Patent application number | Description | Published |
20080231863 | Automated process control using optical metrology with a photonic nanojet - A fabrication cluster can be controlled using optical metrology. A fabrication process is performed on a wafer using a fabrication cluster. A photonic nanojet, an optical intensity pattern induced at a shadow-side surface of a dielectric microsphere, is generated. An inspection area on the wafer is scanned with the photonic nanojet. A measurement is obtained of the retroreflected light from the dielectric microsphere as the photonic nanojet scans the inspection area. The existence of a structure in the inspection area is determined with the obtained measurement of the retroreflected light. One or more process parameters of the fabrication cluster is adjusted based on the determination of the existence of the structure in the inspection area. | 09-25-2008 |
20080252908 | CONTROLLING A FABRICATION TOOL USING SUPPORT VECTOR MACHINE - A fabrication tool can be controlled using a support vector machine. A profile model of the structure is obtained. The profile model is defined by profile parameters that characterize the geometric shape of the structure. A set of values for the profile parameters is obtained. A set of simulated diffraction signals is generated using the set of values for the profile parameters, each simulated diffraction signal characterizing the behavior of light diffracted from the structure. The support vector machine is trained using the set of simulated diffraction signals as inputs to the support vector machine and the set of values for the profile parameters as expected outputs of the support vector machine. After the support vector machine has been trained, a fabrication process is performed using the fabrication tool to fabricate the structure on the wafer. A measured diffraction signal off the structure is obtained. The measured diffraction signal is inputted into the trained support vector machine. Values of profile parameters of the structure are obtained as an output from the trained support vector machine. One or more process parameters or equipment settings of the fabrication tool are adjusted based on the obtained values of the profile parameters. | 10-16-2008 |
20080255786 | Optical metrology using support vector machine with profile parameter inputs - A structure formed on a semiconductor wafer can be examined using a support vector machine. A profile model of the structure is obtained. The profile model is defined by profile parameters that characterize the geometric shape of the structure. A training set of values for the profile parameters is obtained. A training set of simulated diffraction signals is generated using the training set of values for the profile parameters, each simulated diffraction signal characterizing the behavior of light diffracted from the structure. The support vector machine is trained using the training set of values for the profile parameters as inputs to the support vector machine and the training set of simulated diffraction signals as expected outputs of the support vector machine. A measured diffraction signal off the structure is obtained. A simulated diffraction signal is generated using a set of values for the profile parameters as inputs to the trained support vector machine. The measured diffraction signal is compared to the simulated diffraction signal. When the measured diffraction signal and simulated diffraction signal match within one or more matching criteria, values of profile parameters of the structure are determined to be the set of values for the profile parameters used to generate the simulated diffraction signal. | 10-16-2008 |
20080255801 | Optical metrology using a support vector machine with simulated diffraction signal inputs - A structure formed on a semiconductor wafer can be examined using a support vector machine. A profile model of the structure is obtained. The profile model is defined by profile parameters that characterize the geometric shape of the structure. A set of values for the profile parameters is obtained. A set of simulated diffraction signals is generated using the set of values for the profile parameters, each simulated diffraction signal characterizing the behavior of light diffracted from the structure. The support vector machine is trained using the set of simulated diffraction signals as inputs to the support vector machine and the set of values for the profile parameters as expected outputs of the support vector machine. A measured diffraction signal off the structure is obtained. The measured diffraction signal is inputted into the trained support vector machine. Values of profile parameters of the structure are obtained as an output from the trained support vector machine. | 10-16-2008 |
20080291429 | AUTOMATED PROCESS CONTROL USING PARAMETERS DETERMINED FROM A PHOTOMASK COVERED BY A PELLICLE - Provided is a method of controlling a photolithography cluster or a subsequent fabrication cluster using optical metrology to determine profile parameters of a photomask structure covered with a pellicle. An optical metrology model of the pellicle is developed and integrated with the optical metrology model of the photomask structure. The optical metrology model of the photomask taking into account the optical effects on the illumination and detection beams transmitted through the pellicle and diffracted by the photomask structure. One or more profile parameters of the photomask structure is determined and used to adjust one or more process parameters or equipment settings of a photolithography cluster using the photomask or a subsequent fabrication cluster. | 11-27-2008 |
