The electronic structures of three principal low index surfaces of diamond and zinc blende type semiconductors are described from the standpoint of chemical bond energy. General features of gas adsorption on these surfaces are described briefly. In addition the basic method of calculation of energy band structure is added as introductory part.

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Methods of measuring surface diffusion coefficients and related phenomena have been reviewed. These include grain boundary grooving, sinusoidal profile decay, isolated scratch decay, tracer, ¹⁸O-exchange reaction, sintering, spheroidization of cylindrical voids, work function, etc. Most of the surface diffusion coefficients of oxides measured by these methods involve Al₂O₃, MgO and NiO. The activation energies of surface diffusion measured at low temperature were generally smaller than those measured at high temperature. In MgO and NiO, the surface diffusion coefficient of oxygen is slower than that of cations.
Methods of measuring surface layer thickness at elevated temperature are also reviewed and the results for oxides are summarized. In general, the surface layer thicknesses measured by solid state reaction are larger than those measured by ¹⁸O-exchange reaction.

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The adsorption of model compounds of lubricating oil components on the cut steel surfaces was carried out under high vacuum. The estimated amount of adsorption was less than a monolayer level. The adsorption of nitrogen and n-hexane was not observed. The other adsorbates used were divided into two groups according to their adsorption activity on the cut surface. Benzene, cyclohexene and diethyl disulfide exhibited a high adsorption activity, while, propionic acid, propyl amine and trimethyl phosphate exhibited comparatively low activity. It is noteworthy that the functional group of the latter compounds was characterized by a lower polarizability than that of the former. The results were discussed on the basis of HSAB (Hard and Soft Acids and Bases) principle.

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The morphology and friction coefficient associated with water content and lipid on the skin of the inner part of the forearm, were investigated in 250 healthy subjects. It was found by electron microscopy that skin surface exhibited a pattern formed by two types of stripes, main stripes and fine stripes and these differ in length and depth from the superficial surface of the skin. Total length of the stripes on the skin surface per unit area decreases gradually with age of subject, and the pattern of the skin surface in advanced age is mainly formed by the main stripes. Friction coefficient of the surface depends largely on the total length of the stripes per unit area. It increases monotonically with the decrease of the total length.
The relationship was investigated between water content and friction coefficient on skin surface, and it was found that there was an optimum water content to minimize friction coefficient of the skin surface.

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A study has been made on properties of fumed silica prepared from silicon tetrachloride in hydrogen combustion flames ranging from 1000 to 2200°C, while flame temperature in this study is determined by adiabatic calculation based on equilibrium conditions.
A marked change in properties occurred at temperatures around 1500-1700°C as evidenced by surface area, apparent refractive index, number of hydroxyl groups, and size of the primary particles.
The particular temperature of 1500-1700°C is considered to correspond to the melting point of silicon dioxide materials. At flame temperatures lower than 1500-1700°C numerous various size pores existed in the silica produced, then these silica particles were assumed to have grown in a non-melted phase. On the other hand, at higher temperature few pores existed and silica particles were assumed to have been grown in a melted phase.

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Copper whiskers with thick halide sheaths on their surface grow by reduction of CuCl where acetylene black is added. Typical whiskers possess <111> growth directions, {100} lateral surfaces and round terminations. A variation of VLS growth where a halide melt covers the surfaces of growing whiskers takes place on the growth.

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A new technique developed by Binning, Rohrer, Gerber and Weibel on scanning tunneling micro scopy (STM) is presented. STM gives surface topographies in real space and work function profiles on an atomic scale. The spatial resolution of STM is sub-Å in depth and several Å in lateral direction. Examples of its applications to determine the reconstructed structures of Si (111) 7×7 and Au (110) 2×1 are shown. Step formation on Si surfaces by annealing and growth phenomena of islands by vapor evaporation are also shown.

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Surface-selectively enriched Mössbauer absorbers were prepared from pure ⁵⁷Fe and ⁵⁶Fe isotopes and utilized for the studies of very thin oxide layers on Fe metal surfaces and also of magnetic properties of Fe interfaces in contact with V metal.
Multilayered films with artificial superstructures are briefly described. These are of recent interest from the viewpoint of new material fabrication.

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Diamond synthesis under thermodynamic metastability has been shown to be feasible by vapor deposition using hydrocarbon-hydrogen mixed gases. Three different methods, i.e., modified CVD using a hot tungsten filament and plasma assisted vapor depositions using microwave (2, 450MHz) and rf (13.5MHz) power are employed. Typical growth conditions are : methane concentration, ca. 1%; total pressure, 10-60 Torr; temperature, 700-1000°C. Diamond can be grown on diamond as well as on non-diamond substrates including Si, Mo, W, Ta, SiO₂, Al₂O₃ and BN. Structural identification of the deposits was performed by electron diffraction and Raman spectroscopy. Lattice spacings determined by RHEED agreed with those reported for diamond. X-ray diffraction pattern characteristic of diamond was observed for deposited films. Vapor-deposited diamond particles show well-defined morphology characteristic of diamond. They grow at a rate of 0.5-1μm/hr. The paticles are hard and readily give visible scratches on the surface of SiO₂, Al₂O₃, B and B₄C.

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Selective protection of a tooth surface against dental caries is afforded by producing a gold film on the tooth surface. A sputtering apparatus capable of giving sufficient film thickness on a tooth and some results of gold coatings on extracted teeth are described.

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