Characterization of GaN and GaN based structures by scanning electron microscopy methods

Results demonstrating possibilities of scanning electron microscopy methods for a characterization of GaN and GaN based light emitting structures are presented. Methods for correct excess carrier diffusion length measurementы in the structures with the small diffusion length are discussed. It is shown that the Electron Beam Induced Current (EBIC) method allows not only to measure the diffusion length in GaN films but in some cases to reconstruct also the lateral donor center distribution with a spatial resolution in the micrometer range. It is shown experimentally that in the structures with the small diffusion length the lateral resolution under extended defects revealing can be about 100 nm or even better. It is shown that channels of enhanced minority carrier transport across the active region of light emitting structures with InGaN/GaN quantum wells can be revealed by the EBIC.