Laser Synthesis of Low‐Agglomerated Submicrometer Silicon Nitride Powders from Chlorinated Silanes

The laser chemical vapor precipitation of Si 3 N 4 powder from mixtures of SiH 2 Cl 2 and NH 3 has been studied. The reactant gases were mixed at different heights with respect to the laser beam, thus preventing low‐temperature reactions and agglomeration of the produced particles. The morphology and the size of the particles formed are dependent on the injection height of NH 3 into the silicon reactant gas stream. Particle diameters are typically between 15 and 110 nm.