| CPC H01L 21/7684 (2013.01) [H01L 21/32115 (2013.01); H01L 21/67253 (2013.01)] | 9 Claims |

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1. A superstrate for planarizing a formable material on a substrate, wherein the superstrate is held by a chuck comprising a plurality of lands defining a central zone and a peripheral zone surrounding the central zone, the superstrate comprising:
a first side and a second side opposite to the first side;
an outermost edge; and
a mesa formed on the first side, wherein an edge of the mesa is positioned inside from the outermost edge, and wherein the mesa has a planar contact surface to be in contact with the formable material on the substrate;
wherein the second side has a central portion and a peripheral portion surrounding the central portion, and the peripheral portion includes a surface depressed in such a way as to form a step with respect to the central portion, and
wherein the depressed surface of the superstrate held by the chuck has a contact surface to be in contact with an outer land among the plurality of lands of the chuck.
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