2D patterns for the latest technology nodes are not predicted well enough using 1D features/metrology - High resolution, accurate 2D contours from actual wafer prints are needed to verify and validate today's designs.
- Simulations are absolutely necessary as a first step but insufficent in preventing all 2D problems.
- Simulation-only validation can only point out the hotspot that are already expected by the models. As has been said "all models are wrong, some are useful".
- High resolution CD-SEMs are required for accuracy and precision, but the field of view (FOV) is too limited to capture all of the effects/important features.
- Crude alignment and overlap of CD-SEM images does not produce seemless contours. Ragged or inaccurate contours are not of much value.
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