STUDY OF THE SURFACE CHARACTERISTICS OF MAGNETRON-SPUTTER CALCIUM-PHOSPHATE COATINGS

Plasma-sprayed hydroxylapatite coatings on metals such as titanium hav e been investigated for many years and have shown a good biocompatibil ity when implanted in bony tissues. Radiofrequency magnetron sputterin g was used as an alternative method to deposit thin films of hydroxyla patite on titanium substrates. X-ray diffraction demonstrated that the sputtered layer was crystalline with a preferred (001) crystallograph ic orientation with the C-axis perpendicular to the substrate surface. Scanning electron microscopy showed that the deposited films had a un iform and dense structure. The calcium phosphate ratio varied between 1.5 and 2.0, as determined by energy-dispersive X-ray analysis. The in vitro dissolution appeared to be determined by the degree of the coat ing's crystallinity. (C) 1994 John Wiley and Sons, Inc.