Abstract: Systems configured to provide illumination for wafer inspection performed by a wafer inspection tool are provided. One system includes one or more pupil lenses configured to focus a first far field pattern having a shape different than a shape of light generated by a light source. The system also includes a field lens array positioned between the one or more pupil lenses and an aperture stop. In addition, the system includes a lens group configured to focus a second far field pattern generated by the field lens array to a back focal plane of the lens group. The back focal plane of the lens group is a field plane of a wafer inspection tool at which a wafer to be inspected is placed during wafer inspection.

Abstract: A system and method for local film stress calculation is disclosed. The method may include specifying a plurality of measurement points on a substrate, the substrate being configured to receive a film deposition; obtaining a local film thickness measurement for each measurement point; obtaining a local wafer shape parameter for each measurement point; and calculating a local film stress value for each measurement point based on the local film thickness measurement and the local wafer shape parameter for each corresponding measurement point. The method may further include specifying a plurality of estimation points on the substrate; obtaining a local wafer shape parameter for each estimation point; calculating an estimated local film thickness for each estimation point; and calculating a local film stress value for each estimation point based on the estimated local film thickness and the local wafer shape parameter for each corresponding estimation point.

Abstract: Methods and systems for source multiplexing illumination for mask inspection are disclosed. Such illumination systems enable EUV sources of small brightness to be used for EUV mask defect inspection at nodes below the 22 nm. Utilizing the multiple plane or conic mirrors that are either attached to a continuously rotating base with different angles or individually rotating to position for each pulse, the reflected beams may be directed through a common optical path. The light may then be focused by a condenser to an EUV mask. The reflected and scattered light from the mask may then be imaged by some imaging optics onto some sensors. The mask image may be subsequently processed for defect information.

Abstract: A method for improving computation efficiency for diffraction signals in optical metrology is described. The method includes simulating a set of diffraction orders for a three-dimensional structure. The diffraction orders within the set of diffraction orders are then prioritized. The set of diffraction orders is truncated to provide a truncated set of diffraction orders based on the prioritizing. Finally, a simulated spectrum is provided based on the truncated set of diffraction orders.

Abstract: Metrology targets, optical systems and methods are provided, which enable metrology measurements of very small features, using resonance of illuminated radiation within periodical structures of the target, under appropriate illumination. Metrology targets comprise periodical structure(s) configured to resonate incident radiation and having a pitch defined by the grating equation with respect to configured parameters such as the selected diffraction order, refractive indices and the illumination's wavelength(s) and incidence angles. Possibly, the target may further comprise substructure(s) which are optically coupled with the resonating incident radiation in the periodical structure(s).

Abstract: A system for inspecting a sample including a detector, either a photomultiplier tube or an electron-bombarded image sensor, that is positioned to receive light from the sample. The detector includes a semiconductor photocathode and a photodiode. Notably, the photodiode includes a p-doped semiconductor layer, an n-doped semiconductor layer formed on a first surface of the p-doped semiconductor layer to form a diode, and a pure boron layer formed on a second surface of the p-doped semiconductor layer. The semiconductor photocathode includes silicon, and further includes a pure boron coating on at least one surface.

Abstract: The present invention may include performing a first measurement on a wafer of a first lot of wafers via an omniscient sampling process, calculating a first set of process tool correctables utilizing one or more results of the measurement performed via an omniscient sampling process, randomly selecting a set of field sampling locations of the wafer of a first lot of wafers, calculating a second set of process tool correctables by applying an interpolation process to the randomly selected set of field sampling locations, wherein the interpolation process utilizes values from the first set of process tool correctables for the randomly selected set of field sampling locations in order to calculate correctables for fields of the wafer of the first lot not included in the set of randomly selected fields, and determining a sub-sampling scheme by comparing the first set of process tool correctables to the second set of correctables.

Abstract: Some aspects of the present disclosure relate to a system having a substrate device, a substrate support surface, and a substrate handler that positions the substrate device on the substrate support surface. The substrate device and the substrate support surface may have counterpart coarse position units and fine position units. The system may measure coarse positional offsets between the first and second coarse position units, re-position the substrate device on the substrate support surface based on the coarse positional offsets, and subsequently measure fine positional offsets between the first and second fine position units. In some implementations, the substrate device is integrally coupled to the substrate handler via a wireless communication link in order to communicate position information as feedback for further placement.

Abstract: End effectors of reticle mechanical interface pods as well as reticle handling methods are provided, which handle the reticle by the end effector by applying a lateral force and/or a downward force on the reticle during the handling to fixate the reticle to at least two supports (e.g., at least four fingers) which are attached to at least two arms of the end effector and are configured to apply an upwards force on the reticle. Hence the reticle is fixated to the end effector and can be handled with higher accelerations and at a higher throughput than current methods. End effectors may have multiple fingers to fixate the reticle, and on more pushers may apply a downwards force to further fixate the reticle to the supports.

