Abstract: Provided are optimized scatterometry techniques for evaluating a diffracting structure. In one embodiment, a method includes computing a finite-difference derivative of a field matrix with respect to first parameters (including a geometric parameter of the diffracting structure), computing an analytic derivative of the Jones matrix with respect to the field matrix, computing a derivative of the Jones matrix with respect to the first parameters, and computing a finite-difference derivative of the Jones matrix with respect to second parameters (including a non-geometric parameter). In one embodiment, a method includes generating a transfer matrix having Taylor Series approximations for elements, and decomposing the field matrix into two or more smaller matrices based on symmetry between the incident light and the diffracting structure.

Abstract: Provided are optimized scatterometry techniques for evaluating a diffracting structure. In one embodiment, a method includes computing a finite-difference derivative of a field matrix with respect to first parameters (including a geometric parameter of the diffracting structure), computing an analytic derivative of the Jones matrix with respect to the field matrix, computing a derivative of the Jones matrix with respect to the first parameters, and computing a finite-difference derivative of the Jones matrix with respect to second parameters (including a non-geometric parameter). In one embodiment, a method includes generating a transfer matrix having Taylor Series approximations for elements, and decomposing the field matrix into two or more smaller matrices based on symmetry between the incident light and the diffracting structure.

Abstract: A profile model to characterize a structure to be examined using optical metrology is evaluated by displaying a set of profile parameters that characterizes the profile model. Each profile parameter has a range of values for the profile parameter. For each profile parameter having a range of values, an adjustment tool is displayed for selecting a value for the profile parameter within the range of values. A measured diffraction signal, which was measured using an optical metrology tool, is displayed. A simulated diffraction signal, which was generated based on the values of the profile parameters selected using the adjustment tools for the profile parameters, is displayed. The simulated diffraction signal is overlaid with the measured diffraction signal.

Abstract: A system to process requests for wafer structure profile determination from optical metrology measurements off a plurality of structures formed on one or more wafer includes a diffraction signal processor, a diffraction signal distributor, and a plurality of profile search servers. The diffraction signal processor is configured to obtain a plurality of measured diffraction signals of the plurality of structures. The diffraction signal distributor is coupled to the diffraction signal processor. The diffraction signal processor is configured to transmit the plurality of measured diffraction signals to the diffraction signal distributor. The plurality of profile search servers is coupled to the diffraction signal distributor. The diffraction signal distributor is configured to distribute the plurality of measured diffraction signals to the plurality of profile search servers.

Abstract: One or more profile parameters of a structure fabricated on a wafer in a wafer application are determined by developing a correlation between a set of profile models and one or more key profile shape variables. The wafer application has one or more process steps and one or more process parameters. Each profile model is defined using a set of profile parameters to characterize the shape of the structure. Different sets of profile parameters define the profile models in the set. The one or more key profile shape variables include one or more profile parameters or one or more process parameters. A value of at least one key profile shape variable of the process step of the wafer application to be used in fabricating the structure is determined. One profile model is selected from the set of profile models based on the determined correlation and the value of the at least one determined key profile shape variable.

Abstract: A process step in fabricating a structure on a wafer in a wafer application having one or more process steps and one or more process parameters is controlled by determining a correlation between a set of profile models and one or more key profile shape variables. Each profile model is defined using a set of profile parameters to characterize the shape of the structure. Different sets of profile parameters define the profile models in the set. The one or more key profile shape variables include one or more profile parameters or one or more process parameters. One profile model is selected from the set of profile models based on the correlation and a value of at least one key profile shape variable of the process of the wafer application to be used in fabricating the structure. The structure is fabricated in a first fabrication process cluster using the process step and the value of the at least one key profile shape variable. A measured diffraction signal is obtained off the structure.

