Numerics for Control & Identification (N4CI)


Delft Center for Systems and Control

Delft University of Technology

Adaptive Optics for EUV lithography (Funding: AgentschapNL, Peaks in the Delta)

Applicants: Dr. Niek Doelman (TNO, project leader)
Prof. Rob Munnig Schmidt (TU Delft)
Ir. Jo Spronck (TU Delft)
Prof. Paul Urbach (TU Delft)
Prof. Maarten Steinbuch (Eindhoven Univ.)
Dr. Nick Rosielle (Eindhoven Univ.)
Prof. Michel Verhaegen (TU Delft)
Researchers: Alessandro Polo (TU Delft)
Simon Ravensbergen (Eindhoven Univ.)
Rudolf Saathof (TU Delft)
Aleksandar Haber (TU Delft)
Project outline:

Because of their very short wavelength and high power illumination, EUV lithography systems are sensitive to variations in heat loading. The goal of this project is to compensate for heat induced aberrations in the optics of EUV lithography systems.

EUV lithography
Schematic of an EUV lithography system.

One of the subproblems, that is researched in the N4CI group by Aleksandar Haber, is the problem of determing the optical disturbances during exposure. Only between two exposures some (limited) measurements can be made, from which the evolution of the disturbance during exposure need to be determined such that it can be compensated for. Because the high accuracy and the large number of degrees of freedom in the disturbance, distributed modeling and prediction techniques are needed.

prediction
The disturbance during exposure will be predicted from the (past) measurements.