin^2,3, Mitsuru Funato¹, Yoichi Kawakami¹ (1.Kyoto Univ., 2.IHPP PAS, 3.TopGaN Ltd.)

Keywords:gallium nitride, InGaN quantum wells, misorientation angle

A strong dependence of the indium incorporation on the misorientation angle gives a promising opportunity to create advanced measurement platforms or novel devices like superluminescent diodes with broadened emission spectra. Within this work, we employ micro photoluminescence studies (μPL), to examine how the large change of substrate misorientation angle modifies the emission properties of the InGaN quantum wells. After creating a 3D pattern on a bulk GaN substrate to form 40 μm areas with misorientation change in the range 0.7° - 4°, we grown a simple (Al,In)GaN structure with two InGaN quantum wells. The μPL mapping proved the achievement of indium content profiling, by showing a 35 nm range of emission wavelength from a single measurement area. However, apart from the emission wavelength variation, we also observe a linear correlation of the intensity of PL signal and the emission wavelength. The effect may be related to indium-content-dependent emission efficiency of InGaN QWs or the deviation form optimal growth conditions for high misorientation angles.