Chucking warped wafer with bellows
Granted: May 1, 2018
Patent Number:
9960070
A vacuum chuck has at least one suction assembly that pulls a wafer surface toward a chucking surface. The suction assembly may be used with a wafer that is warped. A suction force engages a pad of a suction assembly with the wafer surface and retracts a bellows of the suction assembly. As the bellows retracts and draws the wafer surface closer to the chucking surface, the suction force provided by the vacuum chuck can pull the wafer flat.
Scanning in angle-resolved reflectometry and algorithmically eliminating diffraction from optical metrology
Granted: May 1, 2018
Patent Number:
9958385
Angle-resolved reflectometers and reflectometry methods are provided, which comprise a coherent light source, an optical system arranged to scan a test pattern using a spot of coherent light from the light source to yield realizations of the light distribution in the collected pupil, wherein the spot covers a part of the test pattern and the scanning is carried out optically or mechanically according to a scanning pattern, and a processing unit arranged to generate a composite image of…
Increasing dynamic range of a height sensor for inspection and metrology
Granted: May 1, 2018
Patent Number:
9958257
A system includes a first beam splitter, a second beam splitter, and a mirror. The second beam splitter can produce two lines of light, which are received by at least one sensor. The two lines of light have different focal heights on the wafer. A distance between the second beam splitter and the mirror can be configured to change a focal height on the wafer. A height of an illuminated region on a surface of the wafer relative to a normal surface of the wafer can be determined using the…
Small spot size spectroscopic ellipsometer
Granted: April 24, 2018
Patent Number:
9952140
Methods and systems for small angle CD metrology with a small spot size are introduced to increase measurement sensitivity while maintaining adequate throughput necessary for modern semiconductor manufacture. A small angle CD metrology system includes a small angle spectroscopic ellipsometry (SE) subsystem combined with a small angle spectroscopic reflectometry system, both operated at small angles of incidence. The small angle SE subsystem is configured to operate in a complete Mueller…
Range-based real-time scanning electron microscope non-visual binner
Granted: April 17, 2018
Patent Number:
9947596
A technique to identify non-visual defects, such as SEM non-visual defects (SNVs), includes generating an image of a layer of a wafer, evaluating at least one attribute of the image using a classifier, and identifying the non-visual defects on the layer of the wafer. A controller can be configured to identify the non-visual defects using the classifier. This controller can communicate with a defect review tool, such as a scanning electron microscope (SEM).
Generating an array of spots on inclined surfaces
Granted: April 17, 2018
Patent Number:
9945792
A system which may be used to generate a plurality of spots on a surface is provided. The spots may be aligned with the incident plane of oblique illumination. The system may include a diffractive optical element configured to split a beam into a plurality of beams by generating a plurality of diffraction orders. The system may also include a focusing lens configured to focus at least some of the plurality of beams on the surface in the plurality of spots. At least some of the plurality…
High power broadband light source
Granted: April 10, 2018
Patent Number:
9941655
A system for generating high power broadband light includes multiple light-sustained plasma light sources. Each one of the light-sustained sources includes a pumping source, a gas containment structure for containing gas and configured to receive pumping illumination from the pumping source and a parabolic reflector element arranged to collect at least a portion of the broadband radiation emitted by the generated plasma and form a collimated broadband radiation output. The system also…
Bias-variant photomultiplier tube
Granted: April 10, 2018
Patent Number:
9941103
A bias-variant photomultiplier tube (PMT) includes a photocathode that when operating absorbs photons and emits photoelectrons responsive to the absorbed photons. The bias-variant PMTO also includes a plurality of dynodes that receive the photoelectrons emitted by the photocathode. The plurality of dynodes include a first pair of dynodes having a first bias difference and at least a second pair of dynodes having a second bias difference. The second bias difference is greater than the…
System, method and computer program product for detecting defects in a fabricated target component using consistent modulation for the target and reference components
Granted: April 10, 2018
Patent Number:
9940705
A fabricated device having consistent modulation between target and reference components is provided. The fabricated device includes a target component having a first modulation. The fabricated device further includes at least two reference components for the target component including a first reference component and a second reference component, where the first reference component and the second reference component each have the first modulation. Further, a system, method, and computer…
193nm laser and inspection system
Granted: April 3, 2018
Patent Number:
9935421
An improved solid-state laser for generating sub-200 nm light is described. This laser uses a fundamental wavelength between about 1030 nm and 1065 nm to generate the sub-200 nm light. The final frequency conversion stage of the laser creates the sub-200 nm light by mixing a wavelength of approximately 1109 nm with a wavelength of approximately 234 nm. By proper selection of non-linear media, such mixing can be achieved by nearly non-critical phase matching. This mixing results in high…
Extractor electrode for electron source
Granted: April 3, 2018
Patent Number:
9934933
Extractors and extractor systems minimize the generation of secondary electrons which interact with and degrade the primary electron beam. This can improve the performance of an electron beam system, such as a scanning electron microscope. The extractor may include a frustoconical aperture that widens as distance from the source of the electron beam increases. The entrance into the frustoconical aperture also can include a curved edge.
