Patent application number | Description | Published |
20120226644 | Accurate and Fast Neural network Training for Library-Based Critical Dimension (CD) Metrology - Approaches for accurate neural network training for library-based critical dimension (CD) metrology are described. Approaches for fast neural network training for library-based CD metrology are also described. | 09-06-2012 |
20130158957 | LIBRARY GENERATION WITH DERIVATIVES IN OPTICAL METROLOGY - Methods of library generation with derivatives for optical metrology are described. For example, a method of generating a library for optical metrology includes determining a function of a parameter data set for one or more repeating structures on a semiconductor substrate or wafer. The method also includes determining a first derivative of the function of the parameter data set. The method also includes providing a spectral library based on both the function and the first derivative of the function. | 06-20-2013 |
20130262044 | MODEL OPTIMIZATION APPROACH BASED ON SPECTRAL SENSITIVITY - Model optimization approaches based on spectral sensitivity is described. For example, a method includes determining a first model of a structure. The first model is based on a first set of parameters. A set of spectral sensitivity variations data is determined for the structure. Spectral sensitivity is determined by derivatives of the spectra with respect to the first set of parameters. The first model of the structure is modified to provide a second model of the structure based on the set of spectral sensitivity variations data. The second model of the structure is based on a second set of parameters different from the first set of parameters. A simulated spectrum derived from the second model of the structure is then provided. | 10-03-2013 |
20140032463 | ACCURATE AND FAST NEURAL NETWORK TRAINING FOR LIBRARY-BASED CRITICAL DIMENSION (CD) METROLOGY - Approaches for accurate neural network training for library-based critical dimension (CD) metrology are described. Approaches for fast neural network training for library-based CD metrology are also described. | 01-30-2014 |
20140358485 | AUTOMATIC WAVELENGTH OR ANGLE PRUNING FOR OPTICAL METROLOGY - Automatic wavelength or angle pruning for optical metrology is described. An embodiment of a method for automatic wavelength or angle pruning for optical metrology includes determining a model of a structure including a plurality of parameters; designing and computing a dataset of wavelength-dependent or angle-dependent data for the model; storing the dataset in a computer memory; performing with a processor an analysis of the dataset for the model including applying an outlier detection technology on the dataset, and identifying any data outliers, each data outlier being a wavelength or angle; and, if any data outliers are identified in the analysis of the dataset of the model, removing the wavelengths or angles corresponding to the data outliers from the dataset to generate a modified dataset, and storing the modified dataset in the computer memory. | 12-04-2014 |
20140358488 | DYNAMIC REMOVAL OF CORRELATION OF HIGHLY CORRELATED PARAMETERS FOR OPTICAL METROLOGY - Dynamic removal of correlation of highly-correlated parameters for optical metrology is described. An embodiment of a method includes determining a model of a structure, the model including a set of parameters; performing optical metrology measurement of the structure, including collecting spectra data on a hardware element; during the measurement of the structure, dynamically removing correlation of two or more parameters of the set of parameters, an iteration of the dynamic removal of correlation including: generating a Jacobian matrix of the set of parameters, applying a singular value decomposition of the Jacobian matrix, selecting a subset of the set of parameters, and computing a direction of the parameter search based on the subset of parameters. If the model does not converge, performing one or more additional iterations of the dynamic removal of correlation until the model converges; and if the model does converge, reporting the results of the measurement. | 12-04-2014 |
20150142395 | AUTOMATIC SELECTION OF SAMPLE VALUES FOR OPTICAL METROLOGY - Embodiments include automatic selection of sample values for optical metrology. An embodiment of a method includes providing a library parameter space for modeling of a diffracting structure using an optical metrology system; automatically determining by a processing unit a reduced sampling set from the library parameter space, wherein the reduced space is based on one or both of the following recommending a sampling shape based on an expected sample space usage, or recommending a sampling filter based on correlation between two or more parameters of the library parameter space; and generating a library for the optical metrology system using the reduced sampling set. | 05-21-2015 |
20150199463 | Semiconductor Device Models Including Re-Usable Sub-Structures - Methods and tools for generating measurement models of complex device structures based on re-useable, parametric models are presented. Metrology systems employing these models are configured to measure structural and material characteristics associated with different semiconductor fabrication processes. The re-useable, parametric sub-structure model is fully defined by a set of independent parameters entered by a user of the model building tool. All other variables associated with the model shape and internal constraints among constituent geometric elements are pre-defined within the model. In some embodiments, one or more re-useable, parametric models are integrated into a measurement model of a complex semiconductor device. In another aspect, a model building tool generates a re-useable, parametric sub-structure model based on input from a user. The resulting models can be exported to a file that can be used by others and may include security features to control the sharing of sensitive intellectual property with particular users. | 07-16-2015 |