Electron source architecture for a scanning electron microscopy system
Granted: August 20, 2019
Patent Number:
10388489
A scanning electron microscopy (SEM) system includes a plurality of electron-optical columns and a plurality of electron beam sources. The electron beam sources include an emitter including one or more emitter tips configured to generate one or more electron beams of a plurality of electron beams. The electron beam sources include a stack of one or more positioners configured to adjust a position of the emitter based on one or more measurements of the electron beam generated by the…
Apparatus and method for chucking warped wafers
Granted: August 13, 2019
Patent Number:
10381256
An apparatus for fixing a wafer, including a chuck having a surface, a plurality of through bores in the chuck extending through the surface of the chuck, a fixed vacuum bellows, and a plurality of floating air bearings, wherein the fixed vacuum bellows and a respective floating air bearing of the plurality of floating air bearings are each individually arranged in separate through bores of the plurality of through bores and elevationally above the surface of the chuck.
Continuous-wave laser-sustained plasma illumination source
Granted: August 13, 2019
Patent Number:
10381216
An optical system for generating broadband light via light-sustained plasma formation includes a chamber, an illumination source, a set of focusing optics, and a set of collection optics. The chamber is configured to contain a buffer material in a first phase and a plasma-forming material in a second phase. The illumination source generates continuous-wave pump illumination. The set of focusing optics focuses the continuous-wave pump illumination through the buffer material to an…
Model-based metrology using images
Granted: August 13, 2019
Patent Number:
10380728
Methods and systems for combining information present in measured images of semiconductor wafers with additional measurements of particular structures within the measured images are presented herein. In one aspect, an image-based signal response metrology (SRM) model is trained based on measured images and corresponding reference measurements of particular structures within each image. The trained, image-based SRM model is then used to calculate values of one or more parameters of…
Identifying process variations during product manufacture
Granted: August 13, 2019
Patent Number:
10379449
Systems and method are presented for identifying process variations during manufacture of products such as semiconductor wafers. At a predetermined stage during manufacture of a first products, images of an area of the first product are obtained using different values of at least one imaging parameter. The images are then analyzed to generate a first contrast signature for said first product indicating variations of contrast with said at least one imaging parameter. At the same…
Systems, methods and metrics for wafer high order shape characterization and wafer classification using wafer dimensional geometry tool
Granted: August 13, 2019
Patent Number:
10379061
Systems and methods for improving results of wafer higher order shape (HOS) characterization and wafer classification are disclosed. The systems and methods in accordance with the present disclosure are based on localized shapes. A wafer map is partitioned into a plurality of measurement sites to improve the completeness of wafer shape representation. Various site based HOS metric values may be calculated for wafer characterization and/or classification purposes, and may also be utilized…
Illumination system, inspection tool with illumination system, and method of operating an illumination system
Granted: August 13, 2019
Patent Number:
10379057
An illumination system, an inspection tool and a method for inspecting an object are disclosed. A configurable area light source is arranged in an illumination optical axis of an illumination beam path, wherein the configurable area light source is configured such that different beam diameters are settable. At least one illumination lens is positioned in the illumination beam path for directing a collimated beam at least onto a field of view on a surface of the object, wherein a value of…
System and method for generating multi-channel tunable illumination from a broadband source
Granted: August 6, 2019
Patent Number:
10371626
A metrology system includes an illumination source to generate an illumination beam, a multi-channel spectral filter, a focusing element to direct illumination from the single optical column to a sample, and at least one detector to capture the illumination collected from the sample. The multi-channel spectral filter includes two or more filtering channels having two or more channel beam paths. The two or more filtering channels filter illumination propagating along the two or more…
Quantifying and reducing total measurement uncertainty
Granted: August 6, 2019
Patent Number:
10372114
A process control technique uses production data from multiple manufacturing tools and multiple inspection or metrology tools. Total measurement uncertainty (TMU) can be calculated on the production data, which can include measurements of one or more devices manufactured using the manufacturing tools. Manufacturing steps can be ranked or otherwise compared by TMU. All production modes and recipes can be continually monitored using production data.
