This study was carried out in an effect to deposit a transparent, preferentially c-axis oriented AlN film by a reactive ion plating method, in which aluminum metal and nitrogen gas were used as the evaporative source and reactive gas. Experiments were carried to investigate the influence on the c-axis orientation of the thin film of such deposition conditions as distance between hearth and substrate, substrate temperature, applied voltage and ionization current. The hardness of the AlN thin film was measured to examine the effect of these conditions on the quality of the structure of the thin films. The most highly c-axis oriented and transparent AlN films were deposited by reducing the distance between the hearth and the substrate from 500mm to 270mm. Substrate temperatures between 400°C and 450°C were adequate for the deposition of highly c-axis oriented films and they reached a maximum hardness of KK 3000 at these temperatures. The influence of applied voltage on the c-axis orientation was noticeable, but the degree of orientation did not change regularly with the change in applied voltage. The hardness of the films reached HK 3200 at an applied voltage of 0.2kV, and then decreased with further increases in voltage. The c-axis orientation was noticeable with the increase in ionization currents of 2∼8A, and hardness of films reached from HK 3400 to 3600, increasing abruptly under ionization currents of 8∼10A.
A study was conducted on polyester adhesives that can be activated at lower temperatures for the production of polyvinyl chloride (PVC) coated steel sheet by film lamination. Functional groups -OH, COOH, tertiary-amine, epoxy, etc. -were introduced in modified polyester resins as branches, and the effect on PVC film adhesion of the resultant variations in equivalent and molecular weights were examined. The addition of curing agents and catalysts to the modified polyester resins was also investigated. It was found that modified polyester resins containing these functional groups as branches gave insufficient PVC film adhesion at lower lamination temperatures, and that the addition to the modified polyester of MDI-type blocked isocyanate and the phenolic amide of DBU brought about good PVC film adhesion at a lower temperature (1800°C).
Microcrystalization of Au-Cu or Au-As alloy plated films was investigated, and it was found that at low current densities the grain size of Au-Cu plated films tends to decrease with an increase in Cu concentration. The above fact may be understood by considering the formation of an Au-Cu solid solution. The presence of As species in the Au plating baths raised the limiting current density and accelerated the rate of nucleation, so that the grain size of the Au-As film decreased. Pulse plating of Au, Au-Cu and Au-As alloys from sulfite baths was investigated with respect to the effect of pulse electrolysis on the grain size and morphology of the plated films. The results showed no difference between DC-plated and pulse-plated films.
The relationship between solderability and the structure of Ni-metallic Sn composites electroplated from Watts Ni baths, with and without brightener, were studied by scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. Solderability was evaluated by measurement of the spread of Sn-Pb alloy particles placed on composites kept at 240C for 5 seconds. The Sn content of composites plated with brightener was increased to 18wt% with only 1g/L of Sn particles in the bath, but the Sn content of composites plated without brightener was increased to 22wt% with 2g/L of Sn in the bath. Composites plated with brightener showed poor solderability irrespective of the Sn content, but the solderability of composites plated without brightener was excellent and increased linearly with increases in their Sn content. The differences in solderability were found to be the result of differences in the coverage of Ni on composite surfaces. Irrespective of the presence or absence of brightener, the surfaces of the codeposited Sn particles were covered with a thin film of Sn oxide. In the presence of brightener, a large part of the surface of the Sn particles was covered with deposited Ni, while in the absence of brightener, coverage of the Sn with Ni was negligible, leading to good solderability.
Ni-S amorphous alloy film was deposited by a method using an electroplating bath containing Na2S2O3, and the deposition conditions were considered in detail. The structure of the Ni-S alloy film changed with changes in plating current density, Na2S2O3 concentration and bath pH, but the structual changes were determined by changes in the S content in the deposited film. X-ray diffraction patterns showed that films containing about 40 at %S consisted of amorphous alloy. The process of Ni-S alloy film deposition was studied by means of electrochemical polarization and controlled potential plating methods.
TiN films were deposited under different bias voltages onto SUS304 stainless steel substrates by a hollow cathode discharge (HCD) type ion plating process. The corrosion resistance of the TiN-coated specimens in the active region was estimated in aqueous solutions of sulfuric acid, mainly by an electrochemical method. The adherence between the TiN film and stainless steel substrate was improved by applying a bias voltage, and the films deposited using a bias voltage exhibited a dense and distinct columnar structure. Measurements of the anodic polarization curves showed that the critical current density for passivation of the TiN-coated specimens was smaller than that for specimens without a TiN coating, that is, that active dissolution was retarded by TiN coating. The corrosion resistance of the TiN-coated specimens was further improved by applying a bias voltage, and this is attributed to the fact that the bias voltage decreased the amount of defects in the TiN films, that is, increased the intercepting effect of the film from it's surroundings. A compressive stress existed in the TiN films, the magnitude of which depended on the bias voltage. Moreover, there appeared to be good a correlation between the residual stress in the film and the corrosion resistance of the coated specimens.