Experiments were conducted on the formation of boron compounds on pure iron and stainless steel substrates using BCl3 and NH3 as the reaction gases and Ar as the diluent gas. Samples were prepared by machining pieces of various iron and steel materials to a diameter of 6mm and a thickness of 1mm, and polishing the surfaces with diamond paste. Samples were heated in an infrared ray furnace. The following results were obtained. 1. For pure iron, S45C, SK3 and SKH55, the thickness of the boron compounds formed by reaction with the substrate material increased linearly with the length of the treatment time and with the reaction temperature. In the case of SUS304, however, peeling of the surface layer occurred, while in the case of SCM415, peeling occurred during polishing of the cross-section, making it impossible to obtain an accurate measurement of the thickness of the layer formed. 2. Disuniformities and vapor holes were observed on the surface of the layer of compounds formed, as the result of the vaporization of salts of Fe and Cr in the reaction tube. As a result of this, the concentration of Ni and Cr in the surface layer in the case of SUS304 was found to have increased relative to that in the inside of the surface layer.
The autocatalytic chemical deposition of lead has been achieved using titanium trichloride as the reducing agent. Lead film was deposited onto the non-conductive substrate to the intended thickness at a rate of 520Å/min. The optimum bath composition was; lead chloride 0.04M, trisodium citrate 0.20∼0.40M, disodium EDTA 0.08∼0.16M, NTA 0.20M, and titanium trichloride 0.03∼0.05M. The pH was 9.0 (adjusted with ammonia) and the temperature 60°C. Measurements of UV and visible absorption spectra revealed that NTA, EDTA and citric acid mainly formed complex salts with Ti3+, Pb2+ and Ti4+ respectively. X-ray diffraction analysis showed that the crystal structure of the deposited film was not affected by bath composition and plating condition.
Pt-Mo alloy films were obtained by electrodeposition from a plating bath containing H2PtCl6 and Na2MoO4, using ammonia alkaline baths, and the effects of electrolysis parameters on Pt and Mo content, the total current efficiency and the structure and thermal stability of Pt-Mo alloy films were investigated under varying conditions of electrolysis. Electrodeposited Pt-Mo alloy films were then studied by X-ray diffraction, DSC analysis and ESCA, and information on the structure of the alloy films was obtained. X-ray diffraction patterns showed that films containing about 10∼15 wt% Mo consisted of a mixture of amorphous and crystalline alloys. ESCA spectra of Mo 3d levels for the alloy films showed that these elements existed in a metallic state.
The anodic oxidation process of a-Si: H is a basic feature of integrated circuit technology. In the thermal oxidation method, the hydrogen will separate from the a-Si-to-H bond at a high temperature, so that anodic oxidation is well suited to the growth of film on amorphous silicon by plasma-chemical vapor deposition. Nevertheless, the electrolytic anodization process of a-Si: H film has not yet been investigated. A current interrupter technique was used to measure the resistance polarization, the differential capacity of the electric double layer, and the activation energy in the anodic oxidation of a-Si: H, and it has also been applied to the analysis of anodic oxidation in a variety of metals. The apparatus used was built using a mercury-wetted electromagnetic relay combined with an integrated circuit. The circuit based on this design made contact with an anodic electrode of a-Si: H and a cathodic electrode of platinum in ethyleneglycol solution. The characteristics of anocic behavior in SiO2 on a-Si were checked through the use of this system. The output waveforms of the transient phenomena were traced on a digital memory scope, and the data was sent to a computer over a GP-IB interface. In general, the differential capacity increases as the temperature rises at 2.5∼10mA cm-2. The Arrenius plots fully satisfied the linear relationship, and the calculated value of activation energy was about 14.5kJ mol-1.
The YBCO superconductor prepared by the electrophoretic deposition method has been studied. It is known that the electrophoretic deposition must be performed at high voltages to obtain material having high Jc. Stainless steel substrates having various coefficients of expansion were investigated to eliminate the microcracks that can form at high deposition voltages. The deposited samples were sintered at 940°C for 1h and annealed at 500°C for 1h. The results obtained are summarized as follows: (1) Microcracks occurred on ferrite stainless steel substrates. (2) Superconductors with high density and no cracks were obtained on austenitic stainless steel substrates. The optimum value of Tczero was 78K.
When gold plate was deposited from an acid solution of Au (CN)2- onto a nickel base having residual internal stress, observation by microscope revealed large numbers of pinholes around the strain. Stress-relief heat treatment was found to decrease pinhole formation. Internal stress inhibited uniform deposition. It is concluded that pinhole formation is due to the establishment of an anodic region.