Polycrystalline films were prepared via the laser crystallization of amorphous material at substrate temperatures of 300 or 673K. At these temperatures, polycrystalline films with grain sizes of 1.5 and 1.0μ were obtained by using laser fluences of 540 and 505mJ/cm2, respectively. An increase in the grain size resulted in a decrease in the spin density; due to a reduction in the grain-boundary volume. The increase in substrate temperature resulted in a pronounced decrease in the spin density; regardless of the laser energy density. Defects were passivated by exposing the polycrystalline films to monatomic H at 350C. This caused the spin density to decrease to a residual value of about 9 x 1016/cm3; regardless of the substrate temperature and laser fluence.

N.H.Nickel, G.B.Anderson, R.I.Johnson: Physical Review B, 1997, 56[19], 12065-8