Crystallization, fluoridation and some properties of apatite thin films prepared through rf-sputtering from CaO-P2O5 glasses.
Using calcium phosphate glass targets with the CaO/P2O5 molar ratios of 1.50-0.50, much lower than the stoichiometric value of 3.3 for hydroxyapatite, thin films of stoichiometric hydroxy-, nonstoichiometric oxyhydroxy- and Ca-deficient oxyhydroxy-apatites were prepared on alumina ceramic substrates by rf-sputtering followed by post-annealing. Based on the present results, a phase diagram for CaO-P2O5 at low temperatures in the ambience of air was depicted for thin films. The ambient H2O vapor had an influence on the phase diagram: Tricalcium phosphate was changed to apatite in the presence of H2O vapor. Dense fluorohydroxyapatite thin films were prepared by fluoridation of those apatite thin films at a low temperature such as 200 degrees C. In the present report, some functional properties of thin films thus prepared were also shown.
Yamashita
K
K
Division of Inorganic Materials, Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, Japan. yama-k@imde.tmd.ac.jp
Matsuda
M
M
Arashi
T
T
Umegaki
T
T
D000537:Aluminum Oxide; D001031:Apatites / Q000737:chemistry*; D017610:Calcium Compounds / Q000737:chemistry; D002130:Calcium Phosphates / Q000737:chemistry; D002516:Ceramics; D003460:Crystallization; D004553:Electric Conductivity; D005459:Fluorides / Q000737:chemistry; D005898:Glass / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D017553:Phosphorus Compounds / Q000737:chemistry; D013499:Surface Properties
D001031:Apatites; D017610:Calcium Compounds; D002130:Calcium Phosphates; D010087:Oxides; D017553:Phosphorus Compounds; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; C012500:phosphorus pentoxide; C485838:calcium phosphate, monobasic, anhydrous; C020243:calcium phosphate; C016538:lime; C485829:calcium phosphate, dibasic, anhydrous; D000537:Aluminum Oxide; D005459:Fluorides