METHOD AND SYSTEM TO PREDICT LITHOGRAPHY FOCUS ERROR USING SIMULATED OR MEASURED TOPOGRAPHY

摘要

A method and system to predict lithography focus error using chip topography data is disclosed. The chip topography data may be measured or simulated topography data. A plane is best fitted to the topography data, and residuals are computed. The residuals are then used to make a prediction regarding the focus error. The density ratio of metal to dielectric may also be used as a factor in determining the predicted focus error.