Abstract: Multilayer targets enabling fast and accurate, absolute calibration and alignment of X-ray based measurement systems are described herein. The multilayer calibration targets have very high diffraction efficiency and are manufactured using fast, low cost production techniques. Each target includes a multilayer structure built up with pairs of X-ray transparent and X-ray absorbing materials. The layers of the multilayer target structure is oriented parallel to an incident X-ray beam. Measured diffraction patterns indicate misalignment in position and orientation between the incident X-Ray beam and the multilayer target. In another aspect, a composite multilayer target includes at least two multilayer structures arranged adjacent one another along a direction aligned with the incident X-ray beam, adjacent one another along a direction perpendicular to the incident X-ray beam, or a combination thereof. In some embodiments, the multilayer structures are spatially separated from one another by a gap distance.

Abstract: Methods and systems for generating measurement models of nanowire based semiconductor structures based on re-useable, parametric models are presented herein. Metrology systems employing these models are configured to measure structural and material characteristics (e.g., material composition, dimensional characteristics of structures and films, etc.) associated with nanowire semiconductor fabrication processes. The re-useable, parametric models of nanowire based semiconductor structures enable measurement model generation that is substantially simpler, less error prone, and more accurate. As a result, time to useful measurement results is significantly reduced, particularly when modelling complex, nanowire based structures. The re-useable, parametric models of nanowire based semiconductor structures are useful for generating measurement models for both optical metrology and x-ray metrology, including soft x-ray metrology and hard x-ray metrology.

Abstract: An additive-manufacturing head includes: a ring-shape laser beam forming unit having axicon lenses facing each other and a convex lens between the axicon lenses to form a laser beam entering through the axicon lens into a ring-shape laser beam and emit the ring-shape laser beam from the other axicon lens; a lens moving mechanism to move the convex lens in the optical axis direction of the laser beam; a laser beam emitting unit to emit the ring-shape laser beam toward a workpiece; and a material powder feeding tube having an outlet which is disposed inside the ring-shape laser beam emitted from the laser beam emitting unit and from which material powder is released, to feed the material powder from the outlet toward the workpiece. Accordingly, the additive-manufacturing head capable of freely controlling the size of the laser-beam-irradiated region and the laser beam intensity distribution on the workpiece is provided.

Abstract: Methods and systems for creating a measurement model based only on measured training data are presented. The trained measurement model is then used to calculate overlay values directly from measured scatterometry data. The measurement models receive scatterometry signals directly as input and provide overlay values as output. In some embodiments, overlay error is determined from measurements of design rule structures. In some other embodiments, overlay error is determined from measurements of specialized target structures. In a further aspect, the measurement model is trained and employed to measure additional parameters of interest, in addition to overlay, based on the same or different metrology targets. In some embodiments, measurement data from multiple targets, measurement data collected by multiple metrologies, or both, is used for model building, training, and measurement. In some embodiments, an optimization algorithm automates the measurement model building and training process.

Abstract: In some embodiments, a first plurality of electron-microscope images for respective instances of a semiconductor structure is obtained from a first source. The electron-microscope images of the first plurality show different values of one or more semiconductor-fabrication parameters. A model is trained that specifies a relationship between the first plurality of electron-microscope images and the values of the one or more semiconductor-fabrication parameters. A second plurality of electron-microscope images for respective instances of the semiconductor structure on one or more semiconductor wafers is collected. The one or more semiconductor wafers are distinct from the first source. Values of the one or more semiconductor-fabrication parameters for the second plurality of electron-microscope images are predicted using the model.

Abstract: Methods and systems for measuring structural and material characteristics of semiconductor structures based on combined x-ray reflectometry (XRR) and x-ray photoelectron spectroscopy (XPS) are presented herein. A combined XRR and XPS system includes an x-ray illumination source and x-ray illumination optics shared by both the XRR and XPS measurement subsystems. This increases throughput and measurement accuracy by simultaneously collecting XRR and XPS measurement data from the same area of the wafer. A combined XRR and XPS system improves measurement accuracy by employing XRR measurement data to improve measurements performed by the XPS subsystem, and vice-versa. In addition, a combined XRR and XPS system enables simultaneous analysis of both XRR and XPS measurement data to more accurately estimate values of one of more parameters of interest. In a further aspect, any of measurement spot size, photon flux, beam shape, beam diameter, and illumination energy are independently controlled.

