Abstract: A system for determining a sample map for alignment measurements includes a metrology tool and a controller. The controller defines a full sampling map including a plurality of measurement locations. The controller directs the metrology tool to measure alignment at each measurement location of the full sampling map for a plurality of samples to generate a reference alignment dataset, generates candidate sampling maps, each being a subset of the full sampling map. The controller may further estimate alignment as a function of location based on the two or more candidate sampling maps at each measurement location of the full sampling map, and determine a working sampling map by comparing the estimated alignment to the reference alignment dataset and selecting the candidate sampling map having a smallest number of alignment estimates exceeding a selected tolerance.

Abstract: Methods and systems for providing overlay corrections are provided. A method may include: selecting an overlay model configured to perform overlay modeling for a wafer; obtaining a first set of modeled results from the overlay model, the first set of modeled results indicating adjustments applicable to a plurality of term coefficients of the overlay model; calculating a significance matrix indicating the significance of the plurality of term coefficients; identifying at least one less significant term coefficient among the plurality of term coefficients based on the calculated significance matrix; obtaining a second set of modeled results from the overlay model, the second set of modeled results indicating adjustments applicable to the plurality of term coefficients except for the identified at least one less significant term coefficient; and providing the second set of modeled results to facilitate overlay correction.

Abstract: A semiconductor tool includes an illumination source to generate an illumination beam, one or more illumination optical elements to direct a portion of the illumination beam to a sample, a detector, one or more collection optical elements to direct radiation emanating from the sample to the detector, and a controller communicatively coupled to the detector. The controller is configured to measure alignment at a plurality of locations across the sample to generate alignment data, select an analysis area for alignment zone determination, divide the analysis area into two or more alignment zones having different alignment signatures; model the alignment data of at least a first alignment zone of the two or more alignment zones using a first alignment model, and model the alignment data of at least a second alignment zone of the two or more alignment zones using a second alignment model different than the first alignment model.

Abstract: A system for determining a sample map for alignment measurements includes a metrology tool and a controller. The controller defines a full sampling map including a plurality of measurement locations. The controller directs the metrology tool to measure alignment at each measurement location of the full sampling map for a plurality of samples to generate a reference alignment dataset, generates candidate sampling maps, each being a subset of the full sampling map. The controller may further estimate alignment as a function of location based on the two or more candidate sampling maps at each measurement location of the full sampling map, and determine a working sampling map by comparing the estimated alignment to the reference alignment dataset and selecting the candidate sampling map having a smallest number of alignment estimates exceeding a selected tolerance.

Abstract: A semiconductor tool includes an illumination source to generate an illumination beam, one or more illumination optical elements to direct a portion of the illumination beam to a sample, a detector, one or more collection optical elements to direct radiation emanating from the sample to the detector, and a controller communicatively coupled to the detector. The controller is configured to measure alignment at a plurality of locations across the sample to generate alignment data, select an analysis area for alignment zone determination, divide the analysis area into two or more alignment zones having different alignment signatures; model the alignment data of at least a first alignment zone of the two or more alignment zones using a first alignment model, and model the alignment data of at least a second alignment zone of the two or more alignment zones using a second alignment model different than the first alignment model.

Abstract: Methods and systems for providing overlay corrections are provided. A method may include: selecting an overlay model configured to perform overlay modeling for a wafer; obtaining a first set of modeled results from the overlay model, the first set of modeled results indicating adjustments applicable to a plurality of term coefficients of the overlay model; calculating a significance matrix indicating the significance of the plurality of term coefficients; identifying at least one less significant term coefficient among the plurality of term coefficients based on the calculated significance matrix; obtaining a second set of modeled results from the overlay model, the second set of modeled results indicating adjustments applicable to the plurality of term coefficients except for the identified at least one less significant term coefficient; and providing the second set of modeled results to facilitate overlay correction.