Dislocation contrast in cathodoluminescence and electron-beam induced current maps on GaN(0 0 0 1). (11th September 2017)

• Record Type: Journal Article
• Authors: Sabelfeld, Karl K; Kaganer, Vladimir M; Pfüller, Carsten; Brandt, Oliver
• Is Part Of: Journal of physics. Volume 50:Number 40(2017)
• Publication Date: 2017-09-11
• Subjects: cathodoluminescence -- EBIC -- dislocation -- GaN; Physics -- Periodicals; 530
• DOI: 10.1088/1361-6463/aa85c8
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: We theoretically analyze the contrast observed at the outcrop of a threading dislocation at the GaN(0 0 0 1) surface in cathodoluminescence and electron-beam induced current maps. We consider exciton diffusion and recombination including finite recombination velocities both at the planar surface and at the dislocation. Formulating the reciprocity theorem for this general case enables us to provide a rigorous analytical solution of this diffusion-recombination problem. The results of the calculations are applied to an experimental example to determine both the exciton diffusion length and the recombination strength of threading dislocations in a free-standing GaN layer with a dislocation density of 6 × 10 5 c m − 2 .