Calcium phosphate coatings produced by ion beam sputtering/mixing deposition: their manufacture, structure and in vitro properties

Abstract

Ion beam sputtering/mixing deposition was used to produce dense and homogeneous calcium phosphate (Ca-P) coatings on titanium substrate. The mixing beam was either Ar+ or N+ ions. Scanning electron microscopy revealed that the deposited coatings had a uniform and dense structure. The calcium to phosphorous ratio of these coatings varied between 2.0 to 3.0. It was found that as-deposited coatings were amorphous. Results obtained from Fourier transform infrared spectroscopy (FTIR) showed the existence of the phosphate group in coatings but no distinct absorption band of the hydroxyl group was observed. Compared with Ca-P coatings produced by Ar+ beam mixing, Ca-P coatings produced by N+ beam mixing exhibited a higher dissolution rate in the physiological saline solution and caused a lower proliferation rate of osteoblast cells.