US 11,921,435 B2
Lithographic systems and methods of operating the same
Jeroen de Boeij, 's-Hertogenbosch (NL); and Mikhail Yurievich Loktev, Valkenswaard (NL)
Assigned to Kulicke & Soffa Liteq B.V., Eindhoven (NL)
Filed by Kulicke & Soffa Liteq B.V., Eindhoven (NL)
Filed on Dec. 5, 2022, as Appl. No. 18/074,639.
Application 18/074,639 is a continuation of application No. 17/600,956, granted, now 11,550,232, previously published as PCT/EP2020/055074, filed on Feb. 26, 2020.
Claims priority of provisional application 62/831,381, filed on Apr. 9, 2019.
Prior Publication US 2023/0094792 A1, Mar. 30, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. G03F 7/00 (2006.01)
CPC G03F 7/70875 (2013.01) [G03F 7/70066 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of operating a lithographic system, the method comprising the steps of:
(a) supporting a workpiece using a support structure of the lithographic system;
(b) projecting an image on the workpiece using radiation from a radiation source of the lithographic system;
(c) positioning a reticle between the radiation source and the workpiece; and
(d) positioning a mask within 100 mm of the reticle along a z-axis of the lithographic system, the mask being configured to block radiation from the radiation source, the mask including a body portion and a radiation absorbing coating applied to at least a portion of an external surface of the body portion, wherein the radiation absorbing coating is an inorganic black coating.