摘要:
Provided is a method for determining profile parameters of a sample structure on a workpiece using an optical metrology system optimized to achieve one or more accuracy targets, the optical metrology system including an optical metrology tool, an optical metrology tool model, a profile model of the sample structure, and a parameter extraction algorithm, the method comprising: setting one or more accuracy targets for profile parameter determination for the sample structure; selecting a number of rays and beam propagation parameters to be used to model the optical metrology tool, measuring a diffraction signal off the sample structure using the optical metrology tool, generating a metrology output signal, determining an adjusted metrology output signal using the metrology output signal and calibration data, concurrently optimizing the optical metrology tool model and the profile model using the adjusted metrology output signal and the parameter extraction algorithm.
摘要:
Provided is a method for determining profile parameters of a sample structure on a workpiece using an optical metrology system optimized to achieve one or more accuracy targets, the optical metrology system including an optical metrology tool, an optical metrology tool model, a profile model of the sample structure, and a parameter extraction algorithm, the method comprising: setting one or more accuracy targets for profile parameter determination for the sample structure; selecting a number of rays and beam propagation parameters to be used to model the optical metrology tool, measuring a diffraction signal off the sample structure using the optical metrology tool, generating a metrology output signal, determining an adjusted metrology output signal using the metrology output signal and calibration data, concurrently optimizing the optical metrology tool model and the profile model using the adjusted metrology output signal and the parameter extraction algorithm.
摘要:
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.
摘要:
An optical metrology model for the structure is obtained. The optical metrology model comprising one or more profile parameters, one or more process parameters, and a dispersion. A dispersion function that relates the dispersion to at least one of the one or more process parameters is obtained. A simulated diffraction signal is generated using the optical metrology model and a value for the at least one of the process parameters and a value for the dispersion. The value for the dispersion is calculated using the value for the at least one of the process parameter and the dispersion function. A measured diffraction signal of the structure is obtained using an optical metrology tool. The measured diffraction signal is compared to the simulated diffraction signal to determine one or more profile parameters of the structure. The fabrication tool is controlled based on the determined one or more profile parameters of the structure.
摘要:
Provided is a method of controlling a fabrication cluster using a machine learning system, the machine learning system trained developed using an optical metrology model, the optical metrology model comprising a profile model, an approximation diffraction model, and a fine diffraction model. A simulated approximation diffraction signal is generated based on an approximation diffraction model of the structure. A set of difference diffraction signal is obtained by subtracting the simulated approximation diffraction signal from each of simulated fine diffraction signals and paired with the corresponding profile parameters. A first machine learning system is trained using the pairs of difference diffraction signal and corresponding profile parameters. A library of simulated fine diffraction signals and profile parameters is generated using the trained first machine learning system and using ranges and corresponding resolutions of the profile parameters. The library is used to train a second machine learning system. A measured diffraction signal is input into the trained second machine learning system to determine at least one profile parameter. The at least one profile parameter is used to adjust at least one process parameter or equipment setting of the fabrication cluster.
摘要:
A patterned structure in a wafer is created using one or more fabrication treatment processes. The patterned structure has a treated and an untreated portion. One or more diffraction sensitivity enhancement techniques are applied to the structure, the one or more diffraction sensitivity enhancement techniques adjusting one or more properties of the patterned structure to enhance diffraction contrast between the treated portion and untreated portions. A first diffraction signal is measured off an unpatterned structure on the wafer using an optical metrology device. A second diffraction signal is measured off the patterned structure on the wafer using the optical metrology device. One or more diffraction sensitivity enhancement techniques are selected based on comparisons of the first and second diffraction signals.
摘要:
To train a machine learning system, a set of different values of one or more photoresist parameters, which characterize behavior of photoresist when the photoresist undergoes processing steps in a wafer application, is obtained. A set of diffraction signals is obtained using the set of different values of the one or more photoresist parameters. The machine learning system is trained using the set of measured diffraction signals as inputs to the machine learning system and the set of different values of the one or more photoresist parameters as expected outputs of the machine learning system.
摘要:
Provided is a method of designing an optical metrology system for measuring structures on a workpiece wherein the optical metrology system is configured to meet a plurality of design goals. The design of the optical metrology system is optimized by using collected design goal data in comparison to the set plurality of design goals. In one embodiment, the optical metrology system is used for stand alone metrology systems. In another embodiment, the optical metrology system is integrated with a fabrication cluster in semiconductor manufacturing. At least one parameter determined from a diffraction signal measured using the optical metrology system is transmitted to the fabrication cluster. The at least one parameter is used to modify at least one process variable or equipment setting of the fabrication cluster.
摘要:
An optical metrology model for the structure is obtained. The optical metrology model comprising one or more profile parameters, one or more process parameters, and a dispersion. A dispersion function that relates the dispersion to at least one of the one or more process parameters is obtained. A simulated diffraction signal is generated using the optical metrology model and a value for the at least one of the process parameters and a value for the dispersion. The value for the dispersion is calculated using the value for the at least one of the process parameter and the dispersion function. A measured diffraction signal of the structure is obtained using an optical metrology tool. The measured diffraction signal is compared to the simulated diffraction signal to determine one or more profile parameters of the structure. The fabrication tool is controlled based on the determined one or more profile parameters of the structure.
摘要:
Provided is a method of controlling a fabrication cluster using a machine learning system, the machine learning system trained developed using an optical metrology model. A simulated approximation diffraction signal is generated based on an approximation diffraction model of the structure. A set of difference diffraction signal is obtained by subtracting the simulated approximation diffraction signal from each of simulated fine diffraction signals and paired with the corresponding profile parameters. A first machine learning system is trained using the pairs of difference diffraction signal and corresponding profile parameters. A library of simulated fine diffraction signals and profile parameters is generated using the trained first machine learning system and using ranges and corresponding resolutions of the profile parameters. A measured diffraction signal is input into the trained second machine learning system to determine at least one profile parameter. The at least one profile parameter is used to adjust at least one process parameter or equipment setting of the fabrication cluster.