Dresden 2011 – scientific programme

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HL: Fachverband Halbleiterphysik

HL 41: Nitrides: InGaN

HL 41.3: Talk

Tuesday, March 15, 2011, 14:45–15:00, POT 51

InGaN quantum wells in quaternary AlInGaN barriers — •Julian Mack, Clemens Wächter, Alexander Meyer, Michael Jetter, and Peter Michler — Institut für Halbleiteroptik und Funktionelle Grenzflächen and Research Center SCoPE, University of Stuttgart, Pfaffenwaldring 57, D-70569 Stuttgart, Germany

The luminescence efficiency of green emitting InGaN quantum wells grown in between c-plane GaN barriers suffers from strong electrical fields. To overcome this problem we have grown InGaN quantum wells embedded in quaternary AlInGaN barriers by metal-organic vapor phase epitaxy. By using a growth sequence for the barriers with pulsed metal-organic supply we enhanced the photoluminescence efficiencies of these structures. The amount of material was varied, resulting in AlInGaN barriers with constant thickness and indium contents between 1% and 20%. We have analyzed the material properties by x-ray diffraction (XRD) and ensemble photoluminescence (PL) measurements. The observed XRD-spectra and the PL-intensity show the high quality of the deposited material. The Pl spectra of the InGaN quantum wells shift from 2.60 eV to 2.75 eV with decreasing indium content of the barrier. This shift can be attributed to a reduction of the internal electric fields at the heterointerface between InGaN and AlInGaN and the associated quantum confined stark effect (QCSE).