Quantitative investigation of indium distribution in InN wetting layers and dots grown by metalorganic chemical vapor deposition

Abstract

InN dots grown by metalorganic chemical vapor deposition were analyzed using atom probe tomography and transmission electron microscopy. A dot was found to be composed of pure InN at the core with a sharp interface with its underlying GaN layer and a more diffuse interface with its top GaN cap layer. Both techniques revealed the hexagonal truncated pyramid shape of the dots. APT has been used in the analysis of the wetting layers formed between the quantum dots. The fractional coverage appeared to saturate at longer growth times, with the highest fraction of monolayer coverage found to be 0.6.