Abstract: An acousto-optic modulator (AOM) laser frequency shifter system includes a laser configured to generate an incident beam, a first optical splitter optically coupled to the laser and configured to split the incident beam into at least one portion of the incident beam, at least one phase-shift channel optically coupled to the first optical splitter and configured to generate at least one frequency-shifted beam with an acousto-optic modulator (AOM) from the at least one portion of the incident beam received from the first optical splitter, and a second optical splitter configured to receive the at least one frequency-shifted beam from the at least one phase-shift channel and configured to direct the at least one frequency-shifted beam to an interferometer configured to acquire an interferogram of a sample with the at least one frequency-shifted beam.

Abstract: A metrology system may include a controller to receive a first metrology dataset associated with a first set of metrology target features on a sample including first features from a first exposure field on a first sample layer and second features from a second exposure field on a second sample layer, where the second exposure field partially overlaps the first exposure field. The controller may further receive a second metrology dataset associated with a second set of metrology target features including third features from a third exposure field on the second layer that overlaps the first exposure field and fourth features formed from a fourth exposure field on the first layer of the sample that overlaps the second exposure field. The controller may further determine fabrication errors based on the first and second metrology datasets and generate correctables to adjust a lithography tool based on the fabrication errors.

Abstract: A system for characterizing a specimen is disclosed. In one embodiment, the system includes a controller configured to: receive training images of one or more defects of the specimen; generate a machine learning classifier based on the training images; receive product images of one or more defects of a specimen; determine one or more defect type classifications of one or more defects with the machine learning classifier; filter the product images with one or more smoothing filters; perform binarization processes to generate binarized product images; perform morphological image processing operations on the binarized product images; determine one or more algorithm-estimated defect sizes of the one or more defects based on the binarized product images; and determine one or more refined estimates of one or more defect sizes of the one or more defects based on the one or more algorithm-estimated defect sizes and the one or more defect type classifications.

Abstract: A focus-sensitive metrology target may be formed and read-out by a fabrication tool. A resulting overlay signal may be translated into a focus offset by comparison to a previously-determined calibration curve. One or more translated signals may be fed back to the fabrication tool for focus correction or used for prediction of on-device overlay (correction of overlay metrology results). In one embodiment, focus and overlay may be measured using a single target, where one portion of the target is formed on a first layer and includes a focus-sensitive design, and where another portion of the target is formed on a second layer and includes a relatively less focus-sensitive design. In some embodiments, a relative difference in focus response may be used to estimate an impact of focus error on device overlay and calculate non-zero offset contributions.

Abstract: Methods and systems for measuring structural and material characteristics of semiconductor structures based on wavelength resolved, soft x-ray reflectometry (WR-SXR) at multiple diffraction orders are presented. WR-SXR measurements are simultaneous, high throughput measurements over multiple diffraction orders with broad spectral width. The availability of wavelength resolved signal information at each of the multiple diffraction orders improves measurement accuracy and throughput. Each non-zero diffraction order includes multiple measurement points, each different measurement point associated with a different wavelength. In some embodiments, WR-SXR measurements are performed with x-ray radiation energy in a range of 10-5,000 electron volts at grazing angles of incidence in a range of 1-45 degrees. In some embodiments, the illumination beam is controlled to have relatively high divergence in one direction and relatively low divergence in a second direction, orthogonal to the first direction.

Abstract: A system includes a controller with processors configured to execute an auto-correlation module embodied in one or more sets of program instructions stored in memory. The auto-correlation module is configured to cause the processors to receive one or more patterned wafer geometry metrics, receive wafer characterization data from one or more characterization tools, determine a correlation between the one or more patterned wafer geometry metrics and the wafer characterization data, generate a ranking of the one or more patterned wafer geometry metrics based on the determined correlation, construct a composite metric model from a subset of the one or more patterned wafer geometry metrics based on the ranking of the one or more patterned wafer geometry metrics, generate one or more composite wafer metrics from the composite metric model, and generate a statistical process control output based on the one or more composite wafer metrics.

