Abstract: Methods and systems for detecting and classifying defects on a specimen are provided. One system includes one or more components executed by one or more computer subsystems. The one or more components include a neural network configured for detecting defects on a specimen and classifying the defects detected on the specimen. The neural network includes a first portion configured for determining features of images of the specimen generated by an imaging subsystem. The neural network also includes a second portion configured for detecting defects on the specimen based on the determined features of the images and classifying the defects detected on the specimen based on the determined features of the images.

Abstract: Systems and methods for detecting defects on a wafer are provided. One method includes generating output for a wafer by scanning the wafer with an inspection system using first and second optical states of the inspection system. The first and second optical states are defined by different values for at least one optical parameter of the inspection system. The method also includes generating first image data for the wafer using the output generated using the first optical state and second image data for the wafer using the output generated using the second optical state. In addition, the method includes combining the first image data and the second image data corresponding to substantially the same locations on the wafer thereby creating additional image data for the wafer. The method further includes detecting defects on the wafer using the additional image data.

Abstract: Methods and systems for matching measurement spectra across one or more optical metrology systems are presented. The values of one or more system parameters used to determine the spectral response of a specimen to a measurement performed by a target metrology system are optimized. The system parameter values are optimized such that differences between measurement spectra generated by a reference system and the target system are minimized for measurements of the same metrology targets. Methods and systems for matching spectral errors across one or more optical metrology systems are also presented. A trusted metrology system measures the value of at least one specimen parameter to minimize model errors introduced by differing measurement conditions present at the time of measurement by the reference and target metrology systems. Methods and systems for parameter optimization based on low-order response surfaces are presented to reduce the compute time required to refine system calibration parameters.

Abstract: Electron source designs are disclosed. The emitter structure, which may be silicon, has a layer on it. The layer may be graphene or a photoemissive material, such as an alkali halide. An additional layer between the emitter structure and the layer or a protective layer on the layer can be included. Methods of operation and methods of manufacturing also are disclosed.

Abstract: Methods and systems for training a neural network for defect detection in low resolution images are provided. One system includes an inspection tool that includes high and low resolution imaging subsystems and one or more components that include a high resolution neural network and a low resolution neural network. Computer subsystem(s) of the system are configured for generating a training set of defect images. At least one of the defect images is generated synthetically by the high resolution neural network using an image generated by the high resolution imaging subsystem. The computer subsystem(s) are also configured for training the low resolution neural network using the training set of defect images as input. In addition, the computer subsystem(s) are configured for detecting defects on another specimen by inputting the images generated for the other specimen by the low resolution imaging subsystem into the trained low resolution neural network.

Abstract: The disclosure is directed to providing visual feedback for inspection algorithms and difference filters used to process test and reference images from an inspection system. A user interface may be configured for displaying information and accepting user commands. A computing system communicatively coupled to the user interface may be configured to receive at least one set of test and reference images collected by the inspection system. The computing system may be further configured to provide at least one visual representation of the test and reference images via the user interface to show effects of an inspection algorithm and/or difference filter.

Abstract: Information from metrology tools can be used during inspection or review with a scanning electron microscope. Metrology measurements of a wafer are interpolated and/or extrapolated over a field, which creates modified metrology data. The modified metrology data is associated with defect attributes from inspection measurements of a wafer. A wafer review sampling plan is generated based on the defect attributes and the modified metrology data. The wafer review sampling plan can be used during review of a wafer using the scanning electron microscope.

Abstract: Systems and methods of a two-pass inspection methodology that dynamically creates micro care areas for inspection of repeater defects. Micro care areas can be formed around each location of a repeater defect. After inspection, additional repeater defects in the micro care areas can be identified. Attributes of the repeater defects can be compared and any repeater defects with attributes that deviate from an expected group attribute distribution can be classified as nuisance.

Abstract: Methods and systems are disclosed that provide nuisance reduction in images, such as semiconductor images that include one or more metal lines. A potential defect is correlated against pixel grey level intensity charts for two perpendicular axes. A position of the potential defect relative to a pattern, such as a metal line, is determined along the two axes. The potential defect can be classified as a defect of interest or nuisance event.

Abstract: Metal film thickness can be determined using the sheet resistance, resistivity, and temperature coefficient of resistivity for the metal film. Variation in film thickness measurements caused by resistivity can be reduced or eliminated. A probe head may be used for some of the measurements of the metal film. The probe head can include a temperature sensor used during sheet resistance measurements. A wafer on a chuck is heated, such as using the chuck or the probe head, for the measurements.