Focus measurements using scatterometry metrology
Granted: April 3, 2018
Patent Number:
9934353
Target designs and methods are provided, which relate to periodic structures having elements recurring with a first pitch in a first direction. The elements are periodic with a second pitch along a second direction that is perpendicular to the first direction and are characterized in the second direction by alternating, focus-sensitive and focus-insensitive patterns with the second pitch. In the produced targets, the first pitch may be about the device pitch and the second pitch may be…
Multi-layer overlay metrology target and complimentary overlay metrology measurement systems
Granted: March 27, 2018
Patent Number:
9927718
A multi-layer overlay target for use in imaging based metrology is disclosed. The overlay target includes a plurality of target structures including three or more target structures, each target structure including a set of two or more pattern elements, wherein the target structures are configured to share a common center of symmetry upon alignment of the target structures, each target structure being invariant to N degree rotation about the common center of symmetry, wherein N is equal…
Confocal line inspection optical system
Granted: March 27, 2018
Patent Number:
9927371
A line scan wafer inspection system includes a confocal slit aperture filter to remove sidelobes and enhance resolution in the scanning direction. A position detector associated with the slit aperture filter monitors and corrects illumination line image positions relative to the slit aperture to keep image position variations within tolerable limits. Each detector measures a line position and then uses the line position signal to adjust optical, mechanical, and electronic components in…
Plasma cell for providing VUV filtering in a laser-sustained plasma light source
Granted: March 27, 2018
Patent Number:
9927094
A plasma cell for use in a laser-sustained plasma light source includes a plasma bulb configured to contain a gas suitable for generating a plasma, the plasma bulb being transparent to light from a pump laser, wherein the plasma bulb is transparent to at least a portion of a collectable spectral region of illumination emitted by the plasma. The plasma bulb of the plasma cell is configured to filter short wavelength radiation, such as VUV radiation, emitted by the plasma sustained within…
Method and system for iterative defect classification
Granted: March 20, 2018
Patent Number:
9922269
Defect classification includes acquiring one or more images of a specimen including multiple defects, grouping the defects into groups of defect types based on the attributes of the defects, receiving a signal from a user interface device indicative of a first manual classification of a selected number of defects from the groups, generating a classifier based on the first manual classification and the attributes of the defects, classifying, with the classifier, one or more defects not…
Method and apparatus for non-contact measurement of sheet resistance and shunt resistance of p-n junctions
Granted: March 20, 2018
Patent Number:
9921261
Non-Contact measurement of characteristics of p-n junctions includes illuminating an illumination area of a surface of a p-n junction with light, measuring a first junction photovoltage (JPV) signal from a first area of the p-n junction with a first electrode, measuring a second JPV signal from a second area with a second electrode, measuring a third JPV signal from a third area with a reference electrode, and determining a sheet resistance of the p-n junction top layer with a corrected…
Systems and methods for extended infrared spectroscopic ellipsometry
Granted: March 20, 2018
Patent Number:
9921152
Methods and systems for performing simultaneous spectroscopic measurements of semiconductor structures at ultraviolet, visible, and infrared wavelengths are presented herein. In another aspect, wavelength errors are reduced by orienting the direction of wavelength dispersion on the detector surface perpendicular to the projection of the plane of incidence onto the detector surface. In another aspect, a broad range of infrared wavelengths are detected by a detector that includes multiple…
Simultaneous multi-angle spectroscopy
Granted: March 20, 2018
Patent Number:
9921104
Methods and systems for performing simultaneous spectroscopic measurements of semiconductor structures over a broad range of angles of incidence (AOI), azimuth angles, or both, are presented herein. Spectra including two or more sub-ranges of angles of incidence, azimuth angles, or both, are simultaneously measured over different sensor areas at high throughput. Collected light is linearly dispersed across different photosensitive areas of one or more detectors according to wavelength…
Wafer inspection
Granted: March 13, 2018
Patent Number:
9915622
Systems configured to inspect a wafer are provided. One system includes an illumination subsystem configured to direct pulses of light to an area on a wafer; a scanning subsystem configured to scan the pulses of light across the wafer; a collection subsystem configured to image pulses of light scattered from the area on the wafer to a sensor, wherein the sensor is configured to integrate a number of the pulses of scattered light that is fewer than a number of the pulses of scattered…