Attenuating phase shift mask blank and photomask
AssigneesSchott AG, IBM Corporation
InventorsHans Becker, Ute Buttgereit, Gunter Hess, Oliver Goetzberger, Frank Schmidt, Frank Sobel, Markus Renno, S. Jay Chey
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Abstract
The present invention relates to attenuating phase shift mask blanks for use in lithography, a method of fabricating such a mask blank.
Claims50
An attenuating phase shift mask for use in lithography, comprising a substrate and a thin film system on one surface of said substrate;
- said thin film system comprising:
- a phase shift layer comprising a phase shift control sublayer and a transmission control sublayer;
- said phase shift mask being suitable for use in producing a photomask with substantially 180° phase shift and an optical transmission of at least 0.001% at an exposure light having a wavelength of 200 nm or less;
- wherein said thin film system is essentially free of defects having a particle size of 0.5 μm or more, and said transmission control sublayer comprises a material selected from the group consisting of Mg, Y, La, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Zn, Ge, Sn, Pb, nitrides thereof and mixtures of two or more of these metals or nitrides.
An attenuating phase shift mask for use in lithography, comprising a substrate and a thin film system on one surface of said substrate;
- said thin film system comprising:
- a phase shift layer comprising a phase shift control sublayer and a transmission control sublayer;
- said phase shift mask being suitable for use in producing a photomask with substantially 180° phase shift and an optical transmission of at least 0.001% at an exposure light having a wavelength of 200 nm or less;
- wherein the phase shift of said phase shift mask has a deviation from the mean value of at most about ±520 and the transmission of said phase shift mask has a deviation from the mean transmission value of at most about ±5%.
An attenuating phase shift mask for use in lithography, comprising a substrate and a thin film system on one surface of said substrate;
- said thin film system comprising:
- a phase shift layer comprising a phase shift control sublayer and a transmission control sub layer;
- said phase shift mask being suitable for use producing a photomask with substantially 180° phase shift and an optical transmission of at least 0.001% at an exposure light having a wavelength of 200 nm or less;
- wherein said thin film system is essentially free of defects having a particle size of 0.5 μm or more, and wherein said thin film system has at most 50 defects having a particle size of from 0.3 to 0.5 μm.
An attenuating phase shift mask for use in lithography, comprising a substrate and a thin film system on one surface of said substrate;
- said thin film system comprising:
- a phase shift layer consists of a phase shift control sublayer and a transmission control sublayer;
- said phase shift mask being suitable for use producing a photomask with substantially 180° phase shift and an optical transmission of at least 0.00 1% at an exposure light having a wavelength of 200 nm or less;
- wherein said thin film system is essentially free of defects having a particle size of 0.5 μm or more.
Dependencies are inferred from the claim text.