Lanthanoid-doped gallium nitride (GaN) semiconductors have attracted attention because of their high intensity luminescence and sharp room-temperature (RT) optical linewidth. GaN surfaces can be chemically functionalized and nanometer-sized particles are available, opening the door to lifescience applications such as bioimaging and biosensing. Neodymium (Nd)-doped GaN is of strong interest due to its strong near infrared luminescence at 0.9~1.1 µm which is suitable for optical imaging in biological tissues. To realize bioimaging/sensing using Nd-doped GaN nanoparticles, the small ensemble of Nd ions has to be optically detected at RT with high contrast. This paper reports photoluminescence of Nd ions implanted into submicron regions of GaN epilayer and their luminescence properties at RT. The Nd implanted square regions with the side of 250 nm were optically detected. The minimum size which was successfully fabricated and optically detected was 150 nm in this study, which supports further investigations into fluorescent nanoparticles for bioimaging applications. In the presentation, PL spectra, PL excitation spectra, saturation behavior, and luminescent transition lifetime at RT will be discusse29th Annual Meeting of MRS-