Elaboration of dense ceramics and glass ceramics piezoelectric coatings by selective laser treatments

In this research, the behavior of barium titanate powders under selective laser irradiation is investigated. The purpose is to determine suitable conditions to sinter the powders and form dense BaTiO3 thin components usable in hybrid circuits. Preliminary tests were performed on powders compacts in order to characterize the response of the powders according to the laser scan conditions with two different lasers (10 W Yb-laser or 20W Nd-YVO4). In order to investigate a specimen configuration similar to microelectronic components the laser treatment of a BaTiO3 coating deposited by spraying on a platinum covered alumina substrate has been performed. The microstructures obtained after laser treatment of powder compacts is evaluated by XRD, SEM and EDS. A high laser beam power is required to obtain a consolidation of the powder grains and the use of a high scan speed avoids the melting. The scanning conditions also influence the crystallographic state of final BaTiO3. Laser scanning conditions were founded in order to obtain a dense and homogeneous BaTiO3 coating exhibiting good bonding with the substrate.