Abstract: A method and system for measuring misregistration between different layers of a semiconductor device, the method including providing a set of pupil inaccuracy scalable basis elements (PISBEs) relating to a plurality of patterned semiconductor device wafers (PSDWs), generating a single pupil image of a site on a PSDW, the PSDW being one of the plurality of PSDWs, by taking a single measurement of the site, the single pupil image including a plurality of site-specific pixels, calculating a set of site-specific pupil inaccuracy scalable basis element scaling factors (PISBESFs) for the single pupil image using the set of PISBEs and the plurality of site-specific pixels and calculating a site-specific misregistration value (SSMV) using the set of PISBEs and the set of site-specific PISBESFs.

Abstract: A rendered image is aligned with a scanning electron microscope (SEM) image to produce an aligned rendered image. A reference image is aligned with the SEM image to produce an aligned reference image. A threshold probability map also is generated. Dynamic compensation of the SEM image and aligned reference image can produce a corrected SEM image and corrected reference image. A thresholded defect map can be generated and the defects of the thresholded probability map and the signal-to-noise-ratio defects of the thresholded defect map are filtered using a broadband-plasma-based property to produce defect-of-interest clusters.

Abstract: A broadband radiation source is disclosed. The source may include a gas containment vessel configured to maintain a plasma and emit broadband radiation. The source may also include a recirculation gas loop fluidically coupled to the gas containment vessel. The recirculation gas loop may be configured to transport gas from one or more gas boosters configured to pressurize the low-pressure gas into a high-pressure gas and transport the high-pressure gas to the recirculation loop via an outlet. The system includes a pressurized gas reservoir fluidically coupled to the outlet of the one or more gas boosters and is configured to receive and store high pressure gas from the one or more gas boosters. The source includes a pressurized gas reservoir located between the one or more gas boosters and the gas containment vessel and is configured to receive and store high pressure gas from the one or more gas boosters.

Abstract: Heights on a surface of a photomask are measured using broadband light interferometry. The heights include heights of patterned areas of the photomask. A focal map is produced from the measured heights on the surface of the photomask. To produce the focal map, the measured heights of the patterned areas are adjusted based on fill factors for the patterned areas. The photomask is inspected for defects, using the focal map.

Abstract: An electron beam system and method are provided. The system includes a detector having a detector face configured to detect back-scattered electrons reflected off of a sample. The system further includes an annular cap disposed on the detector face, and a protective pellicle disposed on the annular cap, covering the detector face. The protective pellicle is transparent to back-scattered electrons and provides a physical barrier to particles directed at the detector face.

Abstract: A system for analyzing a sample includes an illumination source with a plurality of transmitting optical fibers optically coupled to the illumination source and a detector with a plurality of receiving optical fibers optically coupled to the detector. The system further includes a plurality of probes coupled to respective ones of the plurality of transmitting optical fibers and respective ones of the plurality of receiving optical fibers. The plurality of probes are configured to illuminate respective portions of a surface of the sample and configured to receive illumination reflected, refracted, or radiated from the respective portions of the surface of the sample. The system may further include one or more switches and/or splitters configured to optically couple respective ones of the plurality of transmitting optical fibers to the illumination source and/or configured to optically couple respective ones of the plurality of receiving optical fibers to the detector.

Abstract: A gripper assembly is disclosed. The gripper assembly includes a stage, a mounting platform, and a plurality of the flexible gripper elements. The flexible gripper element is configured to grip an object. The flexible gripper elements are supported by a first end piece, where the first end piece is attached to the mounting platform. The mounting platform is connected to the stage, where the stage is moveable. The flexible gripper element includes a hollow section that is selectively pressurizable. The hollow section includes one or more zones, where each zone includes chambers which are pressurizable by a fluid input. The selective pressurization of the hollow section allows the flexible gripper element to grip the object.

Abstract: An overlay metrology system may include an illumination sub-system to sequentially illuminate an overlay target with a first illumination lobe and a second illumination lobe opposite the first illumination lobe, where the overlay target includes grating-over-grating features formed from periodic structures on a first sample layer and a second sample layer. The system may further include an imaging sub-system to generate a first image and a second image of the overlay target. The first image includes an unresolved image of the grating-over-grating structures formed from a single non-zero diffraction order of the first illumination lobe. The second image includes an unresolved image of the one or more grating-over-grating structures formed from a single non-zero diffraction order of the second illumination lobe. The system may further include a controller to determine an overlay error between the first layer and the second layer based on the first image and the second image.

