Deosition And Characterization Of SiNanomaterial Produced By Pulsed Laser Ablation

Si-based nanograins are fabricated by pulsed laser ablation of monocrystaline Si target. Several measuremental techniques, including Scanning electronic microscopy SEM ) , Transmission electron microscopy ( TEM ), X-ray diffraction (XRD) Raman Scattering spectroscopy (Rarnan) and Photoluminescence (PL) , were used to analyze the morphology characteristic, light-emission and stabilization of the Si nanograins. The effects of several experimental parameters, such as gas pressure, laser energy, the different collecting methods on the growth of the Silicon nanograms are studied. We also discussed the mechanism of the growth and PL of the Si nanograins. The method to get high quality Si nanograins with controllable size and stable light-emission, such as using mask between the target and the substrate to eliminate the large droplets and using the silicon nitride as the passivating layer to process effective passivation, are also attempted. Laser annealing is also studied. The induced Ni indeed decreases the energ threshold for laser crystallization. The low energy crystallization makes the morphology of the Si material more uniform, avoiding the ununiformity of high energy laser annealing. The research show that the size and the stabilization of the Si nanograins have great effect to the PL, the passivating layer of SiNx can prevent the oxidation of the nanometer material, improve the stabilization of Si nanograins and the development of applying of the Si nanograins...