A theoretical investigation of the effects of imaging a patterned rough surface through focus is performed, and the statistics of the image plane irradiance, as well as those of the image pattern printed in a threshold-type photoresist, are investigated. It is demonstrated that the line edge roughness in the printed image increases substantially as the image plane is moved out of focus, for both fully and partially coherent optical systems. Furthermore, the increase in line edge roughness occurs in what is considered to be an otherwise acceptable depth of focus for an ideal system.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics