A comparison of the optical projection lithography simulators in SAMPLE and PROLITH

This paper documents important algorithmic details not available in the open literature, and illustrates differences and similarities between the SAMPLE and PROLITH programs using representative lithography systems as examples. Numerical comparisons demonstrate that the aerial images calculated by SAMPLE and PROLITH are in generally good agreement. At high numerical resolution, the programs provide the same qualitative lithographic information, including latent images and edge profile results; however, significant degradation occurs at lower restorations. Adequate results are obtained using a vertical resolution smaller than one-twentieth of the theoretical standing-wave wavelength. Significant disagreement is found in the output of the post-exposure bake algorithms where SAMPLE predicts much lower standing-wave amplitude attenuation effects