Translator Disclaimer
23 March 2009 Polar Correction: new overlay control method for higher-order intra-field error dependent on the wafer coordinates
Author Affiliations +
Abstract
A new overlay control method called "Polar Correction" has been developed. In the 3x nm half-pitch generation and beyond, even in the case of using a high-end optical exposure system such as immersion lithography with NA 1.3 over, the overlay accuracy becomes the most critical issue, and the accuracy below 10nm is indispensable [1]. In view of the severe overlay accuracy required, the shot-to-shot intra-field overlay control cannot be disregarded in this generation. In particular, the shot-to-shot intra-field overlay error caused by the influence of evaporation heat has been added in the immersion exposure system. However, it is impossible to correct the shot-to-shot intra-field overlay error by the conventional overlay control method. Therefore, we have developed the new overlay control method called Polar Correction for higher-order intra-field error dependent on the wafer coordinates. In this paper, we explain our new overlay control method for higher-order intra-field error, and show the simulation data and the experimental data. We believe that Polar Correction corresponds to the generation below 10nm overlay accuracy.
© (2009) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Manabu Takakuwa, Keigo Toriumi, Nobuhiro Komine, Kazutaka Ishigo, Takuya Kono, Tetsuro Nakasugi, and Tatsuhiko Higashiki "Polar Correction: new overlay control method for higher-order intra-field error dependent on the wafer coordinates", Proc. SPIE 7272, Metrology, Inspection, and Process Control for Microlithography XXIII, 72720J (23 March 2009); https://doi.org/10.1117/12.813490
PROCEEDINGS
9 PAGES


SHARE
Advertisement
Advertisement
Back to Top