Abstract: The present invention provides a gallium nitride sintered body and a gallium nitride molded article which have high density and low oxygen content without using a special apparatus. According to the first embodiment, a gallium nitride sintered body, which is characterized by having density of 2.5 g/cm3 to less than 5.0 g/cm3 and an intensity ratio of the gallium oxide peak of the (002) plane to the gallium nitride peak of the (002) plane of less than 3%, which is determined by X-ray diffraction analysis, can be obtained. According to the second embodiment, a metal gallium-impregnated gallium nitride molded article, which is characterized by comprising a gallium nitride phase and a metal gallium phase that exist as separate phases and having a molar ratio, Ga/(Ga+N), of 55% to 80%, can be obtained.

Abstract: Provided is an apparatus that includes a molding die for producing a sintered body. The molding die is configured for cold isostatic pressing and includes a knockdown mold frame comprised of plural frame members and a bottom plate provided in contact with the knockdown mold frame. An upper punch is provided to be movable along the inner surface of the knockdown mold frame. The frame members configured to be movable relative to each other to accommodate an expansion of a green body which takes place at the time of reducing the pressure after the completion of pressing.

Abstract: There is provided a zinc oxide sintered compact with a zirconium content of 10 to 1000 ppm, and a sputtering target containing the zinc oxide sintered compact. There is also provided a zinc oxide thin-film having a zirconium content of 10 to 2000 ppm and a resistivity of 10 ?·cm or greater.

Abstract: Provided is an apparatus that includes a molding die for producing a sintered body. The molding die is configured for cold isostatic pressing and includes a knockdown mold frame comprised of plural frame members and a bottom plate provided in contact with the knockdown mold frame. An upper punch is provided to be movable along the inner surface of the knockdown mold frame. The frame members configured to be movable relative to each other to accommodate an expansion of a green body which takes place at the time of reducing the pressure after the completion of pressing.

Abstract: To provide a large sputtering target excellent in discharge characteristics during sputtering and in characteristics of a thin film thereby obtainable. Further, a process for producing a sintered body is provided, whereby a large green body excellent in shape accuracy can be obtained by means of cold isostatic pressing directly without preforming, and a sintered body capable of providing the above-mentioned excellent sputtering target, can be produced efficiently at a low cost. The sputtering target is produced by using a sintered body having the content of carbon contained as an impurity reduced to less than 0.005 wt %. Such a sintered body is obtainable by molding a raw material powder by cold isostatic pressing directly without adding a binder containing an organic substance or a molding aid, followed by firing.