US 12,243,768 B2
Substrate holder for use in a lithographic apparatus and a device manufacturing method
Johannes Josephus Maassen, Waalre (NL); André Schreuder, Eindhoven (NL); and Herman Marquart, Eindhoven (NL)
Assigned to ASML NETHERLANDS B.V., Veldhoven (NL)
Appl. No. 17/421,085
Filed by ASML NETHERLANDS B.V., Veldhoven (NL)
PCT Filed Dec. 13, 2019, PCT No. PCT/EP2019/085167
§ 371(c)(1), (2) Date Jul. 7, 2021,
PCT Pub. No. WO2020/151878, PCT Pub. Date Jul. 30, 2020.
Claims priority of application No. 19153181 (EP), filed on Jan. 23, 2019.
Prior Publication US 2022/0115260 A1, Apr. 14, 2022
Int. Cl. H01L 21/687 (2006.01); G03F 7/00 (2006.01)
CPC H01L 21/6875 (2013.01) [G03F 7/70783 (2013.01); G03F 7/70825 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A substrate holder for use in a lithographic apparatus and configured to support a substrate, the substrate holder comprising:
a main body having a main body surface;
a plurality of burls projecting from the main body surface and each having a distal end surface which substantially conforms to a support plane and is configured for supporting the substrate; and
an edge seal projecting from the main body surface and extending around the plurality of burls so as to restrict gas flow when a substrate is held by the substrate holder; wherein:
the edge seal is spaced apart from the plurality of burls so as to define a gap between the edge seal and the plurality of burls, the gap having a gap width that is greater than or equal to about 75% of a pitch of the plurality of burls;
the plurality of burls comprises a first group of burls and a second group of burls, the second group of burls surrounding the first group of burls; and
the stiffness in a direction perpendicular to the support plane per unit area of the second group of burls is greater than or equal to about 150% of the stiffness in the direction perpendicular to the support plane per unit area of the first group of burls.