Fe2O3-Nb2O5 coating films of various Nb/(Fe + Nb) mole ratios were prepared on nesa silica glass substrates from Fe(NO3)3.9H2O - NbCl5 - CH3(CH2)2CH2OH - CH3COOH solutions by the sol-gel method. The photoanodic properties were studied in a three-electrode cell with an aqueous buffer solution of pH = 7 as the supporting electrolyte. The crystalline phases identified were alpha-Fe2O3 (Nb/(Fe + Nb) = 0), alpha-Fe2O3 + FeNbO4 (Nb/(Fe + Nb) = 0.25), FeNbO4 (Nb/(Fe + Nb) = 0.5), FeNbO4 + Nb2O5 (Nb/(Fe + Nb) = 0.75), and Nb2O5 (Nb/(Fe + Nb) = 1). When the Nb/(Fe + Nb) mole ratio increased from 0 to 0.25, the crystalline phases changed from alpha-Fe2O3 to alpha-Fe2O3 + FeNbO4, the photoanodic current under white light illumination increased, and the photoanodic current under monochromatized light illumination increased in both visible and ultraviolet regions. When the Nb/(Fe + Nb) ratio increased over 0.25, the crystalline phases changed to FeNbO4, FeNbO4 + Nb2O5, or Nb2O5, and the photoanodic current decreased. The sample consisting of alpha-Fe2O3 and FeNbO4 (Nb/(Fe + Nb) = 0.25) exhibited photoresponse extending to 600 nm and an IPCE of 18% at a wavelength of 325 nm.

We investigated the influence of ZrN/Zr bilayered film thickness on the (111) Cu orientation and the thermal stability of the Cu/ZrN/Zr/Si contact system by X-ray diffraction and Auger electron spectroscopy analyses. We confirmed that the single-oriented growth of (111) Cu can be realized by interposing the ZrN (400 Å)/Zr (200 Å) bilayered film between Cu and Si. It was revealed that the (111) Cu/(111) ZrN/(002) Zr/(001) Si contact system is satisfactorily stable up to 600°C without undesirable interfacial reaction and interdiffusion, maintaining the low contact resistivity of the ZrSi2 adhesion layer at the Si interface and the single-oriented state of the (111) Cu overlayer.

Ag nanoparticles were adsorbed onto epoxy and fluorine-doped tin oxide ͑FTO͒ glass substrates by dipping them into a Ag nanoparticle colloidal solution to catalyze the substrate for electroless Cu plating. Before the Ag nanoparticle adsorption, the substrates were conditioned with either a cationic surfactant, stearyltrimethylammonium chloride ͑STAC͒, or a cationic polyelectrolyte, poly͑diallyldimethylammonium chloride͒ ͑PDDA͒, both having quaternary amine headgroups. The adsorbed Ag nanoparticles catalyzed the HCHO oxidation reaction, thereby allowing the electroless Cu deposition reaction to start. For both the epoxy and the FTO glass substrates, conditioning with the concentrated PDDA solution having a 100 ϫ 10 −3 mol L −1 quaternary amine concentration was the most effective in producing the largest amounts of Ag nanoparticles to be adsorbed and in providing the fastest initial deposition rate of the electroless Cu plating. When the diluted conditioners were used, a comparison between the diluted STAC and PDDA showed that STAC was the more effective conditioner for the epoxy substrates, while PDDA was more effective for the FTO glass substrates. The effectiveness of STAC was attributed to the strong hydrophobic interaction with the epoxy substrate surface. However, the effectiveness of PDDA was attributed to the strong electrostatic interaction with the FTO glass surface.Electroless plating on polymer substrates is widely used in the automotive and electronics industries. 1 In particular, electroless Cu plating on epoxy or polyimide substrates is a crucial process during printed wiring board ͑PWB͒ manufacturing. 2 Many stages during the pretreatment for the electroless plating are required, such as surface roughening, substrate conditioning, catalyzing, and accelerating. The catalyzing process is essential to initiate the electroless plating.Polymer substrates are usually catalyzed by the adsorption of Pd/Sn mixed colloids from a solution. 3 The Pd/Sn mixed colloidal catalysts, however, do not appreciably adsorb on the epoxy surface; 4 therefore, a conditioning process for the substrates is needed. Luke 5 pointed out that cationic surfactants neutralize the negative charge of the epoxy surface and promote the adsorption of the negatively charged Pd/Sn mixed colloidal catalysts. It has also been reported that cationic polyelectrolytes are effective as substrate conditioners for introducing a positive surface charge. 4,6 Recent trends in the PWB design, which require electroless Cu plating to fabricate the narrower circuit lines at a lower cost, have revealed some disadvantages of the Pd/Sn mixed colloid catalysts. 7 For example, residual Pd beneath the photoresist permits the electroless Cu to be deposited between the circuit lines and causes an insulation decrease and short circuits. 4 In addition, the material cost of Pd has become increasingly expensive in recent years. Ag and Ag nanoparticles are effective as alternative catalysts to the Pd/Sn mixed colloids. [7][8][9] In a previous paper, 10 we have propo...

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