Laser synthesis of ultrafine powders

Abstract Silicon and silicon carbide powders have been synthesized from silane and silane-ethylene (or acetylene) mixtures irradiated with a 50 W continuous wave (CW) tunable CO 2 laser. The irradiation geometry is the cross-flow configuration very similar to that described previously by Haggerty and coworkers at MIT. 1,2 Laser wavelength, cell pressure, gas flow rates and ratios are the varying factors. Collected powders have been physically characterized and chemically analyzed. Zirconium boride synthesis from sensitized dissociation of zirconium borhydride by sulfur hexafluoride excited with CO 2 laser (CW or TEA) is also presented.