Abstract: A photomask blank has at least one layer of chromium base film on a transparent substrate. The chromium base film of chromium oxycarbide (CrCO) or chromium oxynitride carbide (CrCON) is formed by a reactive sputtering technique using chromium or chromium containing O, N or C as the target and a mixture of carbon dioxide gas and an inert gas as the sputtering gas. A photomask is manufactured by lithographically patterning the photomask blank. The photomask blank and photomask are of quality featuring high uniformity within the substrate plane and ease of control during manufacture.

Abstract: A phase shift mask blank has a phase shift film of MoSiOC or MoSiONC on a transparent substrate, and optionally a chromium-based light-shielding film, a chromium-based antireflection film or a multilayer combination of both on the phase shift film. A manufacture method involving depositing the MoSi base phase shift film by a reactive sputtering technique using a sputtering gas containing carbon dioxide produces a phase shift mask blank and phase shift mask of quality, with advantages of in-plane uniformity and easy control during manufacture.

Abstract: In a method of fabricating an SOI wafer, an oxide film is formed on the surface of at least one of two silicon wafers; hydrogen ions or rare gas ions are implanted into the upper surface of one of the two silicon wafers in order to form a fine bubble layer (enclosed layer) within the wafer; the ion-implanted silicon wafer is superposed on the other silicon wafer such that the ion-implanted surface comes into close contact with the surface of the other silicon wafer via the oxide film; heat treatment is performed in order to delaminate a portion of the ion-implanted wafer while the fine bubble layer is used as a delaminating plane, in order to form a thin film to thereby obtain an SOI wafer. In the method, a defect layer at the delaminated surface of the thus-obtained SOI wafer is removed to a depth of 200 nm or more through vapor-phase etching, and then mirror polishing is performed. Therefore, the obtained SOI wafer has an extremely low level of defects and a high thickness uniformity.

Abstract: A method of cleaning atmosphere gas used in manufacturing high-purity fine particles of reactive metals comprises the steps of: letting the moisture existing in the atmosphere gas condense into dew droplets using a cryogenic cooling medium; removing the moisture defined by the dew droplets through dissociation by letting it react with metallic Na that has been brought into contact with the dew droplets; generating a vapor of metallic Na in the atmosphere gas so as to remove the moisture still persisting in the atmosphere gas; further removing through dissociation the moisture still persisting in the atmosphere gas by letting it react with Na vapor that has been generated and dispersed into the atmosphere gas; letting the atmosphere gas cleaned of moisture come into contact with black barium powder; and detecting the presence of moisture in the atmosphere gas through a change in color of the black barium powder.

Abstract: A method of making high-purity fine particles of reactive metals, reactive especially in terms of their inclination to form hydroxides, comprises the steps of: preparing an inert gas atmosphere within which to manufacture the particles; reducing the moisture remaining in the inert gas atmosphere to an extremely low level; pulverizing the reactive metal within the moisture-free inert gas atmosphere; and collecting and sealing the product particles of reactive metal in a storage container in the same moisture-free inert gas atmosphere.

Abstract: A method of making high-purity fine particles of reactive metals, reactive especially in terms of their inclination to form hydroxides, comprises the steps of: preparing an inert gas atmosphere within which to manufacture the particles; reducing the moisture remaining in the inert gas atmosphere to an extremely low level; pulverizing the reactive metal within the moisture-free inert gas atmosphere; and collecting and sealing the product particles of reactive metal in a storage container in the same moisture-free inert gas atmosphere.