Structure Transition Mechanism of Single-Crystalline Silicon, g-C3N4, and Diamond Nanocone Arrays Synthesized by Plasma Sputtering Reaction Deposition

Single-crystalline silicon, g-C3N4, and diamond nanocone arrays were synthesized on nickel-covered silicon (100) substrates by a novel method of plasma sputtering reaction deposition. The experimental results show that the morphologies, structures, and composition of the as-grown nanocones strongly depend on the ratios of the inlet mixed gases. The silicon, g-C3N4, and diamond nanocone arrays could be grown at the CH4/(N-2 + H-2) ratios of about 1/20-1/10, 1/150-1/60, and 0, respectively. The analyses of the optical emission spectra from the discharged plasma indicate that the inlet methane controls the growth of the nanocones by suppressing the Frsputtering effect to adjust the amounts of the silicon, carbon, and nitrogen atoms attaining the substrate, which determines the composition, structures, and crystallinity of the grown nanocones.