Fabrication of III-V nano- and microtubes using MOVPE grown materials

We fabricated III-V nano- and microtubes with a diameter in the range of 140 nm to 6 mu m using strained heterostructures with high quality interfaces, which were grown by metal-organic vapor-phase epitaxy (MOVPE). Investigations of the two-layer system BGaAs/InGaAs which forms tubes by selective etching of an AlAs sacrificial layer are presented. Calculations of the tube diameter and the internal strain using continuum strain theory dependent on the layer thickness and composition were made. We also fabricated AlGaAs/InGaAs microtubes containing a GaAs quantum well (QW) in different sections of the AlGaAs barrier material and studied the optical properties of this embedded QW using photo- and cathodoluminescence spectroscopy at different temperatures. By measuring the luminescence peak-shift of the QW caused by uniaxially stress, we were able to verify our calculations of the radial profile of the strain within the microtube wall. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.