Abstract: One embodiment relates to a method of detecting a buried defect in a target microscopic metal feature. An imaging apparatus is configured to impinge charged particles with a landing energy such that the charged particles, on average, reach a depth within the target microscopic metal feature. In addition, the imaging apparatus is configured to filter out secondary electrons and detect backscattered electrons. The imaging apparatus is then operated to collect the backscattered electrons emitted from the target microscopic metal feature due to impingement of the charged particles. A backscattered electron (BSE) image of the target microscopic metal feature is compared with the BSE image of a reference microscopic metal feature to detect and classify the buried defect. Other embodiments, aspects and features are also disclosed.

Abstract: Embodiments of this invention use multi-layer ceramic substrate with one or more hermetically sealed and filled metal vias with smaller pitch and size in combination with flexible printed circuit cables and interposers to provide a custom electric feed through for vacuum to atmosphere chambers. This abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: A mode-locked laser system operable at low temperature can include an annealed, frequency-conversion crystal and a housing to maintain an annealed condition of the crystal during standard operation at the low temperature. In one embodiment, the crystal can have an increased length. First beam shaping optics can be configured to focus a beam from a light source to an elliptical cross section at a beam waist located in or proximate to the crystal. A harmonic separation block can divide an output from the crystal into beams of different frequencies separated in space. In one embodiment, the mode-locked laser system can further include second beam shaping optics configured to convert an elliptical cross section of the desired frequency beam into a beam with a desired aspect ratio, such as a circular cross section.

Abstract: A calibration wafer and a method for calibrating an interferometer system are disclosed. The calibration method includes: determining locations of the holes defined in the calibration wafer based on two opposite intensity frame; comparing the locations of the holes against the locations measured utilizing an external measurement device; adjusting a first optical magnification or a second optical magnification at least partially based on the comparison result; defining a distortion map for each of the first and second intensity frames based on the comparison of the locations of the holes; generating an extended distortion map for each of the first and second intensity frames by map fitting the distortion map; and utilizing the extended distortion map for each of the first and second intensity frames to reduce at least one of: a registration error or an optical distortion in a subsequent measurement process.

Abstract: A sensor apparatus for measuring a plasma process parameter for processing a workpiece. The sensor apparatus includes a base, an information processor supported on or in the base, and at least one sensor supported on or in the base. The at least one sensor includes at least one sensing element configured for measuring an electrical property of a plasma and may include a transducer coupled to the at least one sensing element. The transducer can be configured to receive a signal from the sensing element and convert the signal into a second signal for input to the information processor.

Abstract: The present disclosure is directed to a system for protecting a reflective optic and/or any other surface in a plasma-based illumination system from debris by actively flowing gas against the debris flow direction. According to various embodiments, a vacuum chamber is configured to contain a target material, wherein a laser or discharge produced plasma is generated in response to an excitation of the target material. One or more outlets within the chamber are configured to receive gas flowing from a fluidically coupled gas source and further configured to actively flow the gas towards a source of debris and away from the reflective optic or any other protected surface at a controlled flow rate.

Abstract: Optical inspection methods and apparatus for high-resolution photomasks using only a test image. A filter is applied to an image signal received from radiation that is transmitted by or reflected from a photomask having a test image. The filter may be implemented using programmed control to adjust and control filter conditions, illumination conditions, and magnification conditions.

Abstract: The passivation of a nonlinear optical crystal for use in an inspection tool includes growing a nonlinear optical crystal in the presence of at least one of fluorine, a fluoride ion and a fluoride-containing compound, mechanically preparing the nonlinear optical crystal, performing an annealing process on the nonlinear optical crystal and exposing the nonlinear optical crystal to a hydrogen-containing or deuterium-containing passivating gas.

Abstract: Methods and systems for design based sampling and binning for yield critical defects are provided. One method includes aligning each image patch in each inspection image frame generated for a wafer by an optical subsystem of an inspection system to design information for the wafer. The method also includes deriving multiple layer design attributes at locations of defects detected in the image patches. In addition, the method includes building a decision tree with the multiple layer design attributes. The decision tree is used to separate the defects into bins with different yield impacts on a device being formed on the wafer. The method also includes binning the defects with the decision tree.

Abstract: One embodiment relates to an electron beam apparatus which includes a dual-lens electron gun for emitting an electron beam. The electron beam is a high beam-current electron beam in a first operating mode and a low beam-current electron beam in a second operating mode. The apparatus further includes a column aperture which is out of the path of the high beam-current electron beam in the first operating mode and is centered about an optical axis of the electron beam apparatus in the second operating mode. Another embodiment relates to an electron gun which includes a first gun lens, a beam limiting aperture, and a second gun lens. The first gun lens focuses the electrons before they pass through the beam-limiting aperture while the second gun lens focuses the electrons after they pass through the beam-limiting aperture. Other embodiments, aspects and features are also disclosed.

Abstract: Methods and systems for adaptive sampling for semiconductor inspection recipe creation, defect review, and metrology are provided. The embodiments provide image processing and pattern recognition algorithms and an adaptive sampling method for extracting critical areas from SEM image patches for use in a wafer inspection system when design data for a semiconductor chip is not available. The embodiments also provide image processing and pattern recognition algorithms for efficiently discovering critical defects and significant deviations in the normal manufacturing process, using the output from a wafer inspection system and an adaptive sampling method to select wafer locations to be examined on a high resolution review or metrology tool.