Abstract: A parameterized geometric model of a structure can be determined based on spectra from a wafer metrology tool. The structure can have geometry-induced anisotropic effects. Dispersion parameters of the structure can be determined from the parameterized geometric model. This can enable metrology techniques to measure nanostructures that have geometries and relative positions with surrounding structures that induce non-negligible anisotropic effects. These techniques can be used to characterize process steps involving metal and semiconductor targets in semiconductor manufacturing of, for example, FinFETs or and gate-all-around field-effect transistors.

Abstract: Methods and systems for evaluating the performance of multiple patterning processes are presented. Patterned structures are measured and one or more parameter values characterizing geometric errors induced by the multiple patterning process are determined. In some examples, a primary, multiple patterned target is measured and a value of a parameter of interest is directly determined from the measured data by a Signal Response Metrology (SRM) measurement model. In some other examples, a primary, multiple patterned target and an assist target are measured and a value of a parameter of interest is directly determined from the measured data by a Signal Response Metrology (SRM) measurement model. In some other examples, a primary, multiple patterned target is measured at different process steps and a value of a parameter of interest is directly determined from the measured data by a Signal Response Metrology (SRM) measurement model.

Abstract: Methods and systems for more efficient X-Ray scatterometry measurements of on-device structures are presented herein. X-Ray scatterometry measurements of one or more structures over a measurement area includes a decomposition of the one or more structures into a plurality of sub-structures, a decomposition of the measurement area into a plurality of sub-areas, or both. The decomposed structures, measurement areas, or both, are independently simulated. The scattering contributions of each of the independently simulated decomposed structures are combined to simulate the actual scattering of the measured structures within the measurement area. In a further aspect, measured intensities and modelled intensities including one or more incidental structures are employed to perform measurement of structures of interest. In other further aspects, measurement decomposition is employed to train a measurement model and to optimize a measurement recipe for a particular measurement application.

Abstract: A spectroscopic metrology system includes a spectroscopic metrology tool and a controller. The controller generates a model of a multilayer grating including two or more layers, the model including geometric parameters indicative of a geometry of a test layer of the multilayer grating and dispersion parameters indicative of a dispersion of the test layer. The controller further receives a spectroscopic signal of a fabricated multilayer grating corresponding to the modeled multilayer grating from the spectroscopic metrology tool. The controller further determines values of the one or more parameters of the modeled multilayer grating providing a simulated spectroscopic signal corresponding to the measured spectroscopic signal within a selected tolerance. The controller further predicts a bandgap of the test layer of the fabricated multilayer grating based on the determined values of the one or more parameters of the test layer of the fabricated structure.

Abstract: Methods and systems for performing measurements of semiconductor structures based on high-brightness, polychromatic, reflective small angle x-ray scatterometry (RSAXS) metrology are presented herein. RSAXS measurements are performed over a range of wavelengths, angles of incidence, and azimuth angles with small illumination beam spot size, simultaneously or sequentially. In some embodiments, RSAXS measurements are performed with x-ray radiation in the soft x-ray (SXR) region at grazing angles of incidence in the range of 5-20 degrees. In some embodiments, the x-ray illumination source size is 10 micrometers or less, and focusing optics project the source area onto a wafer with a demagnification factor of 0.2 or less, enabling an incident x-ray illumination spot size of less than two micrometers.

Abstract: Methods and systems for positioning a specimen and characterizing an x-ray beam incident onto the specimen in a Transmission, Small-Angle X-ray Scatterometry (T-SAXS) metrology system are described herein. A specimen positioning system locates a wafer vertically and actively positions the wafer in six degrees of freedom with respect to the x-ray illumination beam without attenuating the transmitted radiation. In some embodiments, a cylindrically shaped occlusion element is scanned across the illumination beam while the detected intensity of the transmitted flux is measured to precisely locate the beam center. In some other embodiments, a periodic calibration target is employed to precisely locate the beam center. The periodic calibration target includes one or more spatially defined zones having different periodic structures that diffract X-ray illumination light into distinct, measurable diffraction patterns.

Abstract: Disclosed are apparatus and methods for determining a structure or process parameter value of a target of interest on a semiconductor wafer. A plurality of collection patterns are defined for a spatial light beam controller positioned at a pupil image plane of a metrology tool. For each collection pattern, a signal is collected from a sensor of the metrology tool, and each collected signal represents a combination of a plurality of signals that the spatial light beam controller samples, using each collection pattern, from a pupil image of the target of interest. The collection patterns are selected so that the pupil image is reconstructable based on the collection patterns and their corresponding collection signals. The collected signal for each of the collection patterns is analyzed to determine a structure or process parameter value for the target of interest.

