Effect of exposure tool illumination settings and objective numerical aperture on the standing wave period within photoresist

Stewart A. Robertson; Frank T.G.M. Linskens; Charles R. Szmanda; Kevin J. Dempsey

doi:10.1117/12.354301

Translator Disclaimer

26 July 1999 Effect of exposure tool illumination settings and objective numerical aperture on the standing wave period within photoresist

Stewart A. Robertson, Frank T.G.M. Linskens, Charles R. Szmanda, Kevin J. Dempsey

Author Affiliations +

Proceedings Volume 3679, Optical Microlithography XII; (1999) https://doi.org/10.1117/12.354301
Event: Microlithography '99, 1999, Santa Clara, CA, United States

Abstract

During the exposure of photoresist, standing waves form within the film, modulating the intensity of the illumination with depth in a sinusoidal fashion. Significant changes in the standing wave period are observed when the exposure tool numerical and illumination settings are altered. These changes are explained and demonstrated by means of both experimentation and lithography simulation for conventional and annular illumination. A function is derived which fully characterizes standing wave extrema separation in terms of numerical aperture and partial coherent for conventional illumination. It is shown that when extrema separation is normalized by a factor of (lambda) /4n that the resulting function is independent of (lambda) and exposure tool magnification ratio, but is sensitive to changes in n. Although not fully characterized, the effect of annular illumination on extrema separation is explored and some key aspects of the behavior are identified.

Citation Download Citation

Stewart A. Robertson, Frank T.G.M. Linskens, Charles R. Szmanda, and Kevin J. Dempsey "Effect of exposure tool illumination settings and objective numerical aperture on the standing wave period within photoresist", Proc. SPIE 3679, Optical Microlithography XII, (26 July 1999); https://doi.org/10.1117/12.354301

ACCESS THE FULL ARTICLE