KLA-Tencor Patent Grants

Bonded wafer metrology

Granted: January 21, 2020
Patent Number: 10540759
Wafer edge profile images are analyzed at locations around a bonded wafer, which may have a top wafer and a carrier wafer. An offset curve is generated based on the wafer edge profile images. Displacement of the top wafer to the carrier wafer is determined based on the offset curve. The wafer edge profile images may be generated at multiple locations around the wafer. The wafer edge profile images may be shadowgram images. A system to determine displacement of the top wafer to the…

Voltage contrast based fault and defect inference in logic chips

Granted: January 21, 2020
Patent Number: 10539612
A voltage contrast imaging defect detection system includes a voltage contrast imaging tool and a controller coupled to the voltage contrast imaging tool. The controller is configured to generate one or more voltage contrast imaging metrics for one or more structures on a sample, determine one or more target areas on the sample based on the one or more voltage contrast imaging metrics, receive a voltage contrast imaging dataset for the one or more target areas on the sample from the…

Block-to-block reticle inspection

Granted: January 21, 2020
Patent Number: 10539512
Block-to-block reticle inspection includes acquiring a swath image of a portion of a reticle with a reticle inspection sub-system, identifying a first occurrence of a block in the swatch image and at least a second occurrence of the block in the swath image substantially similar to the first occurrence of the block and determining at least one of a location, one or more geometrical characteristics of the block and a spatial offset between the first occurrence of the block and the at…

Photocathode designs and methods of generating an electron beam using a photocathode

Granted: January 14, 2020
Patent Number: 10535493
A photocathode can include a body fabricated of a wide bandgap semiconductor material, a metal layer, and an alkali halide photocathode emitter. The body may have a thickness of less than 100 nm and the alkali halide photocathode may have a thickness less than 10 nm. The photocathode can be illuminated with a dual wavelength scheme.

Systems and methods for region-adaptive defect detection

Granted: January 14, 2020
Patent Number: 10535131
A defect detection method includes acquiring a reference image; selecting a target region of the reference image; identifying, based on a matching metric, one or more comparative regions of the reference image corresponding to the target region; acquiring a test image; masking the test image with the target region of the reference image and the one or more comparative regions of the reference image; defining a defect threshold for the target region in the test image based on the one or…

Apparatus and methods for combined brightfield, darkfield, and photothermal inspection

Granted: January 14, 2020
Patent Number: 10533954
Disclosed are methods and apparatus for detecting defects or reviewing defects in a semiconductor sample. The system has a brightfield (BF) module for directing a BF illumination beam onto a sample and detecting an output beam reflected from the sample in response to the BF illumination beam. The system has a modulated optical reflectance (MOR) module for directing a pump and probe beam to the sample and detecting a MOR output beam from the probe spot in response to the pump beam and the…

System and method for wafer inspection with a noise boundary threshold

Granted: January 14, 2020
Patent Number: 10533953
A method includes receiving one or more images of three or more die of a wafer, determining a median intensity value of a set of pixel intensity values acquired from a same location on each of the three or more die, determining a difference intensity value for the set of pixel intensity values by comparing the median intensity value of the set of pixel intensity values to each pixel intensity value, grouping the pixel intensity values into an intensity bin based on the median intensity…

Scanning in angle-resolved reflectometry and algorithmically eliminating diffraction from optical metrology

Granted: January 14, 2020
Patent Number: 10533940
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…

Metrology and control of overlay and edge placement errors

Granted: January 14, 2020
Patent Number: 10533848
An overlay metrology system may include a controller to generate optical tool error adjustments for a hybrid overlay target including optically-resolvable features and device-scale features by measuring a difference between an optical overlay measurement based on the optically-resolvable features and a device-scale overlay measurement based on the device-scale features, generate target-to-device adjustments for the hybrid overlay target based on positions of features within the device…

Compensating for scanning electron microscope beam distortion-induced metrology error using design

Granted: January 7, 2020
Patent Number: 10529534
Methods and systems for quantifying and correcting for non-uniformities in images used for metrology operations are disclosed. A metrology area image of a wafer and a design clip may be used. The metrology area image may be a scanning electron microscope image. The design clip may be the design clip of the wafer or a synthesized design clip. Tool distortions, including electron beam distortions, can be quantified and corrected. The design clip can be applied to the metrology area image…

