Mechanism of debris formation and deposition in excimer laser ablation Available to Purchase

Mechanism of formation and deposition of ultra-fine particles in excimer laser ablation of ceramic has been investigated on the basis of the measurement of plasma, shock wave propagation and debris particles. A disk-shaped cloud of ultra-fine particles with size of 10 nm appears at delay time of approximately 1 μs, and spreads radially along the target surface. The particle cloud begins to be driven to the target by a cooling wave produced by quick cooling of the hot plasma at around 10 μs. Then a part of the particles is deposited to the surface and another part of the particles is bounced to go up away. On the basis of the aforementioned mechanism, a simple formula was derived to estimate the amount of deposited particles where the growth rate of the particles is proportional to the dwell time of the decomposed particles within the blast wave, and inversely proportional to the volume of the blast wave sphere, and the fraction of the bouncing increases linearly with increasing ambient gas pressure. It is shown that the deposited ratio calculated from the model agrees well with the experimental results in various gas species and pressures.