20080291467 | DETERMINING ONE OR MORE PROFILE PARAMETERS OF A PHOTOMASK COVERED BY A PELLICLE - Provided is a method of determining one or more profile parameters of a photomask covered with a pellicle, the method comprising developing an optical metrology model of a pellicle covering a photomask, developing an optical metrology model of the photomask, the photomask separated from the pellicle by a medium and having a structure, the structure having profile parameters, the optical metrology model of the photomask taking into account the optical effects on the illumination beam transmitted through the pellicle and diffracted by the photomask structure. The optical metrology model of the pellicle and the optical metrology model of the photomask structure are integrated and optimized. At least one profile parameters of the photomask structure is determined using the optimized integrated optical metrology model. | 11-27-2008 |
20090063075 | DETERMINING PROFILE PARAMETERS OF A STRUCTURE USING APPROXIMATION AND FINE DIFFRACTION MODELS IN OPTICAL METROLOGY - Provided is a method for determining one or more profile parameters of a structure 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 signals is obtained by subtracting the simulated approximation diffraction signal from each of simulated fine diffraction signals and paired with the corresponding profile parameters and used to generate a library of difference diffraction signals. A measured diffraction signal adjusted by the simulated approximation diffraction signal is matched against the library to determine at least one profile parameter of the structure. | 03-05-2009 |
20090063076 | Determining profile parameters of a structure using approximation and fine diffraction models in optical metrology - Provided is a method for determining one or more profile parameters of a structure 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 signals is obtained by subtracting the simulated approximation diffraction signal from each of simulated fine diffraction signals and paired with the corresponding profile parameters. A machine learning system is trained using the pairs of difference diffraction signal and corresponding profile parameters. A measured diffraction signal adjusted by the simulated approximation diffraction signal is input into the trained machine learning system and generates the corresponding profile parameters. | 03-05-2009 |
20090063077 | AUTOMATED PROCESS CONTROL USING PARAMETERS DETERMINED WITH APPROXIMATION AND FINE DIFFRACTION MODELS - 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. | 03-05-2009 |
20090076782 | GENERATING SIMULATED DIFFRACTION SIGNAL USING A DISPERSION FUNCTION RELATING PROCESS PARAMETER TO DISPERSION - A first wafer is fabricated using a first value for a process parameter specifying a process condition in fabricating the structure. A first value of a dispersion is measured from the first wafer. A second wafer is fabricated using a second value for the process parameter. A second value of the dispersion is measured from the second wafer. A third wafer is fabricated using a third value for the process parameter. The first, second, and third values for the process parameter are different from each other. A third value of the dispersion is measured from the third wafer. A dispersion function is defined to relate the process parameter to the dispersion using the first, second, and third values for the process parameter and the measured first, second, and third values of the dispersion. The simulated diffraction signal is generated using the defined dispersion function. The simulated diffraction signal is stored. | 03-19-2009 |
20090082993 | AUTOMATED PROCESS CONTROL OF A FABRICATION TOOL USING A DISPERSION FUNCTION RELATING PROCESS PARAMETER TO DISPERSION - 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. | 03-26-2009 |
20090083013 | DETERMINING PROFILE PARAMETERS OF A STRUCTURE FORMED ON A SEMICONDUCTOR WAFER USING A DISPERSION FUNCTION RELATING PROCESS PARAMETER TO DISPERSION - An optical metrology model is created for a structure formed on a semiconductor wafer. The optical metrology model comprises one or more profile parameters, one or more process parameters, and dispersion. A dispersion function is obtained that relates the dispersion to at least one of the one or more process parameters. 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. The measured diffraction signal is compared to the simulated diffraction signal. One or more profile parameters of the structure and one or more process parameters are determined based on the comparison of the measured diffraction signal to the simulated diffraction signal. | 03-26-2009 |
20090187383 | Noise-Reduction Metrology Models - The invention can provide apparatus and methods for processing wafers using Noise-Reduction (N-R) metrology models that can be used in Double-Patterning (D-P) processing sequences, Double-Exposure (D-E) processing sequences, or other processing sequences. | 07-23-2009 |
