US 12,339,592 B2
Method for thermo-mechanical control of a heat sensitive element and device for use in a lithographic production process
Victor Sebastiaan Dolk, Eindhoven (NL); Koos Van Berkel, Waalre (NL); and Mauritius Gerardus Elisabeth Schneiders, Eindhoven (NL)
Assigned to ASML Netherlands B.V., Veldhoven (NL)
Appl. No. 18/010,637
Filed by ASML Netherlands B.V., Veldhoven (NL)
PCT Filed Jun. 2, 2021, PCT No. PCT/EP2021/064753
§ 371(c)(1), (2) Date Dec. 15, 2022,
PCT Pub. No. WO2022/002519, PCT Pub. Date Jan. 6, 2022.
Claims priority of application No. 20183453 (EP), filed on Jul. 1, 2020.
Prior Publication US 2023/0229090 A1, Jul. 20, 2023
Int. Cl. G03F 7/00 (2006.01)
CPC G03F 7/70891 (2013.01) [G03F 7/70504 (2023.05); G03F 7/70525 (2013.01); G03F 7/706 (2013.01)] 25 Claims
OG exemplary drawing
 
1. A method for thermo-mechanical control of a heat sensitive element subject to a heat load, comprising:
providing a non-linear thermo-mechanical model of the heat sensitive element describing a dynamical relationship between the heat load on the heat sensitive element and deformation of the heat sensitive element,
at a first time step, calculating, for each of a plurality of future time steps including a next time step, a feedforward control signal on the basis of an optimization calculation of the non-linear model, the optimization calculation configured to optimize the deformation of the heat sensitive element throughout a prediction horizon corresponding to the plurality of future time steps, taking into account constraints on actuation limits of the heater,
at the next time step, providing an actuation signal to a heater, wherein the actuation signal is at least partially based on the control signal calculated at the first time step, and
heating the heat sensitive element by the heater on the basis of the actuation signal.