Measurement of Piezoelectric Properties of Pulsed Laser Deposited Hydroxyapatite Thin Films on Platinum or Titanium Substrate

In order to measure the piezoelectric properties of the Hydroxyapatite (HAp) films, we have fabricated Cu/HAp/Ti or Cu/HAp/Pt structure. At first, a 1.5 m thick HAp was deposited on a Ti or Pt substrate using the KrF Pulsed Laser Deposition (PLD) method. After the HAp deposition, the HAp film was crystallized by post-annealing in nitrogen gas atmosphere and cooled slowly in an electric furnace. Then, a Cu top electrode sheet was attached on HAp film. Finally, one end of the Cu/HAp/Ti or Cu/HAp/Pt structure was clamped to compose a vibrating cantilever beam. Piezoelectric coefficients were estimated by output voltage responses of HAp films measured by a operational amplifier circuit when the Cu/HAp/Ti or Cu/HAp/Pt beam was excited by a mini-shaker at the first natural frequency of the beam. The results showed the piezoelectricity of the artificially synthesized HAp films.