Relationship Between Impact Velocity of Al2O3 Particles and Deposition Efficiency in Aerosol Deposition Method

Aerosol deposition method (ADM) is a technique to form dense films by impacting solid particles to a substrate at room temperature. To improve the deposition efficiency in ADM, the relationship between the impact velocity of Al 2 O 3 particles and the deposition efficiency was investigated in this study. Relative difference in impact particle velocity was evaluated by the increment percentage of the substrate surface area after deposition (Δ S ). It is thought that the increase of Δ S means the increase of the impact particle velocity. When Δ S was lower than 10 %, the deposition efficiency increased from 0.082 to 0.104 % as Δ S increased from 3.46 to 9.25 %. Increasing impact particle velocity could promote the bonding between the particles themselves. On the other hand, when Δ S was higher than 10 %, the erosion of the film was observed and the deposition efficiency decreased to about 0.02 % as Δ S increased to about 40 %. SEM observation revealed that cracks parallel to the film surface were propagated. There is a possibility that this tendency of the deposition efficiency toward the impact particle velocity is common among the methods for forming ceramic films by impacting solid ceramic particles.