Abstract: Methods and systems for evaluating the geometric characteristics of patterned structures are presented. More specifically, geometric structures generated by one or multiple patterning processes are measured by two or more metrology systems in accordance with a hybrid metrology methodology. A measurement result from one metrology system is communicated to at least one other metrology systems to increase the measurement performance of the receiving system. Similarly, a measurement result from the receiving metrology system is communicated back to the sending metrology system to increase the measurement performance of the sending system. In this manner, measurement results obtained from each metrology system are improved based on measurement results received from other cooperating metrology systems. In some examples, metrology capability is expanded to measure parameters of interest that were previously unmeasurable by each metrology system operating independently.

Abstract: Methods and systems for measuring process induced errors in a multiple patterning semiconductor fabrication process based on measurements of a specimen and process information from one or more previous process steps employed to fabricate the specimen are presented herein. A metrology tool is employed after a number of process steps have been executed. The metrology tool measures structural parameters of interest of metrology targets on the wafer based on measured signals and process information, and communicates correctable process parameter values to one or more process tools involved in the previous process steps. When executed by the appropriate process tool, the correctable process parameter values reduce process induced errors in the geometry of the structures fabricated by the process flow. In another aspect, multiple metrology tools are used to control a fabrication process in combination with process information from one or more process steps in the process flow.

Abstract: Disclosed are apparatus and methods for determining a structure or process parameter value of a target of interest on a semiconductor wafer. A plurality of collection patterns are defined for a spatial light beam controller positioned at a pupil image plane of a metrology tool. For each collection pattern, a signal is collected from a sensor of the metrology tool, and each collected signal represents a combination of a plurality of signals that the spatial light beam controller samples, using each collection pattern, from a pupil image of the target of interest. The collection patterns are selected so that the pupil image is reconstructable based on the collection patterns and their corresponding collection signals. The collected signal for each of the collection patterns is analyzed to determine a structure or process parameter value for the target of interest.

Abstract: Disclosed are apparatus and methods for determining a structure or process parameter value of a target of interest on a semiconductor wafer. A plurality of collection patterns are defined for a spatial light beam controller positioned at a pupil image plane of a metrology tool. For each collection pattern, a signal is collected from a sensor of the metrology tool, and each collected signal represents a combination of a plurality of signals that the spatial light beam controller samples, using each collection pattern, from a pupil image of the target of interest. The collection patterns are selected so that the pupil image is reconstructable based on the collection patterns and their corresponding collection signals. The collected signal for each of the collection patterns is analyzed to determine a structure or process parameter value for the target of interest.

Abstract: An inspection system is provided that can include a reflectometer having a light source for projecting light, and a light splitter for receiving the light projected by the light source, transforming at least one aspect of the light, and projecting the light once transformed. The reflectometer further has an off-axis unobscured objective lens through which the light transformed by the light splitter passes to contact a fabricated component, and has a detector for detecting a result of the transformed light contacting the fabricated component. The inspection system can additionally, or alternatively, include an ellipsometer having a light source similar to the reflectometer, and further a polarizing element to polarize the light of the light splitter. The polarized light passes through an off-axis unobscured objective lens to contact a fabricated component, and a detector detects a result of the polarized light contacting the fabricated component.

Abstract: Methods and systems for evaluating the performance of multiple patterning processes are presented. Patterned structures are measured and one or more parameter values characterizing geometric errors induced by the multiple patterning process are determined. In some examples, a primary, multiple patterned target is measured and a value of a parameter of interest is directly determined from the measured data by a Signal Response Metrology (SRM) measurement model. In some other examples, a primary, multiple patterned target and an assist target are measured and a value of a parameter of interest is directly determined from the measured data by a Signal Response Metrology (SRM) measurement model. In some other examples, a primary, multiple patterned target is measured at different process steps and a value of a parameter of interest is directly determined from the measured data by a Signal Response Metrology (SRM) measurement model.

Abstract: Electromagnetic modeling of finite structures and finite illumination for metrology and inspection are described herein. In one embodiment, a method for evaluating a diffracting structure involves providing a model of the diffracting structure. The method involves computing background electric or magnetic fields of an environment of the diffracting structure. The method involves computing scattered electric or magnetic fields from the diffracting structure using a scattered field formulation based on the computed background fields. The method further involves computing spectral information for the model of the diffracting structure based on the computed scattered fields, and comparing the computed spectral information for the model with measured spectral information for the diffracting structure. In response to a good model fit, the method involves determining a physical characteristic of the diffracting structure based on the model of the diffracting structure.