| 摘要 |
Optimized dose assignments are determined for each portion of a layout by utilizing an improved proximity function and additional dose correction functions in performing a short range proximity effect correction. The optimized dose assignments are determined to minimize critical dimension (CD) deviations and maintain CD linearity across different feature sizes. The improved proximity function and additional dose correction functions are determined by calibration based on experimental CD measurements of test designs. The improved proximity function includes a sum of more than two Gaussian functions, each having an associated effect range and an associated weight, wherein one or more of the associated weights may be negative. The additional dose correction functions include an iso-dense bias correction function and a dose evaluation point displacement function for line end shortening correction. The short range proximity effect correction results are provided as input to a subsequent long range proximity correction.
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