Influence of Pulse Width on CdS Film Prepared by YAG Laser Ablation

CdS films were deposited on glass substrates using two kinds of YAG lasers: one with a long pulse width of τ=100 µs and one with a short pulse width of τ=15 ns. Scanning electron microscopy observation and X-ray diffraction patterns showed that the film formed by the long pulse laser with a low energy density has a smooth surface and highly oriented texture. Resistivity is distributed in a wide range: 100-2000 Ωcm and 10-100 Ωcm for the films formed by long and short pulse lasers, respectively. Measurement of optical transmission spectra suggests the existence of an impurity level in the low resistivity film. Streak image of the plume obtained using an image converter camera showed that the average velocity of ablated luminous particles is about 5×104 cm/s for long pulse laser ablation and (3-9)×105 cm/s for the short one.