Mask blank substrate set and mask blank set
AssigneeHoya Corporation
InventorMasaru Tanabe
Life of this patent
Estimating the term…
Abstract
A substrate set is a mask blank substrate set including a plurality of substrates each for use in a mask blank for producing a photomask to be chucked on a mask stage of an exposure apparatus. In each of the substrates in the mask blank substrate set, a main surface, on the side where a thin film for forming a transfer pattern is to be formed, has a convex shape being relatively high at its center and relatively low at its peripheral portion. In each substrate, the flatness in a 142 mm square area, including a central portion, of the main surface is 0.3 μm or less and the difference upon fitting to a reference main surface of a reference substrate is 40 nm or less.
Claims8
A mask blank substrate set comprising a plurality of substrates each for use in a mask blank for producing a photomask to be chucked on a mask stage of an exposure apparatus,
- wherein, in each of the substrates in said mask blank substrate set, a main surface, on a side where a thin film for forming a transfer pattern is to be formed, has a convex shape being relatively high at its center and relatively low at its peripheral portion and has a flatness of 0.3 μm or less in a 142 mm square area, including a central portion, of said main surface and a difference upon performing fitting in a 132 mm square area, including the central portion, of said main surface with respect to a reference main surface of a reference substrate is 40 nm or less.
A mask blank set comprising:
- preparing a mask blank substrate set comprising a plurality of substrates each for use in a mask blank for producing a photomask to be chucked on a mask stage of an exposure apparatus, wherein, in each of the substrates in said mask blank substrate set, a main surface, on a side where a thin film for forming a transfer pattern is to be formed, has a convex shape being relatively high at its center and relatively low at its peripheral portion and has a flatness of 0.3 μm or less in a 142 mm square area, including a central portion, of said main surface and a difference upon performing fitting in a 132 mm square area, including the central portion, of said main surface with respect to a reference main surface of a reference substrate is 40 nm or less;
- and
- preparing a set of mask blanks manufactured by forming said thin film on the main surface of each of the substrates in said mask blank substrate set.
A photomask set comprising:
- preparing a mask blank substrate set comprising a plurality of substrates each for use in a mask blank for producing a photomask to be chucked on a mask stage of an exposure apparatus, wherein, in each of the substrates in said mask blank substrate set, a main surface, on a side where a thin film for forming a transfer pattern is to be formed, has a convex shape being relatively high at its center and relatively low at its peripheral portion and has a flatness of 0.3 μm or less in a 142 mm square area, including a central portion, of said main surface and a difference upon performing fitting in a 132 mm square area, including the central portion, of said main surface with respect to a reference main surface of a reference substrate is 40 nm or less;
- preparing a set of mask blanks manufactured by forming said thin film on the main surface of each of the substrates in said mask blank substrate set;
- and
- preparing a set of photomasks manufactured by patterning said thin film of each of said mask blanks in the set.
A semiconductor device manufacturing method comprising:
- preparing a mask blank substrate set comprising a plurality of substrates each for use in a mask blank for producing a photomask to be chucked on a mask stage of an exposure apparatus, wherein, in each of the substrates in said mask blank substrate set, a main surface, on a side where a thin film for forming a transfer pattern is to be formed, has a convex shape being relatively high at its center and relatively low at its peripheral portion and has a flatness of 0.3 μm or less in a 142 mm square area, including a central portion, of said main surface and a difference upon performing fitting in a 132 mm square area, including the central portion, of said main surface with respect to a reference main surface of a reference substrate is 40 nm or less;
- preparing a set of mask blanks manufactured by forming said thin film on the main surface of each of the substrates in said mask blank substrate set;
- preparing a set of photomasks manufactured by forming a transfer pattern in said thin film of each of said mask blanks in the set;
- and
- transferring, using said set of photomasks, the transfer patterns of said photomasks in turn onto a semiconductor substrate by photolithography.
Dependencies are inferred from the claim text.