The nitriding performance of low power electron beam excited plasma was investigated by characterizing the compound layer formed on the surface of nitrided low alloy Cr-Mo steel specimens. In an attempt to maximize the dissociation of N2, the acceleration voltages applied in our experiments were set within a range that corresponds to the maximum dissociation cross section of N2. In this experiment, particular attention was given to the effect of the treatment time on the surface morphology, composition, and Vickers hardness of the treated specimen. The results show that the peak intensity of the alpha Fe observed for the untreated specimen decreased as the treatment time increased. Moreover, the peak intensities depicting the formation of the nitride compound layers, Fe4N and Fe3N phases, increased with the treatment time. Consequently, the surface hardness of the treated low alloy steel specimen was increased to 1010HV and a nitrided depth of up to 120μm was attained in 4.5 hours of treatment time.
Polytetrafluoroethylene (PTFE) sheet was treated in an atmospheric pressure plasma using a series of feed gases (Water, Methanol, Ethanol, and Acetone) and the resulting surface modifications were evaluated by water contact angle measurements and x-ray photoelectron spectroscopy (XPS). We found that all plasma treatments gave rise to the breakage of some C-F bond, resulting in defluorination and the formation of oxygen containing functional groups onto the PTFE surface. Electroless plating of copper (Cu) could be carried out effectively on the modified PTFE surface. The use of ethanol plasma caused unexpected improvement in the T-peel adhesion strength of the electrically deposited Cu layer on the treated PTFE substrate with approximately three-fold improvement over that for conventionally adopted sodium treatments.
In the basic concept of conventional electroplating, the additives, which determine the properties of the deposited film, are included in the plating bath. In this report, ULSI copper minute wiring formation by a new process is described. The process relies on the pre-adsorption of the polyethylene glycol bis (1, 2, 3-benzotriazolylether) [PBTA] synthesized from polyethylene glycol and benzotriazole, and copper electrodeposition from an acid copper sulfate bath without additives. The copper electrodeposition was done using an insoluble anode in the basic bath without additives after PBTA was pre-adsorbed on the silicon wafer with copper seed. The adsorbed PBTA on the surface of the copper seed strongly inhibited copper electrodeposition. In this process, a minute hole can be filled with copper without causing voids and seams due to the effect of site-selective adsorption of PBTA.
Polytetrafluoroethylene or PTFE is known as an excellent lubricant. In this study we examined the possibility of electrophoretic coating in a PTFE emulsion bath with silane coupling, and ammonium oxalate as an electrolyte on an anodic oxide film of aluminum. As the result, the coating showed good uniformity, durability and lubricity. The coating weight is in the range of 1–2 mgdm–2 and the kinetic friction coefficient value is in the range of 0.08–0.20. The silane coupling contributes to elevate the water resistance, adhesive property and lubricity of the coating.