Thin Film Comprising Titanium Oxide as Main Component and Sintered Compact Sputternig Target Comprising Titanium Oxide as Main Component

An optical interference film or a protective film of an optical information recording medium which is formed by performing DC sputtering to a target comprising titanium oxide as its main component, wherein the film includes titanium, oxygen and platinum, content of Ti is 29.0% or higher and 34.0 at % or less and content of Pt is 0.003 at % or higher and 5.7 at % or less with the remainder being oxygen and unavoidable impurities, and ratio of oxygen component to metal components, O/(2Ti+Pt), is 0.95 or higher.

An optical interference film or a protective film of an optical information recording medium which is formed by performing DC sputtering to a target comprising titanium oxide as its main component, wherein the film includes titanium, oxygen and one or more types of metal M selected from cobalt, nickel, palladium and gold, content of Ti is 29.0% or higher and 34.0 at % or less and content of M is 0.003 at % or higher and 7.7 at % or less with the remainder being oxygen and unavoidable impurities, and ratio of oxygen component to metal components, O/(2Ti+M), is 0.95 or higher.

7-8. (canceled)

A sintered compact target for DC sputtering for forming an optical interference film or a protective film of an optical information recording medium comprising titanium oxide as its main component, wherein the target includes copper and comprises, as its main component, titanium oxide made of titanium, oxygen and unavoidable impurities as a remainder thereof, the respective components have a composition ratio of (TiO2-m)1-nCun(provided that 0≦m≦0.5 and 0.0001≦n≦0.2), and the target has a specific resistance of 100 Ωcm or less.

A sintered compact target for DC sputtering for forming an optical interference film or a protective film of an optical information recording medium comprising titanium oxide as its main component, wherein the target includes platinum and comprises, as its main component, titanium oxide made of titanium, oxygen and unavoidable impurities as a remainder thereof, the respective components have a composition ratio of (TiO2-m)1-nPtn(provided that 0≦m≦0.5 and 0.0001≦n≦0.15), and the target has a specific resistance of 100 Ωcm or less.

A sintered compact target for DC sputtering for forming an optical interference film or a protective film of an optical information recording medium comprising titanium oxide as its main component, wherein the target includes one or more types of metal M selected from cobalt, nickel, palladium and gold and comprises, as its main component, titanium oxide made of titanium, oxygen and unavoidable impurities as a remainder thereof, the respective components have a composition ratio of (TiO2-m)1-nMn (provided that 0≦m≦0.5 and 0.0001≦n≦0.2), and the target has a specific resistance of 100 Ωcm or less.