Abstract: Methods for the determination of center of focus and process control for a lithographic tool. Diffraction signatures are obtained from a plurality of diffraction structures located within multiple different focus setting fields. Variability of diffraction signatures with each field are determined, by direct analysis or comparison to a library. The variation or uniformity may be represented by any measure, including the standard deviation or the range of values of a chosen feature of a library of theoretical diffraction structures or the variability or uniformity of the diffraction signatures themselves, such as by RMS difference or intensity range. The methods may be used for process control and monitoring of focus drift by determining intra-field variation of diffraction signatures of multiple diffraction structures in a series of wafers.

Abstract: Methods for determination of parameters in lithographic devices and applications by cross-section analysis of scatterometry models, including determination of center of focus in lithography devices and applications. Control methods are provided for process control of center of focus in lithography devices utilizing cross-section analysis.

Abstract: Methods for the determination of center of focus and process control for a lithographic tool. Diffraction signatures are obtained from a plurality of diffraction structures located within multiple different focus setting fields. Variability of diffraction signatures with each field are determined, by direct analysis or comparison to a library. The variation or uniformity may be represented by any measure, including the standard deviation or the range of values of a chosen feature of a library of theoretical diffraction structures or the variability or uniformity of the diffraction signatures themselves, such as by RMS difference or intensity range. The methods may be used for process control and monitoring of focus drift by determining intra-field variation of diffraction signatures of multiple diffraction structures in a series of wafers.

Abstract: Methods for determination of parameters in lithographic devices and applications by cross-section analysis of scatterometry models, including determination of center of focus in lithography devices and applications. Control methods are provided for process control of center of focus in lithography devices utilizing cross-section analysis.

Abstract: Methods for metrology of undercut multi-layer diffracting structures, utilizing diffraction signature analysis obtained by means of a radiation-based tool, wherein simulated diffraction signals are generated based on models of undercut multi-layer structures. In one method, comparison to a library is employed. In another method, regression analysis is employed. The undercut parameters, including critical dimension and materials factors, can be altered in the models.

Abstract: Methods for determination of parameters in lithographic devices and applications by diffraction signature difference analysis, including determination of center of focus in lithography devices and applications. Latent image analysis may be employed with exposed but undeveloped lithographic substrates. Control methods are provided for process control of center of focus in lithography devices utilizing diffraction signature difference analysis.

Abstract: Methods for determination of parameters in lithographic devices and applications by diffraction signature difference analysis, including determination of center of focus in lithography devices and applications. Latent image analysis may be employed with exposed but undeveloped lithographic substrates. Control methods are provided for process control of center of focus in lithography devices utilizing diffraction signature difference analysis.

Abstract: The present invention provides methods for determination of parameters in lithographic devices and applications by diffraction signature difference analysis, including determination of center of focus in lithography devices and applications.