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: An apparatus to examine a patterned structure formed on a semiconductor wafer using an optical metrology model includes a fabrication system and a metrology processor. The fabrication system includes a fabrication cluster, metrology cluster, metrology model optimizer, and real time profile estimator. The fabrication cluster is configured to process wafers, the wafers having patterned and unpatterned structures. The patterned structures have underlying film thicknesses, critical dimension, and profile. The metrology cluster includes one or more optical metrology devices. The metrology cluster is configured to measure diffraction signals off the patterned and the unpatterned structures. The metrology model optimizer is configured to optimize an optical metrology model of the patterned structure using one or more measured diffraction signals off the patterned structure and with floating profile parameters, material refraction parameters, and metrology device parameters.

Abstract: A system for examining a patterned structure formed on a semiconductor wafer using an optical metrology model includes a first fabrication cluster, a metrology cluster, an optical metrology model optimizer, and a real time profile estimator. The first fabrication cluster configured to process a wafer, the wafer having a first patterned and a first unpatterned structure. The first patterned structure has underlying film thicknesses, critical dimension, and profile. The metrology cluster including one or more optical metrology devices coupled to the first fabrication cluster. The metrology cluster is configured to measure diffraction signals off the first patterned and the first unpatterned structure. The metrology model optimizer is configured to optimize an optical metrology model of the first patterned structure using one or more measured diffraction signals off the first patterned structure and with floating profile parameters, material refraction parameters, and metrology device parameters.

Abstract: To examine a patterned structure formed on a semiconductor wafer using an optical metrology model, an optical metrology model is created for the patterned structure. The optical metrology model has profile parameters, material refraction parameters, and metrology device parameters. Ranges of values for the profile parameters, material refraction parameters, and metrology device parameters are defined. One or more measured diffraction signals of the patterned structure are obtained. The optical metrology model is optimized to obtain an optimized optical metrology model using the defined ranges of values defined and the one or more obtained measured diffraction signals of the patterned structure. For at least one parameter from amongst the material refraction parameters and the metrology device parameters, the at least one parameter is set to a fixed value within the range of values for the at least one parameter.

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: The accuracy of a library of simulated-diffraction signals for use in optical metrology of a structure formed on a wafer is evaluated by utilizing an identity relationship inherent to simulated diffraction signals. Each simulated diffraction signal contains at least one set of four reflectivity parameters for a wavelength and/or angle of incidence. One of the four reflectivity parameters is selected. A value for the selected reflectivity parameter is determined using the identity relationship and values of the remaining three reflectivity parameters. The determined value for the selected reflectivity parameter is compared to the value in the obtained set of four reflectivity parameters to evaluate and improve the accuracy of the library. The identity relationship can also be used to reduce the data storage in a library.

Abstract: A structure formed on a semiconductor wafer is examined by obtaining a first diffraction signal measured from the structure using an optical metrology device. A first profile is obtained from a first machine learning system using the first diffraction signal obtained as an input to the first machine learning system. The first machine learning system is configured to generate a profile as an output for a diffraction signal received as an input. A second profile is obtained from a second machine learning system using the first profile obtained from the first machine learning system as an input to the second machine learning system. The second machine learning system is configured to generate a diffraction signal as an output for a profile received as an input. The first and second profiles include one or more parameters that characterize one or more features of the structure.

Abstract: To determine one or more features of an in-die structure on a semiconductor wafer, a correlation is determined between one or more features of a test structure to be formed on a test pad and one or more features of a corresponding in-die structure. A measured diffraction signal measured off the test structure is obtained. One or more features of the test structure are determined using the measured diffraction signal. The one or more features of the in-die structure are determined based on the one or more determined features of the test structure and the determined correlation.

Abstract: The accuracy of a library of simulated-diffraction signals for use in optical metrology of a structure formed on a wafer is evaluated by utilizing an identity relationship inherent to simulated diffraction signals. Each simulated diffraction signal contains at least one set of four reflectivity parameters for a wavelength and/or angle of incidence. One of the four reflectivity parameters is selected. A value for the selected reflectivity parameter is determined using the identity relationship and values of the remaining three reflectivity parameters. The determined value for the selected reflectivity parameter is compared to the value in the obtained set of four reflectivity parameters to evaluate and improve the accuracy of the library. The identity relationship can also be used to reduce the data storage in a library.

