Near-field microscopy of waveguide architectures of InGaN/GaN diode lasers
S. Friede1, J.W. Tomm1, S. Kühn1, V. Hoffmann2, H. Wenzel2 and M. Weyers2
Published in:
Semicond. Sci. Technol., vol. 31, no. 11, pp. 115015 (2016).
Abstract:
Waveguide (WG) architectures of 420 nm emitting InGaN/GaN diode lasers are analyzed by photoluminescence and photocurrent spectroscopy using a nearfield scanning optical microscope that scans along their front facets. The components of the ‘optical active cavity’, quantum wells, WGs, and cladding layers are individually inspected with a spatial resolution of ~100 nm. Separate analysis of the p- and n-sections of the WG was achieved, and reveals defect levels in the p-part. Moreover, it is demonstrated that the homogeneity of the n-WG section directly affects the quantum wells that are grown on top of this layer. Substantially increased carrier capture efficiencies into InGaN/GaN-WGs compared to GaN-WGs are demonstrated.
1 Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Str. 2A, 12489 Berlin, Germany
2 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin, Germany
Keywords:
nearfield scanning optical microscopy, diode laser, InGaN/GaN.
Copyright © 2016 IOP Publishing Ltd. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the 2016 IOP Publishing Ltd.
Full version in pdf-format.