Physica status solidi. C, Conferences and critical reviews/Physica status solidi. C, Current topics in solid state physics · 2005 · 10 citations · 0 references
EngineeringMaterials EngineeringMaterials ScienceElectronic MaterialsSemiconductor DevicesSemiconductor MaterialsDefects In Electronic MaterialsDislocations In SemiconductorsLight-emitting DiodesOptical Properties Of SemiconductorsSemiconductor DefectsSemiconductor SurfacesElectroluminescenceExternal Quantum EfficiencyGallium NitrideLight-emitting DevicesLight-emitting MaterialsOptical PropertiesPhotoluminescence SpectroscopySurface Optical Properties
The results on surface control of light-emitting structures (LES) based on MQW InGaN/GaN grown by MOCVD on (0001) sapphire substrates have been presented. For these purposes, the treatment of atomic-force-microscopy data by multifractal analyses has been applied. It was shown, that multifractal parameter (the degree of order of mosaic structure, Δ) reflects the peculiarities of the extended defect system (EDS), including mosaic structure and high density of dislocations, and correlates with the volume structural, electrical and optical properties of LES. Depending on Δ, EDS relaxes with formation of either the domain dilatation boundaries or numerous domain dislocation boundaries and these structural peculiarities influence essentially the shape of photo-and electroluminescence spectra, delayed spectra and the values of external quantum efficency. The surface control using Δ can be applied to optimize the properties of LES and the process of their creation. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)