Calcium phosphate formation on nanocrystalline ZrO2 thin film prepared by using a zirconium naphthenate.

To investigate the calcium phosphate forming ability of ZrO2 thin film, we prepared ZrO2/Si structure by a chemical solution deposition with a zirconium naphthenate as a starting material. Precursor sol was spin-coated onto the cleaned Si substrate and prefired at 500 °C for 10 min in air, followed by final annealing at 800 °C for 30 min in air. Surface morphology and surface roughness of the annealed layer were characterized by field emission-scanning electron microscope and atomic force microscope. After soaking for 5 days in a simulated body fluid, formation of the calcium phosphate on nanocrystalline ZrO2 layer annealed at 800 °C was observed by energy dispersive X-ray spectrometer. Fourier transform infrared spectroscopy revealed that carbonate was substituted into the calcium phosphate.