Mask blank substrate, mask blank, exposure mask, mask blank substrate manufacturing method, and semiconductor manufacturing method
AssigneeHoya Corporation
InventorsMasaru Tanabe, Atsushi Kawaguchi, Hiroyuki Akagawa, Akihiro Kawahara
Life of this patent
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Abstract
In a mask blank substrate to be chucked by a mask stage of an exposure system, the flatness of a rectangular flatness measurement area excluding an area of 2 mm inward from an outer peripheral end surface on a main surface of the mask blank substrate on its side to be chucked by the mask stage is 0.6 μm or less, and at least three of four corner portions of the flatness measurement area each have a shape that rises toward the outer peripheral side.
Claims15
A mask blank substrate to be chucked by a mask stage of an exposure system, comprising:
- a rectangular flatness measurement area having four measurement area corners, said flatness measurement area excluding an area of 2 mm inward from an outer peripheral end surface on a main surface of the mask blank substrate on a side to be chucked by the mask stage, and
- a rectangular inner area having four inner area corners, said inner area excluding an area of 10 mm inward from the outer peripheral end surface,
- wherein flatness of the rectangular flatness measurement area is 0.6 μm or less, and
- each of at least three of the four measurement area corners is higher than a respective one of the corresponding inner area corner using, as a reference, a height of the inner area corner.
A mask blank substrate to be chucked by a mask stage of an exposure system, comprising:
- a rectangular flatness measurement area excluding an area of 2 mm inward from an outer peripheral end surface on a main surface of the mask blank substrate on a side to be chucked by the mask stage,
- an outer rectangular area having four outer area corners, said outer rectangular area excluding an area of 10 mm inward from the outer peripheral end surface, and
- an inner rectangular area having four inner area corners, said inner rectangular area excluding an area of 15 mm inward from the outer peripheral end surface,
- wherein flatness of the rectangular flatness measurement area is 0.6 μm or less, and
- at least one of the four outer area corners is higher than a corresponding one inner area corner using, as a reference, a height of the inner area corner.
Dependencies are inferred from the claim text.