Analytical Electron Microscopy of Silicon Nitride Nanostructures Synthesized from the Vapour Phase [Microscopía electrónica analítica de nanoestructuras de nitruro de silicio sintetizadas a partir de la fase de vapor]

Abstract

In the present study, the size, morphology and composition of the silicon nitride powder (Si3N4) were studied by analytical electron microscopy techniques. Samples synthesized at 300 °C by precipitation from the vapor phase reaction of SiCl4 and NH3 were analyzed using Field Emission Scanning Electron Microscopy (SEM) acquiring images with secondary electrons (SE) and back-scattered electrons (BSE). Their crystalline phases obtained by heat treatment in an argon stream at 1500 ºC were analyzed using Transmission Electron Microscopy (TEM) combining electron diffraction and energy dispersive X-ray spectroscopy (EDS). The results show different morphologies and a wide size distribution of the silicon nitride powder depending on the content of N, O and Si. The high degree of agglomeration shows particles in the micrometer range, however, the individual size of the particles is in the nanometer-scale.