Superior electrical contact characteristics of Ag/CNT composite films formed in a cyanide-free plating bath and tested against corrosion by H2S gas

Materials Letters. 303, 130504 (2021)journal articl

Electrodeposition of Ag/CNT Composite Films from Iodide Plating Baths

Ag/carbon nanotube (CNT) composite films were prepared by electrodeposition from non-cyanide baths. An iodide bath and multiwalled CNTs were used. The stability of the iodide bath under ambient conditions at various pH levels was examined, along with the changes in visual appearance, pH, and triiodide ion (I-3(-)) concentration. The electrodeposition was conducted under galvanostatic conditions using iodide baths with and without CNTs. The microstructure of the Ag and Ag/CNT composite films was characterized, and the hardness, electrical conductivity, and coefficient of friction of the films were measured. The iodide bath was stable at higher pH levels under ambient conditions. The obtained Ag/CNT composite films exhibited a compact structure, and CNTs were homogeneously distributed in the interior of the deposited Ag matrix. The CNT content in the deposits increased with increasing CNT concentration in the plating bath. The hardness of the Ag/1.2 mass%-CNT composite film was 63.2 HV, which was slightly greater than that of the Ag film (60.4 HV). The resistivity of the composite film was 1.9 mu omega cm, which was slightly higher than that of the pure Ag film (1.8 mu omega cm). The coefficient of friction of the composite film was lower than that of the Ag film.ArticleJOURNAL OF THE ELECTROCHEMICAL SOCIETY. 167(12):122515 (2020)journal articl

シリコン基板上への不整合界面を制御した誘電体のヘテロエピタキシャル成長

北陸先端科学技術大学院大学 / 金沢大学工学部研究課題/領域番号:04750246, 研究期間(年度):1992出典：研究課題「シリコン基板上への不整合界面を制御した誘電体のヘテロエピタキシャル成長」課題番号04750246（KAKEN：科学研究費助成事業データベース（国立情報学研究所）） （https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-04750246/）を加工して作

Fabrication of Roughened Electrodeposited Copper Coating on Steel for Dissimilar Joining of Steel and Thermoplastic Resin

Metals. 11(4), 591 (2021)journal articl

Superior Durability of Dissimilar Material Joint between Steel and Thermoplastic Resin with Roughened Electrodeposited Nickel Interlayer

The durability of the dissimilar material joint between a steel coated with a roughened nickel plating-film and a thermoplastic resin is assessed. The roughened nickel film is fabricated by electrodeposition using carbon nanotubes (CNTs) as the roughening agent and a polyphenylenesulfide (PPS) resin as the thermoplastic resin. The plated steel and PPS resin are joined by injection molding without adhesive. The bonding strength is determined by a tensile lap shear strength test during the durability tests that includes a high-temperature and high-humidity test (85 +/- 2 degrees C, 85 +/- 2% relative humidity; 0-2000 h) and a thermal shock test (-50 degrees C-150 degrees C; 0-1000 cycles). During the high-temperature and high-humidity test, the bonding samples maintain their initial bonding strength (>40 MPa) even after 2000 h. By contrast, during the thermal shock test, although the bonding strength gradually decreases with increasing number of cycles, it remains above 20 MPa even after 1000 cycles. The mechanism of the deterioration of the bonding strength during the thermal shock test is analyzed in detail. The present joining method, which uses a roughened plating film as an interlayer, offers a way to achieve not only high initial bonding strength but also bonding durability for dissimilar material joining between steels and resins.ArticleADVANCED ENGINEERING MATERIALS. 22(12):2000739 (2020)journal articl

Liver transplantation for patients with human immunodeficiency virus and hepatitis C virus coinfection with special reference to hemophiliac recipients in Japan.

Liver transplantation for patients with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) remains challenging. The advent of highly active antiretroviral therapy (HAART) for HIV has reduced mortality from opportunistic infection related to acquired immunodeficiency syndrome dramatically, while about 50% of patients die of end-stage liver cirrhosis resulting from HCV. In Japan, liver cirrhosis frequently develops after HCV-HIV coinfection resulting from previously transfused infected blood products for hemophilia. The problems of liver transplantation for those patients arise from the need to control calcineurin inhibitor with HAART drugs, the difficulty of using interferon after liver transplantation with HAART, and the need to control intraoperative coagulopathy associated with hemophilia. We review published reports of liver transplantation for these patients in the updated world literature

Low-Temperature Crystallization of Silicon Films Directly Deposited on Glass Substrates Covered with Yttria-Stabilized Zirconia Layers

Si films were deposited at low temperatures on glass substrates covered with poly-yttria-stabilized zirconia (YSZ) layers. We investigated the dependences of crystallization on the Y content and cleaning solution for the YSZ layers. Transmission electron microscopy showed that some regions of the Si film deposited at 430 °C were directly crystallized on a YSZ layer without an amorphous region, where Si lattice fringes were tightly connected to YSZ lattice fringes. The crystallization of Si films on YSZ layers occurred at deposition temperatures lower than that on glass substrates by more than 100 °C. Zr, Y, and F concentrations in the Si film were negligible, except the Zr concentration near the interface. The discussion on the crystallization mechanism gave the following suggestions on the method of obtaining a high crystalline fraction. The YSZ layer should be chemically cleaned using a solution containing HF before Si film deposition, and the content ratio Y/(Zr+Y) of YSZ should be ≳ 0.2

Dependences of deposition rate and OH content on concentration of added trichloroethylene in low-temperature silicon oxide films deposited using silicone oil and ozone gas

We investigated the dependences of the deposition rate and residual OH content of SiO_2 films on the concentration of trichloroethylene (TCE), which was added during deposition at low temperatures of 160-260 °C with the reactant gases of silicone oil (SO) and O_3. The deposition rate depends on the TCE concentration and is minimum at a concentration of ~0.4 mol/m^3 at 200 °C. The result can be explained by surface and gas-phase reactions. Experimentally, we also revealed that the thickness profile is strongly affected by gas-phase reaction, in which the TCE vapor was blown directly onto the substrate surface, where it mixed with SO and O_3. Furthermore, it was found that adding TCE vapor reduces residual OH content in the SiO_2 film deposited at 200 °C because TCE enhances the dehydration reaction

Effect of trichloroethylene enhancement on deposition rate of low-temperature silicon oxide films by silicone oil and ozone

A low-temperature silcon oxide film was deposited at 160 to 220 °C using an atmospheric pressure CVD system with silicone oil vapor and ozone gases. It was found that the deposition rate is markedly increased by adding trichloroethylene (TCE) vapor, which is generated by bubbling TCE solution with N_2 gas flow. The increase is more than 3 times that observed without TCE, and any contamination due to TCE is hardly observed in the deposited Si oxide films from Fourier transform infrared spectra