With the implementation of multi-patterning ArF-immersion for sub 20nm integrated circuits (IC), advances in equipment monitoring and control are needed to support on-wafer yield performance. These in-situ equipment monitoring improvements, along with advanced litho-cell corrections based on on-wafer measurements, enable meeting stringent overlay and CD control requirements for advanced lithography patterning. The importance of light-source performance on lithography pattering (CD and overlay) has been discussed in previous publications.^[1-3] Recent developments of Cymer ArF light-source metrology and on-board monitoring enable end-users to detect, for each exposed wafer, changes in the near-field and far-field spatial profiles and polarization performance, ^[4-6] in addition to the key ‘optical’ scalar parameters, such as bandwidth, wavelength and energy. The major advantage of this capability is that the key performance metrics are sampled at rates matched to wafer performance, e.g. every exposure field across the wafer, which is critical for direct correlation with on-wafer performance for process control and excursion detection.

Date Published: 4 April 2014
PDF: 10 pages
Proc. SPIE 9052, Optical Microlithography XXVII, 905228 (4 April 2014); doi: 10.1117/12.2047449

Published in SPIE Proceedings Vol. 9052:
Optical Microlithography XXVII
Kafai Lai; Andreas Erdmann, Editor(s)