Preparation of silicon nitride nanowires by using carbon nanotubes as the precursors

Solid silicon nitride nanowires were produced by using carbon nanotubes as precursors. The reaction was carried out in ammonia atmosphere, Si and SiO₂ were used as starting materials. The structure, phase composition, dielectric properties and oxidation resistance of the sample were investigated. The results showed that the sizes of the nanorods are 60-80 nm in diameter and up to several microns in length. In the products α-Si₃N₄ is the main component; due to nano-material´s quantum size effects, the FTIR spectra of the silicon nitride nanowires have blue shift phenomena; the sample shows good oxidation resistance in high temperature. The dielectric constants decrease with the increasing measuring frequency. The dielectric constants reduced from 9(10KHz) to 6.9(100MHz) at room temperature.