We report the realization and the optical study of nitride photonic resonators dedicated to the blue and UV spectral range. Microdisks and photonic crystal (PC) cavities are investigated containing GaN/AlN quantum dots (QDs) embedded in an AlN waveguide. The PC cavities are fabricated through the conformal growth of nitrides on a patterned Si substrate, and present delocalized and confined cavity modes in their microphotoluminescence spectra, that are compared to simulations. A large quality factor of 1800 is reached for a modified L3 cavity. In the case of microdisks, which are fabricated through a classical top‐down approach, the series of whispering gallery modes (WGMs) with large quality factors (up to 7300) are observed and analysed.
Scanning electron micrograph and microphotoluminescence spectrum of a 2 µm AlN microdisk embedding GaN QDs; the WGMs appear as sharp peaks, with quality factors up to 5000.