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To enhance biocompatibility, osteogenesis, and osseointegration, we coated titanium implants, by krypton fluoride (KrF) pulsed laser deposition, with a thin film of fluoridated hydroxyapatite (FHA). Coating was confirmed by scanning electron microscopy (SEM) and scanning probe microscopy (SPM), while physicochemical properties were evaluated by attenuated reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Calcium deposition, osteocalcin production, and expression of osteoblast genes were significantly higher in rat bone marrow mesenchymal stem cells seeded on FHA-coated titanium than in cells seeded on uncoated titanium. Implantation into rat femurs also showed that the FHA-coated material had superior osteoinductive and osseointegration activity in comparison with that of traditional implants, as assessed by microcomputed tomography and histology. Thus, titanium coated with FHA holds promise as a dental implant material.

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We have grown a-axis oriented YBa2Cu3O7−y (YBCO) films on LaSrGaO4 (LSGO) (100) substrates with (100) oriented seed layer of PrBa2Cu3O7−x (PBCO) using a pulsed laser deposition technique. PBCO films on LSGO (100) deposited even at ∼800 °C exhibits the a-axis orientation. In this temperature range, PBCO films on SrTiO3 (100) substrate exhibits the c-axis orientation. The YBCO film with a-axis orientation was grown on this PBCO(100) layer at a wide range of 650–800 °C. The YBCO films on PBCO free substrates have, on the other hand, c-axis orientation normal to the surface of the LSGO (100). We found that the preferred orientations of YBCO thin films can be controlled by the presence of PBCO films on LSGO substrate. For the a-axis orientated YBCO films, the resistance perpendicular to the c axis is 1/2 of that parallel to the c axis, suggesting the preferred orientation of c axis along the surface. The zero resistance superconducting transition temperature (Tc) of the films on the LSGO (100) and PBCO (100)/LSGO (100) substrates are 88.0 and 89.0 K, respectively.

In this study, we prepared a uniaxially oriented oxide on a flexible polymer substrate. We first grew [100] oriented SrTiO3 (STO) on a MgO(100) substrate. After bonding the STO film to a poly(ethylene naphthalete) (PEN) sheet with a photoresist, we etched the MgO substrate with a phosphoric acid solution to transfer the oxide film to the PEN sheet. The thin (300 nm) STO films did not crack after release, even after bending the sheet around a rod with a 1 cm radius, while the thicker (800 nm) films did. Ultimately, this process could be adapted to prepare a flexible epitaxial oxide.

As-grown YBa2Cu3O7−y (YBCO) thin films of 70 nm thickness have been prepared on LaSrGaO4(001), (100), and (110) single-crystal substrates at 700 °C using ArF laser ablation deposition. The c-axis oriented thin films with smooth surface morphology are obtained on LaSrGaO4 (001) and (100) substrates. The zero resistance temperatures (Tc) of the films on the (001) and (100) substrates are 90.0 K, and 88.1 K, respectively. On the (110) substrate, (110) YBCO planes grow epitaxially. The resistance perpendicular to the c axis in this film is 1/3 of that parallel to the c axis, showing Tc⊥=85.9 K and Tc∥=84.4 K, respectively. These results suggest that a LaSrGaO4 substrate having a low dielectric constant is an excellent substrate for the epitaxial growth and device application of high-Tc YBa2Cu3O7−y superconducting films.

In the current studies, we deposited ultra-thin hydroxyapatite films on a pure titanium substrate by pulsed laser deposition, and we examined the effects of these surfaces on rat bone marrow (RBM) cells. This method allowed deposition of 500-, 2,000-, and 5,000-A-thick hydroxyapatite films. X-ray diffraction showed that the amorphous films recrystallized to a hydroxyapatite crystal structure after annealing. The proliferation of RBM cells was unaffected by the hydroxyapatite films, but osteocalsin and alkaline phosphatase mRNA and protein levels were elevated in cells grown on 2,000- and 5,000-A-thick films. These results indicate that ultra-thin hydroxyapatite films generated by pulsed laser deposition are better at promoting osteogenesis than pure titanium surfaces.

The bilayer deposition technique supplies quick and long-term fixation of implants to bone, because the B-HA film dissolves to aid osteoconduction right immediately after implantation and the HA thin film maintains osteoconduction without dissolution. Neither of the thin-film fractures easily compared with thick coatings.