Dose dependence of crystallization in implanted polycrystalline silicon films on SiO2

Crystallization of 1500 Å polycrystalline silicon films self-implanted at doses of 2×1015–6×1015 ions/cm2 is investigated. For doses of 2×1015–5×1015 ions/cm2, crystallization is due to the growth of crystallites which nucleate at a rate which decreases with increasing dose. Above 5×1015 ions/cm2, the nucleation rate is comparable to that of amorphous silicon, though a transient time is observed during which little or no nucleation occurs. The growth velocity does not appear to be dose dependent.