Multi-layer overlay metrology target and complimentary overlay metrology measurement systems

Granted: January 7, 2020
Patent Number: 10527954
A system for measuring overlay from a multi-layer overlay target for use in imaging based metrology is disclosed. The system is configured for measuring overlay from a multi-layer overly target that includes three or more target structures, wherein a first target structure is disposed in a first process layer, a second target structure is disposed in a second process layer, and at least a third target structure is disposed in at least a third process layer. The system includes an…

Fault discrimination and calibration of scatterometry overlay targets

Granted: January 7, 2020
Patent Number: 10527952
Scatterometry overlay targets and measurement methods are provided, which are configured to detect and eliminate process-related errors and illumination-related errors from overlay measurements of the targets. Targets comprise at least three cells associated with a measurement direction, wherein at least two of the cells comprise periodic structures at different target layers, having a same pitch and opposite offsets between the two cells, and at least an additional cell comprises a…

Compound imaging metrology targets

Granted: January 7, 2020
Patent Number: 10527951
Imaging metrology targets and methods are provided, which combine one-dimensional (1D) elements designed to provide 1D imaging metrology signals along at least two measurement directions and two-dimensional (2D) elements designed to provide at least one 2D imaging metrology overlay signal. The target area of the 1D elements may enclose the 2D elements or the target areas of the 1D and 2D elements may be partially or fully congruent. The compound targets are small, possibly multilayered,…

Off-axis reflective afocal optical relay

Granted: January 7, 2020
Patent Number: 10527830
An optical relay system includes four or more reflective optical elements oriented in a tilted configuration. Each of the four or more reflective optical elements is tilted about one of four or more tilt axes. Further, the four or more tilt axes are oriented to correct for aberrations induced by the tilted configuration.

Haze mask system for haze suppression

Granted: December 31, 2019
Patent Number: 10522426
This system and method minimize an effect of haze to signal-to-noise ratio and compensate for haze on the haze map. A first mask with a first aperture is disposed along the path of the light beam between a light source and a collector. A first actuator moves the first mask along a tangential direction. A second mask with a second aperture is disposed along the path of the light beam between the first mask and the collector. A second actuator moves the second mask along a radial direction…

Multi-step image alignment method for large offset die-die inspection

Granted: December 31, 2019
Patent Number: 10522376
A die-die inspection image can be aligned using a method or system configured to receive a reference image and a test image, determine a global offset and rotation angle from local sections on the reference image and test image, and perform a rough alignment de-skew of the test image prior to performing a fine alignment.

Broadband light source including transparent portion with high hydroxide content

Granted: December 31, 2019
Patent Number: 10522340
A laser-sustained plasma light source includes a plasma lamp configured to contain a volume of gas and receive illumination from a pump laser in order to generate a plasma. The plasma lamp includes one or more transparent portions transparent to illumination from the pump laser and at least a portion of the broadband radiation emitted by the plasma. The one or more transparent portions are formed from a transparent material having elevated hydroxide content above 700 ppm.

Topographic phase control for overlay measurement

Granted: December 31, 2019
Patent Number: 10520832
Metrology tools and methods are provided, which estimate the effect of topographic phases corresponding to different diffraction orders, which result from light scattering on periodic targets, and adjust the measurement conditions to improve measurement accuracy. In imaging, overlay error magnification may be reduced by choosing appropriate measurement conditions based on analysis of contrast function behavior, changing illumination conditions (reducing spectrum width and illumination…

System and method for separation of pump light and collected light in a laser pumped light source

Granted: December 31, 2019
Patent Number: 10520741
A system for separating plasma pumping light and collected broadband light includes a pump source configured to generate pumping illumination including at least a first wavelength, a gas containment element for containing a volume of gas, a collector configured to focus the pumping illumination from the pumping source into the volume of gas to generate a plasma within the volume of gas, wherein the plasma emits broadband radiation including at least a second wavelength and an…

Resistivity probe having movable needle bodies

Granted: December 24, 2019
Patent Number: 10514391
Resistivity probes can be used to test integrated circuits. In one example, a resistivity probe has a substrate with multiple vias and multiple metal pins. Each of the metal pins is disposed in one of the vias. The metal pins extend out of the substrate. Interconnects provide an electrical connection to the metal pins. In another example, a resistivity probe has a substrate with a top surface and multiple elements extending from the substrate. Each of the elements curves from the…