Abstract: A manufacturing method of a ring-shaped element for an etcher, comprises a granulation operation comprising i) a slurry manufacturing process of preparing a slurry by mixing a raw material including boron carbide, a sinterability enhancer with a solvent; and ii) a granulation process of drying the slurry to prepare granulated raw material; a molding operation of manufacturing a green body by molding the granulated raw material; a sintering operation of carbonizing and sintering the green body to manufacture a sintered body; a shape operation of shaping the sintered body to a ring-shaped element for an etcher. The sinterability enhancer comprises one selected from the group consisting of carbon, boron oxide and combinations thereof.

Abstract: A boron carbide sintered body includes necked boron carbide-containing particles. The thermal conductivity of the boron carbide sintered body at 400° C. is 27 W/m·K or less and the ratio of the thermal conductivity of the boron carbide sintered body at 25° C. to that of the boron carbide sintered body at 800° C. is 1:0.2 to 1:3.

Abstract: A ring-shaped element for an etcher includes a body portion having an outer diameter surface connecting an outer contour of an upper surface and an outer contour of a bottom surface, and an inner diameter surface connected to an inner contour of the upper surface, and a mounting portion having an upper surface connected to the inner diameter surface of the body portion at a position lower than the upper surface of the body portion, and an inner diameter surface connecting an inner contour of the upper surface and an inner contour of a bottom surface. The upper surface of the mounting portion is stepped from the upper surface of the body portion to constitute a substrate mounting portion. The surface or entire body of the ring-shaped element includes necked boron carbide-containing particles, and the thermal conductivity of the ring-shaped element at 400° C. is 27 W/m·K or less.

Abstract: The invention relates to a binder for binding RBSC (reaction-bonded silicon carbide), which is used to prepare RBSC assembly, wherein it includes a sintered body obtained by sintering a mixed powder of at least one substance selected from the group having Al, Ti, Fe, Mg, Cu and Ge, and silicon, or a powder obtained by milling the sintered body; and with regard to the mixing ratio of the mixed powder, the maximum amount of silicon is an amount rendering the complete melting temperature of phase in phase diagram of the mixed powder to be at most 1400° C., and the minimum amount of silicon is a larger value of either 50 at % or the minimum amount of silicon in silicon+liquid phase zone of the phase diagram, and a method of binding RBSC using the same.