Method for defocus detection
Granted: August 6, 2019
Patent Number:
10372113
Two or more color data can be combined to form a new data source to enhance sensitivity to defocus signal. Defocus detection can be performed on the newly formed data source. In a setup step, a training wafer can be used to select the best color combination, and obtain defocus detection threshold. This can include applying a segment mask, calculating mean intensities of the segment, determining a color combination that optimizes defocus sensitivity, and generating a second segment mask…
Method and system for noise mitigation in a multi-beam scanning electron microscopy system
Granted: July 30, 2019
Patent Number:
10366862
A scanning electron microscopy system is disclosed. The system includes a multi-beam scanning electron microscopy (SEM) sub-system. The SEM sub-system includes a multi-beam electron beam source configured to generate a plurality of electron beams, a sample stage configured to secure a sample, an electron-optical assembly, and a detector assembly configured to detect a plurality of electron signal beams emanating from the surface of the sample to form a plurality of images, each image…
Wafer notch detection
Granted: July 30, 2019
Patent Number:
10366483
Notch detection methods and modules are provided for efficiently estimating a position of a wafer notch. Capturing an image of specified region(s) of the wafer, a principle angle is identified in a transformation, converted into polar coordinates, of the captured image. Then the wafer axes are recovered from the identified principle angle as the dominant orientations of geometric primitives in the captured region. The captured region may be selected to include the center of the wafer…
Feature selection and automated process window monitoring through outlier detection
Granted: July 30, 2019
Patent Number:
10365639
Feature extraction and classification is used for process window monitoring. A classifier, based on combinations of metrics of masked die images and including a set of significant combinations of one or more segment masks, metrics, and wafer images, is capable of detecting a process non-compliance. A process status can be determined using a classifier based on calculated metrics. The classifier may learn from nominal data.
High accuracy of relative defect locations for repeater analysis
Granted: July 30, 2019
Patent Number:
10365232
Methods and systems for transforming positions of defects detected on a wafer are provided. One method includes aligning output of an inspection subsystem for a first frame in a first swath in a first die in a first instance of a multi-die reticle printed on the wafer to the output for corresponding frames, swaths, and dies in other reticle instances printed on the wafer. The method also includes determining different swath coordinate offsets for each of the frames, respectively, in the…
Scatterometry overlay based on reflection peak locations
Granted: July 30, 2019
Patent Number:
10365230
Metrology methods and modules are provided, which comprise measuring intensity spatial distributions and peaks of spots at the pupil plane of a metrology system that correspond to various diffraction orders scattered from target cells and calculating overlay(s) of the target cell(s) from the measured intensity spatial distributions and peaks. For example, intensity peak or distribution of zeroth diffraction orders from four cells, first diffraction orders from two cells as well as…
Multi-location metrology
Granted: July 30, 2019
Patent Number:
10365225
Methods and systems for estimating values of parameters of interest of structures fabricated on a wafer with a signal response metrology (SRM) model trained based on reference measurement data collected from the same wafer are presented herein. In one aspect, the SRM model is an input-output model trained to establish a functional relationship between reference measurements of structures fabricated on the wafer to raw measurement data collected from the same wafer. The raw measurement…
Systems and methods for metrology beam stabilization
Granted: July 30, 2019
Patent Number:
10365211
Methods and systems for measuring a specimen while actively stabilizing an optical measurement beam subject to changes in polarization by a rotating polarizer element are described herein. Movement of a focused measurement beam spot induced by a rotating polarizer element is compensated by actively controlling the position of an optical element in the beam path based on measurements of the focused measurement beam spot. Both feedback and feedforward control schemes may be employed to…
Determining one or more characteristics of a pattern of interest on a specimen
Granted: July 23, 2019
Patent Number:
10359371
Methods and systems for determining characteristic(s) of patterns of interest (POIs) are provided. One system is configured to acquire output of an inspection system generated at the POI instances without detecting defects at the POI instances. The output is then used to generate a selection of the POI instances. The system then acquires output from an output acquisition subsystem for the selected POI instances. The system also determines characteristic(s) of the POI using the output…
Optical measurement of step size and plated metal thickness
Granted: July 23, 2019
Patent Number:
10359613
A method of generating 3D information includes: varying the distance between the sample and an objective lens of the optical microscope at pre-determined steps, capturing an image at each pre-determined step; determining a characteristic value of each pixel in each captured image; determining, for each captured image, the greatest characteristic value across all pixels in the captured image; comparing the greatest characteristic value for each captured image to determine if a surface of…
Beam shaping slit for small spot size transmission small angle X-ray scatterometry
Granted: July 23, 2019
Patent Number:
10359377
Methods and systems for reducing the effect of finite source size on illumination beam spot size for Transmission, Small-Angle X-ray Scatterometry (T-SAXS) measurements are described herein. A beam shaping slit having a slender profile is located in close proximity to the specimen under measurement and does not interfere with wafer stage components over the full range of angles of beam incidence. In one embodiment, four independently actuated beam shaping slits are employed to…