20100007875 | Field Replaceable Units (FRUs) Optimized for Integrated Metrology (IM) - An Integrated Metrology Sensor (IMS) including a plurality of Field Replaceable Units (FRUs) for measuring a target on a wafer. The FRU configurations can be optimized to include the appropriate elements, so that each FRU can be pre-aligned and calibrated in the factory to minimize the time need to swap the FRU in the field due to failure or scheduled maintenance. The FRU configuration of the IMS is optimized to shorten the time to repair a failure or perform scheduled maintenance and increase the system reliability. | 01-14-2010 |
20100007885 | Pre-Aligned Metrology System and Modules - A Pre-Aligned Metrology System comprising a number of Pre-Aligned Metrology Assemblies and Pre-Aligned Metrology Modules for measuring a target on a wafer. The Pre-Aligned Metrology Assemblies and Pre-Aligned Metrology Modules can reduce the maintenance down time and decrease the cost of ownership (COO). | 01-14-2010 |
20100010765 | System and Method for Azimuth Angle Calibration - An improved procedure for calibrating the azimuth angle in a metrology module for use in a metrology system that is used for measuring a target on a wafer, and the metrology modules can include oblique Spectroscopic Ellipsometry (SE) and unpolarized or polarized spectroscopic reflectometer devices. | 01-14-2010 |
20100042388 | COMPUTATION EFFICIENCY BY DIFFRACTION ORDER TRUNCATION - A method for improving computation efficiency for diffraction signals in optical metrology is described. The method includes simulating a set of diffraction orders for a three-dimensional structure. The diffraction orders within the set of diffraction orders are then prioritized. The set of diffraction orders is truncated to provide a truncated set of diffraction orders based on the prioritizing. Finally, a simulated spectrum is provided based on the truncated set of diffraction orders. | 02-18-2010 |
20100245807 | OPTIMIZING SENSITIVITY OF OPTICAL METROLOGY MEASUREMENTS - Provided is a method of optimizing sensitivity of measurements of an optical metrology tool using two or more illumination beams directed to a structure on a workpiece comprising selecting target structures for measurement, obtaining diffraction signals off the selected structures as a function of angle of incidence for each illumination beam, determining a selected angle of incidence for each of the two or more illumination beams, setting sensitivity objectives for optical metrology measurements, developing a design for the optical metrology tool to achieve the corresponding selected angle of incidence of the two or more illumination beams, obtaining sensitivity data using the optical metrology tool, and if the sensitivity objectives are not met, adjusting the selection of target structures, the selected angle of incidence of the two or more illumination beams, the sensitivity objectives, and/or the design of the optical metrology tool, and iterating the developing of the design, obtaining sensitivity data, and comparing sensitivity data to sensitivity objectives until the sensitivity objectives are met. | 09-30-2010 |
20110245955 | AUTOMATED PROCESS CONTROL USING AN ADJUSTED METROLOGY OUTPUT SIGNAL - Provided is a method for controlling a fabrication cluster using an optical metrology system that includes an optical metrology tool, an optical metrology model, and a profile extraction algorithm. The method comprises: selecting a number of rays for the illumination beam, selecting beam propagation parameters, using a processor, determining beam propagation parameters from the light source of the to the sample structure, determining the beam propagation parameters from the sample structure to the detector, calculating intensity and polarization of each ray on the detector, generating a total intensity and polarization of the diffraction beam, calculating a metrology output signal from the total intensity and polarization, extracting the one or more profile parameters using the metrology output signal, transmitting at least one profile parameter to a fabrication cluster, and adjusting at least one process parameter or equipment setting of the fabrication cluster. | 10-06-2011 |
20110246141 | METHOD OF OPTICAL METROLOGY OPTIMIZATION USING RAY TRACING - Provided is a method for determining a profile of a sample structure on a workpiece using an optical metrology system that includes an optical metrology tool, an optical metrology model, and a profile extraction algorithm. The method comprises selecting a number of rays for the illumination beam, selecting beam propagation parameters, and using a processor, determining beam propagation parameters for each ray of the selected number of rays, determining the beam propagation parameters for each ray, calculating intensity and polarization of each ray, calculating total intensity and polarization of the diffraction beam, calculating a metrology output signal, extracting one or more profile parameters using the metrology output signal, calibration data, and a profile extraction algorithm. | 10-06-2011 |
20110246142 | OPTIMIZATION OF RAY TRACING AND BEAM PROPAGATION PARAMETERS - 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. | 10-06-2011 |
20110246400 | SYSTEM FOR OPTICAL METROLOGY OPTIMIZATION USING RAY TRACING - Provided is a system 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 comprises an optical metrology tool configured to measure a diffraction signal off a sample structure, an optical metrology tool model configured to model the optical metrology tool using a selected number of rays and selected beam propagation parameters for the illumination beam and the diffraction beam; a signal adjuster configured to adjust the measured diffraction signal off the sample structure using the optical metrology tool model and calibration parameters, the signal adjuster generating an adjusted metrology output signal; and a profile extractor configured to determine one or more profile parameters of the sample structure using the adjusted metrology output signal, a profile model of the sample structure, and one or more extraction modules. | 10-06-2011 |
