GaN nanostructures by hot dense and extremely non-equilibrium plasma and their characterizations

Abstract

High temperature, high density, and extremely non-equilibrium argon plasma produced in modified dense plasma focus device is used to generate ions from pellet of gallium nitride (GaN) fixed on the top of anode and deposited on glass, quartz, and silicon substrates. Atomic force microscope (AFM) study on glass substrate shows nearly spherical nanostructures. AFM and scanning electron microscope studies on quartz substrate show nearly spherical nanostructures and on silicon substrate show comet-like nanostructures. Energy-dispersive X-ray scattering does not show any peak of impurities and there is deficiency of nitrogen in GaN. X-ray diffraction spectra show amorphous nature on glass substrate, whereas nanocrystalline GaN is observed on quartz and silicon substrates. Photoluminescence spectra show peaks of band edge emission, red luminescence, blue luminescence, and UV luminescence bands. Raman study on silicon substrate show peaks of E2 (high), A1, and E1 modes.