الفهرس 
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Abstract
Thin film samples of Ti (213nm) deposited onto Si (100) substrate are studied using Laser Induced Plasma Spectroscopy (LIPS). Depth profiling was carried out on samples as deposited and after thermal annealing (10-5 mbar, 450.°C) for 1,3 and 6 hours to investigate the metal semiconductor interface dynamics before and after annealing. The LIPS experiments were performed using three different experimental setups. A Nd:YAG laser (1064nm, 6 ns, 7mJ/pulse), an Excimer laser (308 nm, 24 ns, 7 mJ/pulse) and a femtosecond laser (795 nm, 130 fs and 200 u.l/pulse) were employed in the experiments. The Average Ablation Rate (AAR) was found to differ significantly according to the used laser system: 142 nrnlpulse in case of the Nd:Y AG laser, 61 nrnlpulse for the excimer laser and 13 nrnlpulse for the femtosecond laser. Also the crater diameter was measured for the samples in each case. The thin film was examined using X-Ray Diffraction (XRD) and Atomic Force Microscope (AFM) while the formation of the interface was studied using Rutherford Back Scattering (RBS) before and after thermal annealing. To verify the depth profiling results a theoretical model is proposed that gave good agreement with the experimental results. It has been concluded that although a very small AAR was achieved (13 nmlpulse) using femtosecond laser, there wasn’t any difference between the depth profiles of the annealed and none annealed samples. This shows that the beam profile is a decisive parameter in performing depth profile using LIPS, and it is not possible to use the Gaussian beam profile in making depth profiling.Key Words: Laser induced Plasma, Thin Films, Depth profiling.