Abstract: A structure formed on a wafer can be examined by directing an incident pulse at the structure, the incident pulse being a sub-picosecond optical pulse. A diffraction pulse resulting from the incident pulse diffracting from the structure is measured. A characteristic of the profile of the structure is then determined based on the measured diffraction pulse.

Abstract: An optical metrology system includes a photometric device with a source configured to generate and direct light onto a structure, and a detector configured to detect light diffracted from the structure and to convert the detected light into a measured diffraction signal. A processing module of the optical metrology system is configured to receive the measured diffraction signal from the detector to analyze the structure. The optical metrology system also includes a generic interface disposed between the photometric device and the processing module. The generic interface is configured to provide the measured diffraction signal to the processing module using a standard set of signal parameters. The standard set of signal parameters includes a reflectance parameter chat characterizes the change in intensity of light when reflected on the structure and a polarization parameter that characterizes the change in polarization states of light when reflected on the structure.

Abstract: A weighting function is obtained to enhance measured diffraction signals used in optical metrology. To obtain the weighting function, a measured diffraction signal is obtained. The measured diffraction signal was measured from a site on a wafer using a photometric device. A first weighting function is defined based on noise that exists in the measured diffraction signal. A second weighting function is defined based on accuracy of the measured diffraction signal. A third weighting function is defined based on sensitivity of the measured diffraction signal. A fourth weighting function is defined based on one or more of the first, second, and third weighting functions.

Abstract: Specific wavelengths to use in optical metrology of an integrated circuit can be selected using one or more selection criteria and termination criteria. Wavelengths are selected using the selection criteria, and the selection of wavelengths is iterated until the termination criteria are met.

Abstract: Metrology data from a semiconductor treatment system is transformed using multivariate analysis. In particular, a set of metrology data measured or simulated for one or more substrates treated using the treatment system is obtained. One or more essential variables for the obtained set of metrology data is determined using multivariate analysis. A first metrology data measured or simulated for one or more substrates treated using the treatment system is obtained. The first obtained metrology data is not one of the metrology data in the set of metrology data earlier obtained. The first metrology data is transformed into a second metrology data using the one or more of the determined essential variables.

Abstract: The optimization of an optical metrology model for use in measuring a wafer structure is evaluated. An optical metrology model having metrology model variables, which includes profile model parameters of a profile model, is developed. One or more goals for metrology model optimization are selected. One or more profile model parameters to be used in evaluating the one or more selected goals are selected. One or more metrology model variables to be set to fixed values are selected. One or more selected metrology model variables are set to fixed values. One or more termination criteria for the one or more selected goals are set. The optical metrology model is optimized using the fixed values for the one or more selected metrology model variables. Measurements for the one or more selected profile model parameters are obtained using the optimized optical metrology model. A determination is then made as to whether the one or more termination criteria are met by the obtained measurements.

Abstract: An exemplary method and system for generating integrated circuit (IC) simulation information regarding the effect of design and fabrication process decisions includes creating and using a data store of profile-based information comprising metrology signal, structure profile data, process control parameters, and IC simulation attributes. An exemplary method and system for generating a simulation data store using signals off test gratings that model the effect of an IC design and/or fabrication process includes creating and using a simulation data store generated using test gratings that model the geometries of the IC interconnects. The interconnect simulation data store may be used in-line for monitoring electrical and thermal properties of an IC device during fabrication. Other embodiments include utilizing a metrology simulator and various combinations of a fabrication process simulator, a device simulator, and/or circuit simulator.

Abstract: Specific wavelengths to use in optical metrology of an integrated circuit can be selected using one or more selection criteria and termination criteria. Wavelengths are selected using the selection criteria, and the selection of wavelengths is iterated until the termination criteria are met.

Abstract: The optimization of an optical metrology model for use in measuring a wafer structure is evaluated. An optical metrology model having metrology model variables, which includes profile model parameters of a profile model, is developed. One or more goals for metrology model optimization are selected. One or more profile model parameters to be used in evaluating the one or more selected goals are selected. One or more metrology model variables to be set to fixed values are selected. One or more selected metrology model variables are set to fixed values. One or more termination criteria for the one or more selected goals are set. The optical metrology model is optimized using the fixed values for the one or more selected metrology model variables. Measurements for the one or more selected profile model parameters are obtained using the optimized optical metrology model. A determination is then made as to whether the one or more termination criteria are met by the obtained measurements.