Fractal analysis of InGaN self-assemble quantum dots grown by MOCVD

Recently, it has been shown that nitride nanostructures can be self-assembled using growth interruption during the metal-organic chemical vapor deposition (MOCVD) growth. In this work, strain-induced InGaN-GaN self-assembled quantum dot (SAQD) samples were grown by MOCVD. A fractal dimension processing has been applied to characterize the surface roughness of uncapped InGaN-GaN SAQDs. The fractal dimension D can be used to describe the influence of different annealed conditions on surface characterization. Fractal analysis reveals the surface roughness of nanostructure surfaces is decreased after the annealing process. It can be seen that a smoother surface was obtained under an annealing temperature at 800 °C, and it implies that the surface roughness of this case is minimum in all tests. The results of this paper also described a mathematical modeling method for the observation of the fractal dimension in semiconductor nanostructure films.