Abstract: An ion implantation results in defects generated in a nitride semiconductor layer. If the nitride semiconductor layer is set at a particular temperature for a predetermined time period after the ion implantation, the defects may probably be clustering. Provided is a manufacturing method of a semiconductor device including a nitride semiconductor layer comprising: implanting impurities in the nitride semiconductor layer; and increasing a temperature of the nitride semiconductor layer from an initial temperature to a target temperature and annealing the nitride semiconductor layer at the target temperature for a predetermined time period; wherein in the annealing, in at least part of temperature regions below a first temperature between the initial temperature and the target temperature, the nitride semiconductor layer is annealed at a temperature increase speed lower than in a temperature region not lower than the first temperature.

Abstract: An ion implantation results in defects generated in a nitride semiconductor layer. If the nitride semiconductor layer is set at a particular temperature for a predetermined time period after the ion implantation, the defects may probably be clustering. Provided is a manufacturing method of a semiconductor device including a nitride semiconductor layer comprising: implanting impurities in the nitride semiconductor layer; and increasing a temperature of the nitride semiconductor layer from an initial temperature to a target temperature and annealing the nitride semiconductor layer at the target temperature for a predetermined time period; wherein in the annealing, in at least part of temperature regions below a first temperature between the initial temperature and the target temperature, the nitride semiconductor layer is annealed at a temperature increase speed lower than in a temperature region not lower than the first temperature.

Abstract: A focus ring is shaped by cutting off a silicon carbide body formed by a sintering method or a CVD method. The shaped focus ring is exposed to a plasma generated from at least one of a carbon tetra fluoride gas and an oxygen gas for producing impurities, and the impurities are introduced to void-like defects existing in the vicinity of a surface of the focus ring. Subsequently, positrons are injected in the vicinity of the surface of the focus ring into which the impurities are introduced, and the defect density in the vicinity of the surface of the focus ring is detected by the positron annihilation method.

Abstract: A focus ring is shaped by cutting off a silicon carbide body formed by a sintering method or a CVD method. The shaped focus ring is exposed to a plasma generated from at least one of a carbon tetra fluoride gas and an oxygen gas for producing impurities, and the impurities are introduced to void-like defects existing in the vicinity of a surface of the focus ring. Subsequently, positrons are injected in the vicinity of the surface of the focus ring into which the impurities are introduced, and the defect density in the vicinity of the surface of the focus ring is detected by the positron annihilation method.

Abstract: Disclosed is a defect evaluation apparatus comprising a source section having a source for generating positrons and a moderator for decelerating the positrons, a sample holding section for holding a sample to be measured, a transfer section for transferring the positrons from the source section to the sample holding section, and detection means for detecting ? rays emitted from the sample being measured, characterized in that the apparatus further comprises heating means for heating the moderator in a position where there is a possibility of the source being thermally damaged if there is no protection means mentioned below in the source section, and protection means for protecting the source from the heating means and heated moderator when the moderator is being heated using the heating means.

Abstract: Disclosed is a defect evaluation apparatus comprising a source section having a source for generating positrons and a moderator for decelerating the positrons, a sample holding section for holding a sample to be measured, a transfer section for transferring the positrons from the source section to the sample holding section, and detection means for detecting &ggr; rays emitted from the sample being measured, characterized in that the apparatus further comprises heating means for heating the moderator in a position where there is a possibility of the source being thermally damaged if there is no protection means mentioned below in the source section, and protection means for protecting the source from the heating means and heated moderator when the moderator is being heated using the heating means.