Femtosecond pulse crystallization of thin amorphous hydrogenated films on glass substrates using near ultraviolet laser radiation

Femtosecond laser treatments (second harmonic of Ti-sapphire laser, $\lambda\approx400$ nm wavelength, $<30$ fs pulse duration) were applied for crystallization of thin hydrogenated amorphous silicon films on glass substrates. The concentration of atomic hydrogen in the films was varied from $10$ to $\approx35\%$. The energy densities (laser fluences) for crystallization of the films with thicknesses from $20$ to $130$ nm were found. Assumedly, non-thermal processes (plasma annealing) take place in phase transition caused ultra-fast pulses. The developed approach can be used for creation of polycrystalline silicon films on non-refractory substrates.