アモルファスSiO₂基板上へのc面配向ハイドロキシアパタイト成膜法の検討

抄録

We investigated a fabrication technique of c-plane oriented hydroxyapatite (HA) crystalline film on low cost amorphous SiO₂ substrates to apply the orientation-controlled HA crystal to disposal biochips. An experiment was conducted by the pulsed laser deposition (PLD) method. We showed that a high quality HA crystalline film was able to be grown by using a fluoroapatite (FA) buffer layer, which was self-oriented on amorphous SiO₂. A relationship between a FA film thickness and the HA quality was examined with an aim of minimizing a toxic risk of F to biomolecules, even if it was eluted from FA. It was found that the thickness of the FA film could be reduced to about 7.5 nm, at the same time, the crystallinity and a smoothness of HA were also excellent. A crystal growth model of FA on the amorphous SiO₂ was also studied. We considered that highly reactive F in a laser-ablated-plume substituted for O on the substrate surface, which became a migration trap, causing 3-dimensional island growth as FA crystal nuclei. This model consistently agreed with a series of experimental results.