The effect of nitridation temperature on the structural, optical and electrical properties of GaN nanoparticles

Abstract

Synthesis of GaN nanoparticles (NPs) by a novel chemical co-precipitation method and the effect of nitridation temperature on the structural, optical and electrical properties have been reported. X-ray diffraction and high resolution transmission electron microscopy show the hexagonal wurtzite structure and highly crystalline nature of the GaN NPs. A strong blue luminescence was observed for all the GaN NPs at room temperature photoluminescence studies. Nevertheless, red and yellow luminescence were absent at the nitridation temperature of 1000 °C. The phonon frequency mode at the k-point of the Brillouin zone symmetry was observed at 271–273 cm⁻¹ for GaN NPs by micro-Raman spectroscopy, which is normally absent for bulk GaN. The carrier concentration and mobility of GaN NPs synthesized at higher temperature were calculated to be 1.36 × 10¹⁷ cm⁻³ and 433 cm² V⁻¹ s⁻¹, respectively, by the Raman line shape analysis of the longitudinal-optical-phonon–plasmon coupled mode.