Nucleation and growth of silicon nitride nanoneedles using microwave plasma heating

We report on needlelike silicon nitride nanowires grown on silicon using am monia microwave plasma heating. Scanning electron microscope reveals that t he nanoneedles are either straight, slightly bent, or kinked with sharp tip s. Transmission electron microscope shows that the sizes of the nanowire ti ps are less than 5 nm and the structures are well crystallized. X-ray diffr action on the surface of the as-deposited structures indicates that both al pha -silicon nitride and beta -silicon nitride exist. Catalyst particle spl itting and merging explain observed structure derivation and bending. A vap or-liquid-solid model is employed to explain nucleation and growth mechanis m.