Characterization of InGaN quantum dots grown by metalorganic chemical vapor deposition

Abstract

InGaN quantum dots were grown by metalorganic chemical vapor deposition and shown to exhibit a bimodal size distribution. Atom probe tomography was used to characterize the dots in conjunction with atomic force microscopy, photoluminescence, and x-ray diffraction. Small dots with low indium contents were found to coexist with larger, very high indium composition dots. Significant compositional fluctuations were observed in the small dot population. The dots showed abrupt interfaces with the surrounding GaN, verifying the ability to cap the dots without causing intermixing for even extremely high indium content dots.