No abstract

Use of electron beam induced current (EBIC) method in combination of the multifractal analysis for investigation of GaN epitaxial layers with different degree of order of mosaic structure has revealed basic difference in distribution of extended defects with intense nonradiative recombination and small diffusion length of about 0.1 mm. The diffusion length of the layers with well ordered mosaic structure was determined to be 1.5-2 times longer than that of the layers with less-ordered mosaic structure. The difference between the extended defect distributions well correlates with peculiarities of carrier transfer in these layers.Introduction It is well known that the mosaic structure typical for hexagonal III nitride materials leads to an inhomogeneous distribution of electrical and optical properties. This inhomogeneous distribution can be easy revealed by different mapping techniques but the comparative quantitative analyses of images obtained on different samples by the conventional methods is rather difficult. As it was shown in Ref. [1], an application of multifractal parameterization (MP) approach allows such analyses and quantitative comparison of different structures. In particular, using the MP approach for the treatment of atomic force microscopy data allowed to characterize quantitatively such properties of mosaic structure of GaN as the degree of order (the local symmetry disruption) and the self-organization degree (the Renyi dimension) and to reveal the interconnection between these parameters and the majority charge carrier mobility. In the present work the results of MP application for the treatment of GaN EBIC maps are reported.

No abstract