Abstract: Methods and systems for performing overlay and edge placement errors of device structures based on x-ray diffraction measurement data are presented. Overlay error between different layers of a metrology target is estimated based on the intensity variation within each x-ray diffraction order measured at multiple, different angles of incidence and azimuth angles. The estimation of overlay involves a parameterization of the intensity modulations of common orders such that a low frequency shape modulation is described by a set of basis functions and a high frequency overlay modulation is described by an affine-circular function including a parameter indicative of overlay. In addition to overlay, a shape parameter of the metrology target is estimated based on a fitting analysis of a measurement model to the intensities of the measured diffraction orders. In some examples, the estimation of overlay and the estimation of one or more shape parameter values are performed simultaneously.

Abstract: A method of manufacturing a semiconductor device includes defining a sampling plan in a process control system. Measurement values are obtained at the first number N of the sample points. The first number of measurement values are modelled using a wafer model to generate a first set of coefficients according to a reference model. A second number M of the first number N of sample points is randomly selected. The second number M of measurement values obtained at the second number M of sample points is modelled using the wafer model to generate a second set of coefficients according to a phase_1 model. One of the M sample points is randomly replaced by one of the N?M sample points to obtain a subsample. The measurement values of the subsample are modelled using the wafer model to generate a third set of coefficients according to a phase_2 model.

Abstract: A sample characterization system is disclosed. In embodiments, the sample characterization system includes a controller communicatively coupled to an inspection sub-system, the controller including one or more processors configured to execute a set of program instructions stored in memory, the set of program instructions configured to cause the one or more processors to: acquire one or more target image frames of a sample; generate a target tensor with the one or more acquired target image frames; perform a first set of one or more decomposition processes on the target tensor to generate one or more reference tensors including one or more reference image frames; identify one or more differences between the one or more target image frames and the one or more reference image frames; and determine one or more characteristics of the sample based on the one or more identified differences.

Abstract: A metrology system may receive a model for measuring one or more selected attributes of a target including features distributed in a selected pattern based on regression of spectroscopic scatterometry data from a scatterometry tool for a range of wavelengths. The metrology system may further generate a weighting function for the model to de-emphasize portions of the spectroscopic scatterometry data associated with wavelengths at which light captured by the scatterometry tool when measuring the target is predicted to include undesired diffraction orders. The metrology system may further direct the spectroscopic scatterometry tool to generate scatterometry data of one or more measurement targets including fabricated features distributed in the selected pattern. The metrology system may further measure the selected attributes for the one or more measurement targets based on regression of the scatterometry data of the one or more measurement targets to the model weighted by the weighting function.

Abstract: A broadband ultraviolet illumination source for a characterization system is disclosed. The broadband ultraviolet illumination source includes an enclosure having one or more walls, the enclosure configured to contain a gas, and a plasma discharge device based on a graphene-dielectric-semiconductor (GOS) planar-type structure. The GOS structure includes a silicon substrate having a top surface, a dielectric layer disposed on the top surface of the silicon substrate, and at least one layer of graphene disposed on a top surface of the dielectric layer. A metal contact may be formed on the top surface of the graphene layer. The GOS structure has several advantages for use in an illumination source, such as low operating voltage (below 50 V), planar surface electron emission, and compatibility with standard semiconductor processes. The broadband ultraviolet illumination source further includes electrodes placed inside the enclosure or magnets placed outside the enclosure to increase the current density.

Abstract: First and second metrology data are used to train a machine-learning model to predict metrology data for a metrology target based on metrology data for a device area. The first metrology data are for a plurality of instances of a device area on semiconductor die fabricated using a fabrication process. The second metrology data are for a plurality of instances of a metrology target that contains structures distinct from structures in the device area. Using the trained machine-learning model, fourth metrology data are predicted for the metrology target based on third metrology data for an instance of the device area. Using a recipe for the metrology target, one or more parameters of the metrology target are determined based on the fourth metrology data. The fabrication process is monitored and controlled based at least in part on the one or more parameters.