Abstract: A high sensitivity image sensor comprises an epitaxial layer of silicon that is intrinsic or lightly p doped (such as a doping level less than about 1013 cm?3). CMOS or CCD circuits are fabricated on the front-side of the epitaxial layer. Epitaxial p and n type layers are grown on the backside of the epitaxial layer. A pure boron layer is deposited on the n-type epitaxial layer. Some boron is driven a few nm into the n-type epitaxial layer from the backside during the boron deposition process. An anti-reflection coating may be applied to the pure boron layer. During operation of the sensor a negative bias voltage of several tens to a few hundred volts is applied to the boron layer to accelerate photo-electrons away from the backside surface and create additional electrons by an avalanche effect. Grounded p-wells protect active circuits as needed from the reversed biased epitaxial layer.

Abstract: Methods and systems for detecting defects on a wafer are provided. One method includes determining difference values for pixels in first output for a wafer generated using a first optics mode of an inspection system and determining other values for pixels in second output for the wafer generated using a second optics mode of the inspection system. The first and second optics modes are different from each other. The method also includes generating a two-dimensional scatter plot of the difference values and the other values for the pixels in the first and second output corresponding to substantially the same locations on the wafer. The method further includes detecting defects on the wafer based on the two-dimensional scatter plot.

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: Disclosed are methods and apparatus for inspecting a vertical memory stack. On an inspection tool, incident light having a first wavelength range is used to detect defects on a surface of the vertical memory stack. On the inspection tool, incident light having a second wavelength range is used to detect defects on both the surface and throughout a depth of the vertical memory stack. The defects detected using the first and second wavelength range are compared to detect defects only throughout the depth of the vertical memory stack, excluding defects on the surface, as well as to detect defects only on the surface.

Abstract: Methods and systems for setting up a classifier for defects detected on a wafer are provided. One method includes generating a template for a defect classifier for defects detected on a wafer and applying the template to a training data set. The training data set includes information for defects detected on the wafer or another wafer. The method also includes determining one or more parameters for the defect classifier based on results of the applying step.

Abstract: An inspection system that receives image data corresponding to an image and processes the image data to produce a report corresponding to characteristics of the image. Interface cards receive the image data in a flow, where each interface card receives image data corresponding to a different portion of the image. Process nodes connect to the interface cards, and receive the image data from the interface cards. A host computer is connected to the process nodes, and job managers implemented in the host computer manage the flow of image data to and from the process nodes. The job managers remain operable during a crash of one of the process nodes. Process node programs are implemented in the process nodes, and analyze a portion of the image data and produce the report corresponding to the characteristics of the analyzed portion of the image data. At least one process node program is implemented in each process node. The process node programs rapidly analyze the image.

Abstract: A system for forming a laser-sustained plasma includes a gas containment element, an illumination source configured to generate pump illumination, and a collector element. The gas containment element is configured to contain a volume of a gas mixture. The collector element is configured to focus the pump illumination from the pumping source into the volume of the gas mixture contained within the gas containment element in order to generate a plasma within the volume of the gas mixture that emits broadband radiation. The gas mixture filters one or more selected wavelengths of radiation emitted by the plasma.

Abstract: Disclosed are methods and apparatus for qualifying a photolithographic reticle. A reticle inspection tool is used to acquire at least two images at different imaging configurations from each pattern area of the reticle. A reticle pattern is reconstructed based on each at least two images from each pattern area of the reticle. For each reconstructed reticle pattern, a lithographic process with two or more different process conditions is modeled on such reconstructed reticle pattern to generate two or more corresponding modeled test wafer patterns. Each two or more modelled test wafer patterns is analyzed to identify hot spot patterns of the reticle patterns that are susceptible to the different process conditions altering wafer patterns formed with such hot spot patterns.

Abstract: Inspection with multiple illumination regions includes generating a primary beam of illumination directed along a primary illumination direction, transmitting a portion of the primary beam of illumination along a first illumination direction, deflecting a portion of the primary beam of illumination along a second illumination direction different from the first illumination direction with one or more angular selection elements, focusing the transmitted portion of the primary beam of illumination onto a first inspection region of the substrate, and focusing the deflected portion of the primary beam of illumination onto a second inspection region of the substrate being spatially separated from the first inspection region.

Abstract: A moving wafer imaging system processes wafer images to remove motion and focus blur by performing a blind deconvolution to determine an approximate point spread function. The approximate point spread function, estimated image noise and a Gaussian point spread function are used to compute a weighted point spread function. The weighted point spread function is used to filter out motion focus blur. Noise is then removed with a low-pass filter.

Abstract: One embodiment relates to an apparatus for aberration correction in an electron beam lithography system. An inner electrode surrounds a pattern generating device, and there is at least one outer electrode around the inner electrode. Each of the inner and outer electrodes has a planar surface in a plane of the pattern generating device. Circuitry is configured to apply an inner voltage level to the inner electrode and at least one outer voltage level to the at least one outer electrode. The voltage levels may be set to correct a curvature of field in the electron beam lithography system. Another embodiment relates to an apparatus for aberration correction used in an electron based system, such as an electron beam inspection, or review, or metrology system. Other embodiments, aspects and features are also disclosed.