Grain growth in heavily implanted LPCVD polysilicon layers during annealing

Polycrystalline silicon layers were heavily implanted (doses >5x1014 atoms cm-2) with either phosphorus or arsenic ions. Direct heating in a transmission electron microscope revealed that a rapid increase in the average grain size of the layers occurs within the first few minutes of an anneal above 7000C. The larger grains form by the crystallization of the amorphous implanted film produced by the implantation. The crystallization mechanism observed favours lateral growth of grains in particular orientations and produces the noted <110> texture. (author)