Research into characterization of wafer stepper systems has been done primarily by analyzing a series of wafer exposures. This method does not allow for easy separation of the effects of the exposure system and the resist processing system. In addition, determination of the transfer characteristics of projection lithographic lenses is typically done before the lens system is installed into the wafer stepper system. A method is presented which allows for the in-situ determination of the modulation transfer function. This method separates the processing effects from those of the exposure system. Scattered light from a polys il icon edge is shown to be in close agreement with the theoretical MTF as calculated by SAMPLE. Focus effects on the resultant MTF curves are demonstrated. A comparison between single and multiple scattering lines demonstrates that there is little difference in the MTF curves.

Library of Congress Subject Headings

Semiconductor wafers--Design--Analysis; Microlithography; Transfer functions

Publication Date


Document Type


Department, Program, or Center

Chester F. Carlson Center for Imaging Science (COS)


Smith, Bruce


Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: TK7874 .C374 1990


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