Abstract: The X, Y and Rz positions of a mask stage are measured using two optical encoder-reading heads measuring displacements of respective grid gratings mounted on the mask stage. The grid gratings are preferably provided on cut-away portions of the mask table so as to be coplanar with the pattern on the mask itself. Measurements of the table position in the other degrees of freedom can be measured with capacitative or optical height sensors.
Abstract: An immersion lithography apparatus comprises a temperature controller configured to adjust a temperature of a projection system, a substrate and a liquid towards a common target temperature. Controlling the temperature of these elements and reducing temperature gradients may improve imaging consistency and general lithographic performance. Measures to control the temperature may include controlling the immersion liquid flow rate and liquid temperature, for example, via a feedback circuit.
Type:
Application
Filed:
July 14, 2004
Publication date:
March 3, 2005
Applicant:
ASMIL NETHERLANDS B.V.
Inventors:
Bob Streefkerk, Antonius Maria Derksen, Joeri Lof, Klaus Simon, Alexander Straaijer
Abstract: A lithographic mask is placed in a chamber which is then sealed. The gas pressure in the chamber is reduced to dislodge contaminant particles on the mask surface.
© 2025 Justia