20130084655 | OVERLAY MEASUREMENT FOR A DOUBLE PATTERNING - A multi-patterning method of manufacturing a patterned wafer provides test structures designed to enhance overlay error measurement sensitivity for monitoring and process control. One or more patterns are overlaid on a first pattern, each of a given pitch, with the elements interleaved. Test structure is formed with elements of the overlaid patterns spaced away from respective mid-positions more closely toward elements of the first pattern. In some embodiments, test structure elements of the second pattern are overlaid midway between mid-positions of elements of the first pattern and measured by scatterometry. In other embodiments, test structure elements of the second pattern are overlaid at a slightly different pitch than the elements of the first pattern and measured by reflectivity. Measurements are compared with library measurements to identify the error, which may be fed back to control the patterning process. The multi-patterning may be formed by LELE, LLE, LFLE, or other methods. | 04-04-2013 |
20130148130 | PROCESS CONTROL USING RAY TRACING-BASED LIBRARIES AND MACHINE LEARNING SYSTEMS - Provided is a method for controlling a fabrication cluster comprising an optical metrology tool and an optical metrology model including a profile model of a sample structure, the optical metrology tool having an illumination beam, the illumination beam having a range of angles of incidence and azimuth angles. A library comprising Jones and/or Mueller matrices and/or components (JMMOC) and corresponding profile parameters is generated using ray tracing and a selected range of beam propagation parameters and can be used to train a machine learning system (MLS). A regenerated simulated diffraction signal is obtained with a regenerated JMMOC using the library or MLS, integrated for all the rays of the optical metrology model. One or more profile parameters are determined from the best match regenerated simulated diffraction signal. At least one process parameter of the fabrication cluster is adjusted based on the determined one or more profile parameters. | 06-13-2013 |
20130151211 | METHOD OF ENHANCING AN OPTICAL METROLOGY SYSTEM USING RAY TRACING AND FLEXIBLE RAY LIBRARIES - Provided is a method of enhancing an optical metrology system comprising a metrology tool and an optical metrology model. The optical metrology model includes a model of the metrology tool and a profile model of the sample structure. A first library comprising Jones and/or Mueller matrices or components (JMMOC) is generated using ray tracing based on a representative ray. A difference library is generated comprising difference JMMOC for each ray of the set of rays, calculated using the difference from the representative JMMOC. During profile extraction, the JMMOC of the representative ray and each ray of the set of rays are regenerated using the first and difference libraries and a best match simulated diffraction signal is obtained using the regenerated JMMOC of the representative ray, regenerated JMMOC of the rays, and the optical metrology model to determine profile parameters of the sample structure. | 06-13-2013 |
20130151440 | METHOD OF REGENERATING DIFFRACTION SIGNALS FOR OPTICAL METROLOGY SYSTEMS - Provided is a method for enhancing accuracy of an optical metrology system that includes a metrology tool, an optical metrology model, and a profile extraction algorithm. The optical metrology model includes a model of the metrology tool and a profile model of the sample structure, the profile model having profile parameters. A library comprising Jones and/or Mueller matrices and/or components (JMMOC) and corresponding profile parameters is generated using ray tracing and a selected range of beam propagation parameters. An original simulated diffraction signal is calculated using the optical metrology model. A regenerated simulated diffraction signal is obtained using the regenerated JMMOC, integrated for all the rays of the optical metrology model. If an error and precision criteria for the regenerated simulated diffraction signal compared to the original simulated diffraction signal are met, one or more profile parameters are determined from the best match regenerated simulated diffraction signal. | 06-13-2013 |
20140024143 | SYSTEM FOR IN-SITU FILM STACK MEASUREMENT DURING ETCHING AND ETCH CONTROL METHOD - Disclosed is an in-situ optical monitor (ISOM) system and associated method for controlling plasma etching processes during the forming of stepped structures in semiconductor manufacturing. The in-situ optical monitor (ISOM) can be optionally configured for coupling to a surface-wave plasma source (SWP), for example a radial line slotted antenna (RLSA) plasma source. A method is described to correlate the lateral recess of the steps and the etched thickness of a photoresist layer for use with the in-situ optical monitor (ISOM) during control of plasma etching processes in the forming of stepped structures. | 01-23-2014 |