Abstract: Various methods and systems for creating or performing a dynamic sampling scheme for a process during which measurements are performed on wafers are provided. One method for creating a dynamic sampling scheme for a process during which measurements are performed on wafers includes performing the measurements on all of the wafers in at least one lot at all measurement spots on the wafers. The method also includes determining an optimal sampling scheme, an enhanced sampling scheme, a reduced sampling scheme, and thresholds for the dynamic sampling scheme for the process based on results of the measurements. The thresholds correspond to values of the measurements at which the optimal sampling scheme, the enhanced sampling scheme, and the reduced sampling scheme are to be used for the process.

Abstract: A polarizing device may be used with sample inspection system having one or more collection systems that receive scattered radiation from a region on a sample surface and direct it to a detector. The polarizing device disposed between the collection system(s) and the detector. The polarizing device may include a plurality of polarizing sections. The sections may be characterized by different polarization characteristics. The polarizing device is configured to transmit scattered radiation from defects to the detector and to block noise from background sources that do not share characteristics with scattered radiation from the defects from reaching the detector while, maximizing a capture rate for the defects the detector at a less than optimal signal-to-noise ratio.

Abstract: Various methods and systems for determining a defect criticality index (DCI) for defects on wafers are provided. One computer-implemented method includes determining critical area information for a portion of a design for a wafer surrounding a defect detected on the wafer by an inspection system based on a location of the defect reported by the inspection system and a size of the defect reported by the inspection system. The method also includes determining a DCI for the defect based on the critical area information, a location of the defect with respect to the critical area information, and the reported size of the defect.

Abstract: Various systems and methods for creating persistent data for a wafer and using persistent data for inspection-related functions are provided. One system includes a set of processor nodes coupled to a detector of an inspection system. Each of the processor nodes is configured to receive a portion of image data generated by the detector during scanning of a wafer. The system also includes an array of storage media separately coupled to each of the processor nodes. The processor nodes are configured to send all of the image data or a selected portion of the image data received by the processor nodes to the arrays of storage media such that all of the image data or the selected portion of the image data generated by the detector during the scanning of the wafer is stored in the arrays of the storage media.

Abstract: Methods and systems for generating an inspection process for a wafer are provided. One computer-implemented method includes separately determining a value of a local attribute for different locations within a design for a wafer based on a defect that can cause at least one type of fault mechanism at the different locations. The method also includes determining a sensitivity with which defects will be reported for different locations on the wafer corresponding to the different locations within the design based on the value of the local attribute. In addition, the method includes generating an inspection process for the wafer based on the determined sensitivity. Groups may be generated based on the value of the local attribute thereby assigning pixels that will have at least similar noise statistics to the same group, which can be important for defect detection algorithms. Better segmentation may lead to better noise statistics estimation.

Abstract: Computer-implemented methods, computer-readable media, and systems for identifying one or more optical modes of an inspection system as candidates for use in inspection of a layer of a wafer are provided. One method includes determining one or more characteristics of images of the layer of the wafer acquired using the inspection system and different optical modes available on the inspection system. The method also includes identifying a first portion of the different optical modes as not candidates for use in the inspection of the layer of the wafer based on the one or more characteristics of the images. In addition, the method includes generating output by eliminating the first portion of the different optical modes from the different optical modes at which the images were acquired such that the output includes a second portion of the different optical modes indicated as the candidates for use in the inspection.

Abstract: Computer-implemented methods, carrier media, and systems for selecting polarization settings for an inspection system for inspection of a layer of a wafer are provided. One method includes detecting a population of defects on the layer of the wafer using results of each of two or more scans of the wafer performed with different combinations of polarization settings of the inspection system for illumination and collection of light scattered from the wafer. The method also includes identifying a subpopulation of the defects for each of the different combinations, each of which includes the defects that are common to at least two of the different combinations, and determining a characteristic of a measure of signal-to-noise for each of the subpopulations. The method further includes selecting the polarization settings for the illumination and the collection to be used for the inspection corresponding to the subpopulation having the best value for the characteristic.

Abstract: Methods and systems for detecting defects on a reticle are provided. One method includes printing a single die reticle in first areas of a wafer using different values of a parameter of a lithography process and at least one second area using a nominal value of the parameter. The method also includes acquiring first images of the first areas and second image(s) of the at least one second area. In addition, the method includes separately comparing the first images acquired for different first areas to at least one of the second image(s). The method further includes detecting defects on the reticle based on first portions of the first images in which variations in the first images compared to the at least one second image are greater than second portions of the first images and the first portions that are common to two or more of the first images.

Abstract: Methods and systems for generating information to be used for selecting values for parameter(s) of a detection algorithm are provided. One method includes without user intervention performing a scan of an area of a wafer using an inspection system and default values for parameter(s) of a detection algorithm to detect defects on the wafer. The method also includes selecting a portion of the defects from results of the scan based on a predetermined maximum number of total defects to be used for selecting values for the parameter(s) of the detection algorithm. The method further includes storing information, which includes values for the parameter(s) of the detection algorithm determined for the defects in the portion. The information can be used to select the values for the parameter(s) of the detection algorithm to be used for the inspection recipe without performing an additional scan of the wafer subsequent to the scan.

