Berlin 2018 – wissenschaftliches Programm
HL 27.6: Vortrag
Mittwoch, 14. März 2018, 10:45–11:00, EW 203
Direct comparison of structural and optical properties of GaN fin LED microstructure with nonpolar sidewalls — •G. Schmidt1, P. Veit1, S. Petzold1, A. Dempewolf1, T. Hempel1, F. Bertram1, J. Hartmann2, H. Zhou2, F. Steib2, J. Ledig2, S. Fündling2, H.-H. Wehmann2, A. Waag2, and J. Christen1 — 1Institute of Experimental Physics, Otto-von-Guericke-University Magdeburg, Germany — 2Institute of Semiconductor Technology and Laboratory for Emerging Nanometrology, Technische Universität Braunschweig, Germany
We present structural and optical properties of an InGaN/GaN core-shell fin grown by metal organic vapor phase epitaxy (MOVPE) on GaN/sapphire template covered with a patterned SiOx-mask. The MOVPE process results in selective area growth of Si-doped GaN walls out of the mask openings oriented in m-direction. Enveloping the n-GaN core, an InGaN layer as active region was grown with stepwise decreasing temperature. The fin was completed by a GaN:Mg cover.
Using highly spatially resolved cathodoluminescence (CL) microscopy, we give a direct insight into the optical properties of the individual core-shell layers. The GaN:Si core exhibits drastically low CL intensity above the mask opening. The epitaxially lateral overgrown region over the mask shows high intensity of the GaN near band edge emission. The InGaN region exhibits the highest CL intensity between 370 nm and 450 nm wavelengths. As expected, a redshift of the InGaN emission towards the fin side wall surface was resolved indicating the continuous increase of In-incorporation.