Crystallized hydroxyapatite coatings deposited by PLD with targets of different densities

We successfully achieved the poly-crystallized coatings of bio-active hydroxyapatite on titanium plates. We used several ceramic HAp targets sintered at a temperature of 500°C, 700°C, 900°C and 1100°C, and irradiation by KrF excimer laser at a fluence of about 4J/cm2. The depositions were performed under 1Torr H2O atmosphere at room temperature. In this condition, a poly-crystallized HAp layer was formed only using a target sintered at 900°C. We estimated the charged fragments from these targets by a simple ion-probe collection and found that the energy distribution of charged fragments depended on the densities of the targets.