Abstract: An electron emission film having a pattern of diamond in X-ray diffraction and formed of a plurality of diamond fine grains having a grain diameter of 5 nm to 10 nm is formed on a substrate. The electron emission film can restrict the field intensity to a low level when it causes an emission current to flow, and has a uniform electron emission characteristic.

Abstract: A photoelectric conversion device comprising: a pin-type photoelectric conversion layer constituted of a p-type semiconductor layer, an i-type semiconductor layer and an n-type semiconductor layer, wherein the p-type semiconductor layer contains silicon atoms and nitrogen atoms, which is possible to improve photoelectric conversion efficiency.

Abstract: The principal objects of the invention is to provide diamond fine particles with a surface nature so improved as to form a stable, uniform suspension or dispersion in a common medium such as water and alcohol. Another object is to provide an effective technique for producing hydrophilic diamond fine particles by chemically modifying the particle surface nature, while removing at the same time contaminants and foreign materials which coexist with the diamond. In the invention, diamond particles are treated by boiling in the treatment fluid of sulfuric acid solution, which is in particular of concentrated or fuming nature, at a temperature more than 200° C., which is preferably 250° C. or more.

Abstract: The present invention provides a superhard film-coated member having a diamond or diamond-like carbon film strongly bonded to a cemented carbide substrate and a method of manufacturing such a member. The cemented carbide substrate is subjected to heat treatment to cause the bonding metal in a region of the substrate near to its surface to migrate to the surface so as to form hemispherical deposits thereon. The deposits are left undisturbed or a part or all thereof are removed, and subsequently diamond and/or diamond-like carbon is grown on the substrate surface by a chemical vapor deposition process. The deposits formed on the substrate surface have the effect of significantly improving the bonding strength between the superhard films and the cemented carbide substrate to allow formation of thicker film coatings.

Abstract: A method is provided for efficiently producing an entirely quality-controlled CVD diamond. A CVD process is interrupted at an early stage and the deposit is taken out of the reaction chamber, before a significant mass is accumulated, and is inspected by means of cathodoluminescence. The spectrum are compared with a given reference in terms of peak position, half width and 20%-value width in coordination. The observed deviation allows to determine whether to maintain or alter the settings.A diamond substance of acceptable quality which is properly specified in terms of the CL parameters is also provided.

Abstract: Making a diamond substance exhibiting a cathodoluminescence spectrum with the peak at a photon energy greater than 2.8 eV (electron volt), the half-value and 20%-value width not exceeding 0.5 eV and 0.8 eV, respectively, comprising: providing a substrate in a closed chamber, introducing a matrix gas comprising H.sub.2 and one selected from hydrocarbon and CO to said chamber, exciting the gas to create a plasma while heating said substrate to a temperature of at least 700.degree. C. and, thus, causing deposition and growth of diamond substance which is crystallographically diamond, controlling parameters of the deposition by means of the cathodoluminescence record and recovering the diamond substance from the chamber.