We demonstrated room-temperature (RT) intense ultraviolet (UV) emission in the wavelength range of 315–370 nm from quaternary InxAlyGa1−x−yN alloys grown by metalorganic vapor-phase epitaxy. We found that the UV emission is considerably enhanced by the In-segregation effect upon introducing 2%–5% of In into AlGaN. The In incorporation in quaternary InxAlyGa1−x−yN is markedly enhanced with the increase of Al content when using a relatively high growth temperature (830–850 °C), resulting in efficient RT UV emission. Maximally efficient emission was obtained at around 330–360 nm from the fabricated quaternary InxAlyGa1−x−yN (x=2.0%–4.8%,y=12%–34%). The intensity of the 330 nm emission from quaternary In0.034Al0.12Ga0.85N was as strong as that of the 430 nm emission from In0.22Ga0.78N at RT. We clearly observed In segregation of submicron size from cathode luminescence images of quaternary InAlGaN films.

We demonstrated room-temperature (RT) intense ultraviolet (UV) emission with wavelength in the range of 300–340 nm from Inx1Aly1Ga1−x1−y1N/Inx2Aly2Ga1−x2−y2N multiple-quantum wells (MQWs) fabricated on SiC by metalorganic vapor phase epitaxy. We found that the UV emission is considerably enhanced upon introducing approximately 5% of In into AlGaN. Maximally efficient emission was obtained at 318 nm from the fabricated In0.05Al0.34Ga0.61N/In0.02Al0.60Ga0.38N three-layer MQW when the QW thickness was approximately 1.4 nm. The intensity of 320 nm band emission from the InAlGaN-based MQWs was as strong as that of 410 nm band emission from InGaN-based QWs at RT. We observed emission fluctuations of submicron size in cathode luminescence images of Inx1Aly1Ga1−x1−y1N/Inx2Aly2Ga1−x2−y2N single QW which might be due to In segregation effect. The temperature dependence of photoluminescence emission for InAlGaN-based QWs was greatly improved in comparison with that of GaN- or AlGaN-based QWs.

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We demonstrate a chemical route to depositing nickel granular layer patterns using ion-doped precursor templates, which can be used as adhesive interlayers for fabrication of copper circuit patterns on glass substrates. The poly(amic acid) templates were first dispensed from solution onto the glass surface using a fine-precision dispenser, followed by Ni 2+ ion doping through selective ion exchange reaction. The reduction treatment using aqueous NaBH 4 solution allowed the formation of a nickel granular layer on the poly(amic acid) surface, which could catalyze subsequent electrodeposition of copper. The resulting copper/nickel/polyimide-layered structure showed good adhesion with the glass substrate. This work can benefit the understanding of the growth process of metallic thin films via the direct metallization process and provide important experimental data for developing novel fabrication processes for copper circuit patterns on glass substrates.

The development of a sensitive and rapid diagnostic test for early detection of infectious viruses is urgently required to defend against pandemic and infectious diseases including seasonal influenza. In this study, we developed noble metal (Au, Pt) nanoparticle-latex nanocomposite particles for use as probes for immunochromatographic test (ICT) strips. The nanocomposite particles were conjugated with monoclonal antibody (mAb) to detect an influenza A (H1N1) antigen. For comparison, Au nanoparticles conjugated with mAb were also prepared. The lowest detectable concentrations of the influenza A antigen were found to be 6.25 × 10 and 2.5 × 10 HAU/mL for Au nanoparticle-latex and Pt nanoparticle-latex nanocomposite particles, respectively, whereas it was 4.0 × 10 HAU/mL for Au nanoparticles. These results clearly demonstrated that the nanocomposite probes were more sensitive than conventional nanoparticle-based probes for ICT. To expand the versatility of the nanocomposite probes, the surfaces of the probes were functionalized with biotinylated proteins to enable modification of their surfaces with desired biotinylated antibodies through biotin-avidin binding.