Branching phenomena in Si3N4 whiskers

Abstract The branching phenomena in both α-Si 3 N 4 and β-Si 3 N 4 whiskers were investigated by transmission electron microscopy. Two mechanisms appear to be operating for the branching of α-Si 3 N 4 whiskers. One operates when the growth conditions are satisfied for more than two different growth directions, resulting in branched α-Si 3 N 4 whiskers. The second mechanism results in two whiskers, with different growth directions, growing together to form a branched bicrystalline α-Si 3 N 4 whisker; one acting as a branch of the other. Only the former branching mechanism was found to operate for β-Si 3 N 4 whiskers.