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Metal‐polar InN quantum dots (QDs) are grown by metalorganic chemical vapor deposition at temperatures between 500 and 600 °C. Dot densities between 4 × 108 and 4 × 1010 cm−2 are observed. InN QDs exhibit room‐temperature photoluminescence (PL) with peak wavelengths from 1100 to >1550 nm. GaN cap layers grown on InN QDs have little effect on either peak PL wavelength or intensity, a step toward creating multilayer structures for InN QD devices. [ABSTRACT FROM AUTHOR]

Scanning tunneling electroluminescence (STL) microscopy is performed on a 3 nm‐thick InGaN/GaN quantum well (QW) with [In] = 0.23 such that the main light emission occurs in the green. The technique is used to map the radiative recombination properties at a scale of a few nanometers and correlate the local electroluminescence map with the surface topography simultaneously imaged by scanning tunneling microscopy. While the expected green emission is observed all over the sample, measurements performed on a 500 nm × 500 nm area around a 150 nm‐large and 2.5 nm‐deep hexagonal defect reveal intense emission peaks at higher energies close to the defect edges, features which are not visible in the macrophotoluminescence spectrum of the sample. Via a fitting of the local tunneling electroluminescence spectra, quantitative information on the fluctuations of the intensity, peak energy, width, and phonon replica intensity of the different spectral contributions is obtained, which provides information on carrier localization in the QW. This procedure also indicates that the carrier diffusion length on the probed area of the QW is shorter than 50 nm. [ABSTRACT FROM AUTHOR]