Indium incorporation in quaternary Inx Aly Ga1-x-y N for UVB-LEDs

Enslin, Johannes and Wernicke, Tim and Lobanova, Anna and Kusch, Gunnar and Spasevski, Lucia and Teke, Tolga and Belde, Bettina and Martin, Robert W. and Talalaev, Roman and Kneissl, Michael (2019) Indium incorporation in quaternary Inx Aly Ga1-x-y N for UVB-LEDs. Japanese Journal of Applied Physics, 58 (SC). SC1004. ISSN 0021-4922 (https://doi.org/10.7567/1347-4065/ab07a4)

[thumbnail of Enslin-etal-JJAP-2019-Indium-incorporation-in-quaternary]
Preview
Text. Filename: Enslin_etal_JJAP_2019_Indium_incorporation_in_quaternary.pdf
Final Published Version
License: Creative Commons Attribution 4.0 logo

Download (1MB)| Preview

Abstract

Consistent studies of the quaternary composition are rare as it is impossible to fully determine the quaternary composition by X-ray diffraction or deduce it from that of ternary alloys. In this paper we determined the quaternary composition by wavelength dispersive X-ray spectroscopy of Inx Aly layers grown by metal organic vapor phase epitaxy. Further insights explaining the peculiarities of Inx Aly Ga1-x-yN growth in a showerhead reactor were gained by simulations of the precursor decomposition, gas phase adduct formation and indium incorporation including desorption. The measurements and simulations agree very well showing that the indium incorporation in a range from 0% to 2% is limited by desorption which is enhanced by the compressive strain to the relaxed Al0.5Ga0.5N buffer layer as well as indium incorporation into AlN particles forming in the gas phase. Utilizing Inx Aly Ga1-x-yN layers containing 2% of indium for multiple quantum wells (MQWs), it was possible to show an almost five times higher photoluminescence intensity of InAlGaN MQWs in comparison to AlGaN MQWs.