Synthesis and characterization of dandelion-shaped SiCN rods

Assited by Co as catalyst, an interesting structure, dandelion-shaped SiCN rods, was synthesized using microwave plasma chemical vapor deposition method with gas mixtures of CH₄, H₂ and N₂ as precursors and Si chips inserted in the sample holder at symmetrical positions around the specimen as additional Si sources. Scanning electron microscopy shows each rod has not only a column about 0.4~0.8 mum in diameter and about 10~20 mum in length, but also a ~2 mum sized ball-like tip, from which nanowiskers of 0.3 mum long with 20~30 nm in diameter were formed. The samples are atomic-level hybrids composed of Si, C and N atoms. Two strong peaks (3.25 and 2.84 eV) were observed from photoluminescence spectroscopy at room temperature, indicating the dandelion-shaped SiCN rods have potential application in optoelectronic devices.