Abstract: To manage data flow in generating profile models for use in optical metrology, a project data object is created. A first profile model data object is created. The first profile model data object corresponds to a first profile model defined using profile parameters. A version number is associated with the first profile model data object. The first profile model data object is linked with the project data object. At least a second profile model data object is created. The second profile model data object corresponds to a second profile model defined using profile parameters. The first and second profile models are different. Another version number is associated with the second profile model data object. The second profile model data object is linked with the project data object. The project data object, the first profile model data object, and the second profile model data object are stored.

Abstract: To manage data flow in generating different signal formats for use in optical metrology, a project data object is created. A first option data object is created. The first option data object has a set of signal parameters. Different settings of the set of signal parameters correspond to different signal formats for diffraction signals. A version number is associated with the first option data object. The first option data object is linked with the project data object. At least a second option data object is created. The second option data object has a set of signal parameters. Different settings of the set of signal parameters correspond to different signal formats for diffraction signals. The set of signal parameters of the first option data object and the set of signal parameters of the second option data object are set differently. Another version number is associated with the second option data object. The second option data object is linked with the project data object.

Abstract: In processing requests for wafer structure profile determination from optical metrology measurements, a plurality of measured diffraction signal of a plurality of structures formed on one or more wafers is obtained. The plurality of measured diffraction signals is distributed to a plurality of instances of a profile search module. The plurality of instances of the profile search model is activated in one or more processing threads of one or more computer systems. The plurality of measured diffraction signals is processed in parallel using the plurality of instances of the profile search module to determine profiles of the plurality of structures corresponding to the plurality of measured diffraction signals.

Abstract: A system to process requests for wafer structure profile determination from optical metrology measurements off a plurality of structures formed on one or more wafer includes a diffraction signal processor, a diffraction signal distributor, and a plurality of profile search servers. The diffraction signal processor is configured to obtain a plurality of measured diffraction signals of the plurality of structures. The diffraction signal distributor is coupled to the diffraction signal processor. The diffraction signal processor is configured to transmit the plurality of measured diffraction signals to the diffraction signal distributor. The plurality of profile search servers is coupled to the diffraction signal distributor. The diffraction signal distributor is configured to distribute the plurality of measured diffraction signals to the plurality of profile search servers.

Abstract: In generating a profile model to characterize a structure to be examined using optical metrology, a view canvas is displayed, with the profile model being generated displayed in the view canvas. A profile shape palette is displayed adjacent to the view canvas. A plurality of different profile shape primitives is displayed in the profile shape palette. Each profile shape primitive in the profile shape palette is defined by a set of profile parameters. When a user selects a profile shape primitive from the profile shape palette, drags the selected profile shape primitive from the profile shape palette, and drops the selected profile shape primitive into the view canvas, the selected profile shape primitive is incorporated into the profile model being generated and displayed in the view canvas.

Abstract: A profile model to characterize a structure to be examined using optical metrology is evaluated by displaying a set of profile parameters that characterizes the profile model. Each profile parameter has a range of values for the profile parameter. For each profile parameter having a range of values, an adjustment tool is displayed for selecting a value for the profile parameter within the range of values. A measured diffraction signal, which was measured using an optical metrology tool, is displayed. A simulated diffraction signal, which was generated based on the values of the profile parameters selected using the adjustment tools for the profile parameters, is displayed. The simulated diffraction signal is overlaid with the measured diffraction signal.

Abstract: Methods for improving the manufacture of objects made by layered manufacturing techniques through improved tool path generation. A vertex improvement aspect improves tool paths used to form vertices. Outer perimeter vertices can be improved by automatically creating an outer boundary reflecting the design intent to have material extending to the perimeter vertex. The outer boundary can be used as a contour tool path or as a limit to travel by raster tool paths. Boundary vertices within parts can be improved by extending more internal boundary vertices outward toward enclosing vertices, thereby eliminating some internal voids. Contour boundaries near outer perimeter corners can be better defined by extending outward a contour tool path toward the corners. Narrow regions between combinations of outer and/or inner perimeters can be filled through improved tool paths. Layer regions near inner voids can receive consistent filling through an improved raster tool path method.