Prediction of multiple-feature effects in plasma etching

Charging and topography evolution simulations during plasma etching of dense line-and-space patterns reveal that multiple-feature effects influence critically the etch profile characteristics of the various lines. By including neighboring lines, the simulation predicts a peculiar notching behavior, where the extent of notching varies with the location of the line. Feature-scale modeling can no longer be focused on individual features alone; “adjacency” effects are crucial for understanding and predicting the outcome of etching experiments at reduced device dimensions.