Abstract: Metrology methods, systems and targets are provided, which implement a side by side paradigm. Adjacent cells with periodic structures are used to extract the overlay error, e.g., by introducing controllable phase shifts or image shifts which enable algorithmic computation of the overlay. The periodic structures are designed to exhibit a rotational symmetry to support the computation and reduce errors.

Abstract: A system includes a controller with one or more processors and memory configured to store one or more sets of program instructions. The one or more processors are configured to execute the one or more sets of program instructions. The one or more sets of program instructions are configured to cause the one or more processors to apply filtering to a semiconductor wafer map; separate the filtered semiconductor wafer map into a plurality of dies; generate a set of die comparison statistics for the plurality of dies; generate at least one excursion map by applying at least one inspection threshold to the set of die comparison statistics; and detect at least one excursion within the at least one excursion map.

Abstract: Metrology targets and target design methods are provided, in which target elements are defined by replacing elements from a periodic pattern having a pitch p, by assist elements having at least one geometric difference from the replaced elements, to form a composite periodic structure that maintains the pitch p as a single pitch. Constructing targets within the bounds of compatibility with advanced multiple patterning techniques improves the fidelity of the targets and fill factor modulation enables adjustment of the targets to produce sufficient metrology sensitivity for extracting the overlay while achieving process compatibility of the targets.

Abstract: Wafer geometry measurement tools and methods for providing improved wafer geometry measurements are disclosed. Wafer front side, backside and flatness measurements are taken into consideration for semiconductor process control. The measurement tools and methods in accordance with embodiments of the present disclosure are suitable for handling any types of wafers, including patterned wafers, without the shortcomings of conventional metrology systems.

Abstract: Metrology methods and targets are provided, that expand metrological procedures beyond current technologies into multi-layered targets, quasi-periodic targets and device-like targets, without having to introduce offsets along the critical direction of the device design. Several models are disclosed for deriving metrology data such as overlays from multi-layered target and corresponding configurations of targets are provided to enable such measurements. Quasi-periodic targets which are based on device patterns are shown to improve the similarity between target and device designs, and the filling of the surroundings of targets and target elements with patterns which are based on device patterns improve process compatibility. Offsets are introduced only in non-critical direction and/or sensitivity is calibrated to enable, together with the solutions for multi-layer measurements and quasi-periodic target measurements, direct device optical metrology measurements.

Abstract: A mechanical testing system having a frame, and a stage for holding a sample. An arm for pressing a tool against a surface of the sample. A primary actuator is connected to the frame and applies a primary force and drives the tool relative to the sample, thereby causing the frame to flex. A displacement sensor measures a displacement value comprised of two components, the first component including a distance traveled by the probe into the sample as the primary force is applied, and the second component including a measure of a degree of flex of the frame as the primary force is applied. A compensating actuator is connected to the frame and applies a compensating force that reduces the second component of the displacement value.

Abstract: A system includes one or more wafer geometry measurement tools configured to obtain geometry measurements from a wafer. The system also includes one or more processors in communication with the one or more wafer geometry measurement tools. The one or more processors are configured to apply a correction model to correct the geometry measurements obtained by the one or more wafer geometry measurement tools. The correction model is configured to correct measurement errors caused by a transparent film positioned on the wafer.

Abstract: A method may include, but is not limited to, receiving a plurality of reference images of a wafer. The method may include, but is not limited to, receiving the plurality of test images of the wafer. The method may include, but is not limited to, aligning the plurality of reference images and the plurality of test images via a coarse alignment process. The method may include, but is not limited to, aligning the plurality of reference images and the plurality of test images via a fine alignment process after alignment via the coarse alignment process. The fine alignment process may include measuring individual offsets and correcting individual offset data between at least one of the plurality of reference images and the plurality of test images.

Abstract: Systems and methods for determining information for defects on a wafer are provided. One system includes an illumination subsystem configured to direct light having one or more illumination wavelengths to a wafer. The one or more illumination wavelengths are selected to cause fluorescence from one or more materials on the wafer without causing fluorescence from one or more other materials on the wafer. The system also includes a detection subsystem configured to detect only the fluorescence from the one or more materials or to detect non-fluorescent light from the wafer without detecting the fluorescence from the one or more materials. In addition, the system includes a computer subsystem configured to determine information for defects on the wafer using output generated by the detection subsystem responsive to the detected fluorescence or the detected non-fluorescent light.

Abstract: A system for generating pump illumination for laser sustained plasma (LSP) is disclosed. In embodiments, the system includes an illumination source configured to output illumination having a first spectral frequency and an optical frequency converter. The optical frequency converter can be configured to receive the illumination having the first spectral frequency from the illumination source and configured to output pump illumination having a second spectral frequency that is different from the first spectral frequency.