Abstract: Disclosed are methods and apparatus for inspecting a vertical semiconductor stack of a plurality of layers is disclosed. The method includes (a) on a confocal tool, repeatedly focusing an illumination beam at a plurality of focus planes at a plurality of different depths of a first vertical stack, wherein a defect is located at an unknown one of the different depths and the illumination beam has a wavelength range between about 700 nm and about 950 nm, (b) generating a plurality of in-focus images for the different depths based on in-focus output light detected from the first vertical stack at the different depths, wherein out-of-focus output light is inhibited from reaching the detector of the confocal system and inhibited from contributing to generation of the in-focus images, and (c) determining which one of the different depths at which the defect is located in the first vertical stack based on the in-focus images.

Abstract: Systems and methods for classifying defects on a wafer are provided. One method includes dilating an extended bounding box (EBB) surrounding a defect position on a wafer in two dimensions in proportion to a width and height of a pattern of interest (POI) for a hot spot closest to the defect position. The method also includes determining if polygons in the POI match polygons in the dilated bounding box. If the polygons in the POI do not match the polygons in the dilated bounding box, the defect is classified as a non-hot spot defect. If the polygons in the POI match the polygons in the dilated bounding box, the defect is classified as a hot spot defect if the area of the EBB intersects the area of interest associated with the hot spot and a non-hot spot defect if the EBB area does not intersect the area of interest.

Abstract: Inline yield monitoring may include the use of one or more modules of algorithmic software. Inline yield monitoring may include the use of two related algorithmic software modules such as a learning and a prediction module. The learning module may learn critical PET (parametric electrical test) parameters from data of probe electrical test yields and PET attribute values. The critical PET parameters may best separate outliers and inliers in the yield data. The prediction module may use the critical PET parameters found by the learning module to predict whether a wafer is an inlier or an outlier in a probe test classification.

Abstract: Methods and systems for dynamic design attributes for wafer inspection are provided. One method includes, at run time of a wafer inspection recipe, prompting a user of a wafer inspection tool on which the wafer inspection recipe is performed for information for a design based binning (DBB) process. The information includes one or more formulae for calculating design attributes from a design for a wafer. The design attributes are used to bin the defects in the DBB process. The method also includes performing inspection of a wafer according to an updated wafer inspection recipe. Performing the inspection includes binning defects detected on the wafer according to the DBB process in the updated wafer inspection recipe.

Abstract: One embodiment relates to an oblique illuminator. The oblique illuminator includes a light source emitting a light beam, a first reflective surface, and a second reflective surface. The first reflective surface has a convex cylindrical shape with a projected parabolic profile along the non-powered direction which is configured to reflect the light beam from the light source and which defines a focal line. The second reflective surface has a concave cylindrical shape with a projected elliptical profile which is configured to reflect the light beam from the first reflective surface and which defines first and second focal lines. The focal line of the first reflective surface is coincident with the first focal line of the second reflective surface. The first and second focal lines of the second reflective surface may be a same line in which case the elliptical curvature is a projected spherical profile. Other embodiments, aspects and features are also disclosed.

Abstract: A detection method for a spot image based thin line detection is disclosed. The method includes a step for generating a band limited spot image from a transmitted and reflected optical image of the mask. The spot image is calibrated to minimize a plurality of optical aberrations from the spot image. The spot image is restored back to a mask image to allow at least one of: a more reliable segmentation between thin line and non-thin line areas on the mask image or a more accurate line width measurement for facilitating segmentation. Thin line features and non-thin lines features are distinguished on the restored mask image. Areas containing thin line features are grown while preventing the thin line growth from encroaching the non-thin line features.

Abstract: A laser-sustained plasma illuminator system includes at least one laser light source to provide light. At least one reflector focuses the light from the laser light source at a focal point of the reflector. An enclosure substantially filled with a gas is positioned at or near the focal point of the reflector. The light from the laser light source at least partially sustains a plasma contained in the enclosure. The enclosure has at least one wall with a thickness that is varied to compensate for optical aberrations in the system.

Abstract: Methods and systems for creating a measurement model based on measured training data are presented. The trained measurement model is used to calculate process parameter values, structure parameter values, or both, directly from measured data collected from other wafers. The measurement models receive measurement data directly as input and provide process parameter values, structure parameter values, or both, as output. The measurement model enables the direct measurement of process parameters. Measurement data from multiple targets is collected for model building, training, and measurement. In some examples, the use of measurement data associated with multiple targets eliminates, or significantly reduces, the effect of under layers in the measurement result, and enables more accurate measurements. Measurement data collected for model building, training, and measurement, may be derived from measurements performed by a combination of multiple, different measurement techniques.

Abstract: A system for controlling convective flow in a light-sustained plasma includes an illumination source configured to generate illumination, a plasma cell including a bulb for containing a volume of gas, a collector element arranged to focus illumination from the illumination source into the volume of gas in order to generate a plasma within the volume of gas contained within the bulb. Further, the plasma cell is disposed within a concave region of the collector element, where the collector element includes an opening for propagating a portion of a plume of the plasma to a region external to the concave region of the collect element.