Need for accuracy, precision, speed and sophistication in metrology has increased tremendously over the past few years. Lithography performance will increasingly depend on post patterning metrology and this dependency will be heavily accelerated by technology shrinkage. These requirements will soon become so stringent that the current metrology capabilities may not be sufficient to support these near future needs. Accuracy and precision requirements approaching well into sub-nanometer range while the demand for increase in sampling also continues, triggering the need for a new technology in this area. In this technical presentation the authors would like to evaluate such technology that has the potential to support the future needs. Extensive data collection and tests are ongoing for both CD and overlay. Data on first order diffraction based overlay shows unprecedented measurement precision. The levels of precision are so low that for evaluation special methods has been developed and tested. In this paper overlay measurement method and data will be discussed, as well as applicability for future nodes and novel lithography techniques. CD data will be reported in the future technical publications.

Date Published: 1 December 2008
PDF: 6 pages
Proc. SPIE 7140, Lithography Asia 2008, 71400N (1 December 2008); doi: 10.1117/12.807998

Published in SPIE Proceedings Vol. 7140:
Lithography Asia 2008
Alek C. Chen; Burn Lin; Anthony Yen, Editor(s)