Photomask blank, photomask, and methods of manufacturing the same
AssigneeHoya Corporation
InventorOsamu Nozawa
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Abstract
A photomask blank has a light-shielding film composed of at least two layers on a transparent substrate. The light-shielding film includes a light-shielding layer made of a material mainly containing tantalum nitride and further containing xenon and a front-surface antireflection layer formed on the light-shielding layer and made of a material mainly containing tantalum oxide and further containing argon.
Claims24
A reflective mask blank having, on a substrate, a multilayer reflective film and an absorber film comprising at least two layers,
- wherein the absorber film comprises:
- an absorber layer made of a material mainly containing tantalum nitride and further containing xenon, the absorber layer is formed by sputtering using a sputtering target made of tantalum or a material mainly containing tantalum and using a mixed gas of a xenon gas and a nitrogen-based gas as a sputtering gas;
- and
- a surface antireflection layer formed on the absorber layer, the surface antireflection layer being made of a material mainly containing tantalum oxide and further containing argon, the surface antireflection layer is formed by sputtering using a sputtering target made of tantalum or a material mainly containing tantalum and using a mixed gas of an argon gas and an oxygen-based gas as a sputtering gas,
- wherein the absorber layer has a compressive stress while the surface antireflection layer has a tensile stress, and
- the compressive stress and the tensile stress are cancelled by each other to reduce an internal stress of the absorber film as a whole.
A method of manufacturing a reflective mask blank having a multilayer reflective film on a substrate, the method comprising:
- forming, on the multilayer reflective film, an absorber layer made of a material mainly containing tantalum nitride, by sputtering using a sputtering target made of tantalum or a material mainly containing tantalum and using a mixed gas of a xenon gas and a nitrogen-based gas as a sputtering gas;
- and
- forming, on the absorber layer, a surface antireflection layer made of a material mainly containing tantalum oxide, by sputtering using the sputtering target made of tantalum or the material mainly containing tantalum and using a mixed gas of an argon gas and an oxygen-based gas as a sputtering gas,
- wherein the absorber layer has a compressive stress while the surface antireflection layer has a tensile stress, and
- the compressive stress and the tensile stress are cancelled by each other to reduce an internal stress of an absorber film as a whole, the absorber film comprising the absorber layer and the surface antireflection layer.
A method of manufacturing a reflective mask blank having a multilayer reflective film on a substrate, the method comprising:
- forming, on the multilayer reflective film, an absorber layer made of a material mainly containing tantalum nitride, by sputtering using a sputtering target made of a sintered body of tantalum and boron, and using a mixed gas of a xenon gas and a nitrogen-based gas as a sputtering gas;
- and
- forming, on the absorber layer, a surface antireflection layer made of a material mainly containing tantalum oxide, by sputtering using the sputtering target made of the sintered body of tantalum and boron, and using a mixed gas of an argon gas and an oxygen-based gas as a sputtering gas,
- wherein the absorber layer has a compressive stress while the surface antireflection layer has a tensile stress, and
- the compressive stress and the tensile stress are cancelled by each other to reduce an internal stress of an absorber film as a whole, the absorber film comprising the absorber layer and the surface antireflection layer.
A reflective mask blank having, on a substrate, a multilayer reflective film and a layered film comprising at least two layers,
- wherein the layered film comprises:
- a first layer made of a material mainly containing tantalum nitride and further containing xenon, the first layer is formed by sputtering using a sputtering target made of tantalum or a material mainly containing tantalum and using a mixed gas of a xenon gas and a nitrogen-based gas as a sputtering gas;
- and
- a second layer formed on the first layer, the second layer being made of a material mainly containing tantalum oxide and further containing argon, the second layer is formed by sputtering using a sputtering target made of tantalum or a material mainly containing tantalum and using a mixed gas of an argon gas and an oxygen-based gas as a sputtering gas,
- wherein the first layer has a compressive stress while the second layer has a tensile stress, and
- the compressive stress and the tensile stress are cancelled by each other to reduce an internal stress of the layered film as a whole.
A method of manufacturing a reflective mask blank having a multilayer reflective film on a substrate, the method comprising:
- forming, on the multilayer reflective film, a first layer made of a material mainly containing tantalum nitride, by sputtering using a sputtering target made of tantalum or a material mainly containing tantalum and using a mixed gas of a xenon gas and a nitrogen-based gas as a sputtering gas;
- and
- forming, on the first layer, a second layer made of a material mainly containing tantalum oxide, by sputtering using the sputtering target made of tantalum or the material mainly containing tantalum and using a mixed gas of an argon gas and an oxygen-based gas as a sputtering gas,
- wherein the first layer has a compressive stress while the second layer has a tensile stress, and
- the compressive stress and the tensile stress are cancelled by each other to reduce an internal stress of a layered film as a whole, the layered film comprising the first layer and the second layer.
A method of manufacturing a reflective mask blank having a multilayer reflective film on a substrate, the method comprising:
- forming, on the multilayer reflective film, a first layer made of a material mainly containing tantalum nitride, by sputtering using a sputtering target made of a sintered body of tantalum and boron, and using a mixed gas of a xenon gas and a nitrogen-based gas as a sputtering gas;
- and
- forming, on the first layer, a second layer made of a material mainly containing tantalum oxide, by sputtering using the sputtering target made of the sintered body of tantalum and boron, and using a mixed gas of an argon gas and an oxygen-based gas as a sputtering gas,
- wherein the first layer has a compressive stress while the second layer has a tensile stress, and
- the compressive stress and the tensile stress are cancelled by each other to reduce an internal stress of a layered film as a whole, the layered film comprising the first layer and the second layer.
Dependencies are inferred from the claim text.