The grown-in defects in Czochralski Si crystals were well known to have a void-type shape. Recently, it was reported that in N-doped Si crystals the grown-in defects were formed in some different shapes. The density of these defects in N-doped Si crystals was remarkably higher than that of Czochralski Si crystals. The morphology of grown-in defects and the morphological change of grown-in defects upon annealing N-doped Si crystals was studied using transmission electron microscopy. This showed that there was one kind of nitride precipitate in N-doped Si crystals. The growth of whisker-like defects was identified in N-doped Si crystals after H annealing. Nitrogen and O were detected from these whisker-like defects. The whisker-like defects contain both a distorted diamond structure and an amorphous structure that was clarified by the high-resolution transmission electron microscopic images.

The Morphology of Grown-In Defects in Nitrogen-Doped Silicon Crystals. H.Fujimori, H.Fujisawa, Y.Hirano, T.Okabe: Journal of Crystal Growth Volumes, 2002, 237-239, 338-44