Abstract: Various computer-implemented methods for determining if actual defects are potentially systematic defects or potentially random defects are provided. One computer-implemented method for determining if actual defects are potentially systematic defects or potentially random defects includes comparing a number of actual defects in a group to a number of randomly generated defects in a group. The actual defects are detected on a wafer. A portion of a design on the wafer proximate a location of each of the actual defects in the group and each of the randomly generated defects in the group is substantially the same. The method also includes determining if the actual defects in the group are potentially systematic defects or potentially random defects based on results of the comparing step.

Abstract: Computer-implemented methods, systems, and computer-readable media for determining a model for predicting printability of reticle features on a wafer are provided. One method includes generating simulated images of the reticle features printed on the wafer using different generated models for a set of different values of exposure conditions. The method also includes determining one or more characteristics of the reticle features of the simulated images. In addition, the method includes comparing the one or more characteristics of the reticle features of the simulated images to one or more characteristics of the reticle features printed on the wafer using a lithography process. The method further includes selecting one of the different generated models as the model to be used for predicting the printability of the reticle features based on results of the comparing step.

Abstract: Systems and methods for blocking specular reflection and suppressing modulation from periodic features on a specimen are provided. One inspection system configured to block specular reflection and suppress modulation in an image of a specimen includes an illumination subsystem configured to illuminate the specimen with a predetermined pattern of spatially incoherent light. The system also includes an optical element configured to block light reflected from periodic features formed on the specimen and at least some light diffracted from the periodic features. The system further includes a detector configured to detect light that passes through the optical element and to generate an image of the specimen in response to the detected light. The optical element blocks specular reflection and at least partially suppresses modulation in the image due to the periodic features. The system also includes a processor configured to detect defects on the specimen using the image.

Abstract: Systems and methods for determining two or more characteristics of a wafer are provided. The two or more characteristics include a characteristic of the wafer that is spatially localized in at least one dimension and a characteristic of the wafer that is not spatially localized in two dimensions.

Abstract: Various methods, designs, defect review tools, and systems for determining locations on a wafer to be reviewed during defect review are provided. One computer-implemented method includes acquiring coordinates of defects detected by two or more inspection systems. The defects do not include defects detected on the wafer. The method also includes determining coordinates of the locations on the wafer to be reviewed during the defect review by translating the coordinates of the defects into the coordinates on the wafer such that results of the defect review performed at the locations can be used to determine if the defects cause systematic defects on the wafer.

Abstract: Systems and methods for creating inspection recipes are provided. One computer-implemented method for creating an inspection recipe includes acquiring a first design and one or more characteristics of output of an inspection system for a wafer on which the first design is printed using a manufacturing process. The method also includes creating an inspection recipe for a second design using the first design and the one or more characteristics of the output acquired for the wafer on which the first design is printed. The first and second designs are different. The inspection recipe will be used for inspecting wafers after the second design is printed on the wafers using the manufacturing process.

Abstract: Methods for generating a standard reference die for use in a die to standard reference die inspection and methods for inspecting a wafer are provided. One computer-implemented method for generating a standard reference die for use in a die to standard reference die inspection includes acquiring output of an inspection system for a centrally located die on a wafer and one or more dies located on the wafer. The method also includes combining the output for the centrally located die and the one or more dies based on within die positions of the output. In addition, the method includes generating the standard reference die based on results of the combining step.

Abstract: Various computer-implemented methods, carrier media, and systems for stabilizing output acquired by an inspection system are provided. One computer-implemented method includes determining a characteristic of output acquired for a wafer by an inspection system using an inspection recipe. The method also includes comparing the characteristic to a reference characteristic. In addition, if the characteristic is above the reference characteristic, the method includes altering the output acquired for the wafer such that the characteristic of the altered output substantially matches the reference characteristic thereby stabilizing the output acquired for the wafer to the reference characteristic.

Abstract: Systems and methods for detecting defects on a wafer and generating inspection results for the wafer are provided. One method includes detecting defects on a wafer by comparing output generated by scanning of the wafer performed by an inspection system to one or more defect detection thresholds. The method also includes sampling outliers in the output by selecting the output having the highest values from bins defined based on one or more predetermined criteria. In addition, the method includes selecting a portion of the sampled outliers based on wafer-level analysis of the sampled outliers. The method further includes generating inspection results for the wafer by combining information about the selected portion of the sampled outliers with information about the defects detected using the one or more defect detection thresholds.

Abstract: Methods for detecting and classifying defects on a reticle are provided. One method includes acquiring images of the reticle at first and second conditions during inspection of the reticle. The first condition is different than the second condition. The method also includes detecting the defects on the reticle using one or more of the images acquired at the first condition. In addition, the method includes classifying an importance of the defects detected on the reticle using one or more of the images acquired at the second condition. The detecting and classifying steps are performed substantially simultaneously during the inspection.

Abstract: A modulated reflectance measurement system includes lasers for generating an intensity modulated pump beam and a UV probe beam. The pump and probe beams are focused on a measurement site within a sample. The pump beam periodically excites the measurement site and the modulation is imparted to the probe beam. For one embodiment, the wavelength of the probe beam is selected to correspond to a local maxima of the temperature reflectance coefficient of the sample. For a second embodiment, the probe laser is tuned to either minimize the thermal wave contribution to the probe beam modulation or to equalize the thermal and plasma wave contributions to the probe beam modulation.