Abstract: In one aspect of the present disclosure, there is provided an optical wavelength conversion member including a polycrystalline ceramic sintered body containing, as main components, Al2O3 crystal grains and crystal grains represented by formula X3Al5O12:Ce. In the optical wavelength conversion member 9, atoms of element X are present also in an Al2O3 crystal grain adjacent to the interface between the Al2O3 crystal grain and an X3Al5O12:Ce crystal grain.

Abstract: There is provided a method for processing a semiconductor wafer subjected to a chamfering process, a lapping process, an etching process, and a mirror-polishing process, wherein acid etching is performed after alkaline etching as the etching process, and the acid etching is performed with an acid etchant composed of hydrofluoric acid, nitric acid, phosphoric acid, and water, a method for processing a semiconductor wafer subjected to a chamfering process, a surface grinding process, an etching process, and a mirror-polishing process, wherein the etching process is performed as described above, and a method for processing a semiconductor wafer subjected to a flattening process, an etching process, and a mirror-polishing process, wherein the etching process is performed as described above, a back surface polishing process is performed after the acid etching as the mirror-polishing process, and then a front surface polishing process is performed.

Abstract: There is provided a method for processing a semiconductor wafer subjected to a chamfering process, a lapping process, an etching process, and a mirror-polishing process, wherein acid etching is performed after alkaline etching as the etching process, and the acid etching is performed with an acid etchant composed of hydrofluoric acid, nitric acid, phosphoric acid, and water, a method for processing a semiconductor wafer subjected to a chamfering process, a surface grinding process, an etching process, and a mirror-polishing process, wherein the etching process is performed as described above, and a method for processing a semiconductor wafer subjected to a flattening process, an etching process, and a mirror-polishing process, wherein the etching process is performed as described above, a back surface polishing process is performed after the acid etching as the mirror-polishing process, and then a front surface polishing process is performed.

Abstract: A reaction tube without occurrence of crack or breakdown or a wafer boat without generation of particles is provided, such various faults being caused by the difference between the thermal expansion coefficients of a thin film and one of those quartz glass jigs. The present invention is applied to a quartz glass jig used in a thermal CVD apparatus, and is characterized in that the jig is made of transparent quartz glass material, and that the portion or portions exposed to the heat treatment space or the portions contacting with wafers are sand-blasted. The reason why transparent quartz glass is limited as the material is that, in case of transparent quartz glass, the surface hardness is more uniform in comparison to bubble-mixed or opaque quartz glass and thus a predetermined surface roughness is more effectively achieved by sand-blasting so that the faults as mentioned above due to the stress occurring in the treatment between a CVD film and one of the quartz glass jigs are effectively prevented.

Abstract: The single crystal silicon wafers which have undergone a treatment with a chemical liquid such as an acid or an alkali are stored without entailing contamination of their surfaces by causing the wafers to be immediately immersed, either directly or after being washed with water, in an aqueous hydrogen peroxide solution. The prevention of the contamination of surfaces of the wafers is attained effectively by setting the concentration of hydrogen peroxide in the aqueous hydrogen peroxide solution in the range of from 0.01 to 30% by weight and the temperature of the aqueous hydrogen peroxide solution at the time that the wafers are immersed in the solution in the range of from 10.degree. to 30.degree. C.