KLA-Tencor Patent Grants

Near field metrology

Granted: April 16, 2019
Patent Number: 10261014
Metrology systems and methods are provided herein, which comprise an optical element that is positioned between an objective lens of the system and a target. The optical element is arranged to enhance evanescent modes of radiation reflected by the target. Various configurations are disclosed: the optical element may comprise a solid immersion lens, a combination of MoirĂ©-elements and solid immersion optics, dielectric-metal-dielectric stacks of different designs, and resonating elements…

System and method for laser-sustained plasma illumination

Granted: April 9, 2019
Patent Number: 10257918
An illumination pump source is disclosed. The illumination pump source includes a set of power sources configured to generate a set of laser beams, with at least some of the set of laser beams configured to include illumination having different wavelengths. The illumination pump source also includes an optical fiber. The illumination pump source also includes one or more optical elements, the one or more optical elements configured to couple the illumination from at least some of the…

Model optimization approach based on spectral sensitivity

Granted: April 9, 2019
Patent Number: 10255385
Model optimization approaches based on spectral sensitivity is described. For example, a method includes determining a first model of a structure. The first model is based on a first set of parameters. A set of spectral sensitivity variations data is determined for the structure. Spectral sensitivity is determined by derivatives of the spectra with respect to the first set of parameters. The first model of the structure is modified to provide a second model of the structure based on the…

Reverse decoration for defect detection amplification

Granted: April 2, 2019
Patent Number: 10249546
Reverse decoration can be used to detect defects in a device. The wafer can include NAND stacks or other devices. The defect can be a channel bridge, a void, or other types of defects. Reverse decoration can preserve a defect and/or can improve defect detection. A portion of a layer may be removed from a device. A layer also may be added to the device, such as on the defect, and some of the layer may be removed.

Overlay and semiconductor process control using a wafer geometry metric

Granted: April 2, 2019
Patent Number: 10249523
The present invention may include acquiring a wafer shape value at a plurality of points of a wafer surface at a first and second process level, generating a wafer shape change value at each of the points, generating a set of slope of shape change values at each of the points, calculating a set of process tool correctables utilizing the generated set of slope of shape change values, generating a set of slope shape change residuals (SSCRs) by calculating a slope of shape change residual…

System and method for electrodeless plasma ignition in laser-sustained plasma light source

Granted: March 26, 2019
Patent Number: 10244613
An illumination source for igniting and sustaining a plasma in a plasma lamp of a laser-sustained plasma (LSP) broadband source includes one or more ignition lasers configured to ignite the plasma within a gas contained within the plasma lamp. The illumination sources also include one or more sustaining lasers configured to sustain the plasma. The illumination sources include a delivery optical fiber, one or more optical elements configured to selectively optically couple an output of…

Reduced Coulomb interactions in a multi-beam column

Granted: March 26, 2019
Patent Number: 10242839
Performance of a multi-electron-beam system can be improved by reducing Coulomb effects in the illumination path of a multi-beam inspection system. A beam-limiting aperture with multiple holes can be positioned between an electron beam source and a multi-lens array, such as in a field-free region. The beam-limiting aperture is configured to reduce Coulomb interactions between the electron beam source and the multi-lens array. An electron beam system with the beam-limiting aperture can be…

Method, system, and user interface for metrology target characterization

Granted: March 26, 2019
Patent Number: 10242290
Methods and systems are provided, which identify specified metrology target abnormalities using selected metrics and classify the identified target abnormalities geometrically to link them to corresponding sources of error. Identification may be carried out by deriving target signals such as kernels from specified regions of interest (ROIs) from corresponding targets on a wafer, calculating the metrics from the target signals using respective functions and analyzing the metrics to…

System and method for reducing radiation-induced false counts in an inspection system

Granted: March 26, 2019
Patent Number: 10241217
An inspection system with radiation-induced false count mitigation includes a radiation count controller coupled to one or more radiation sensors positioned proximate to an illumination sensor oriented to detect illumination from a sample. The radiation count controller may identify a set of radiation detection events based on radiation signals received from the radiation sensors during operation of the illumination sensor. The inspection system may further include an inspection…

System and method for measuring substrate and film thickness distribution

Granted: March 19, 2019
Patent Number: 10236222
The system includes a dual interferometer sub-system configured to measure flatness across a substrate. The system includes a mass sensor configured to measure the mass of the substrate. The system includes a controller communicatively coupled to the dual interferometer sub-system and the mass sensor. The controller includes one or more processors. The one or more processors are configured to execute a set of program instructions stored in memory, the set of program instructions…

Systems and methods for defect material classification

Granted: March 19, 2019
Patent Number: 10234402
A inspection system includes an illumination source to generate an illumination beam, focusing elements to direct the illumination beam to a sample, a detector, collection elements configured to direct radiation emanating from the sample to the detector, a detection mode control device to image the sample in two or more detection modes such that the detector generates two or more collection signals based on the two or more detection modes, and a controller. Radiation emanating from the…

Reflection symmetric scatterometry overlay targets and methods

Granted: March 19, 2019
Patent Number: 10234280
A method for target measurement is provided which comprises designing a reflection-symmetric target and measuring overlays of the target along at least one reflection symmetry direction of the target. Also, a tool calibration method comprising calibrating a scatterometry measurement tool with respect to a reflection symmetry of a reflection symmetric target. Further provided are methods of measuring scatterometry overlay using first order and zeroth order scatterometry measurements of a…

Method and system for spectroscopic beam profile metrology including a detection of collected light according to wavelength along a third dimension of a hyperspectral detector

Granted: March 19, 2019
Patent Number: 10234271
A spectroscopic beam profile metrology system simultaneously detects measurement signals over a large wavelength range and a large range of angles of incidence (AOI). In one aspect, a multiple wavelength illumination beam is reshaped to a narrow line shaped beam of light before projection onto a specimen by a high numerical aperture objective. After interaction with the specimen, the collected light is passes through a wavelength dispersive element that projects the range of AOIs along…

Methods and apparatus for polarized wafer inspection

Granted: March 12, 2019
Patent Number: 10228331
This system comprises an illumination optics subsystem for generating and directing an incident beam towards a defect on a surface of a wafer. The illumination optics subsystem includes a light source for generating the incident beam and one or more polarization components for adjusting a ratio and/or a phase difference for the incident beam's electric field components. The system includes a collection optics subsystem for collecting scattered light from the defect and/or surface in…

Method and system for aberration correction in an electron beam system

Granted: March 5, 2019
Patent Number: 10224177
A scanning electron microscopy system is disclosed. The system includes an electron beam source configured to generate a primary electron beam. The system includes a sample stage configured to secure a sample. The system includes a set of electron-optical elements configured to direct at least a portion of the primary electron beam onto a portion of the sample. The set of electron-optical elements includes an upper deflector assembly and a lower deflector assembly. The upper deflector…

Based device risk assessment

Granted: March 5, 2019
Patent Number: 10223492
The process for design based assessment includes the following steps. First, the process defines multiple patterns of interest (POIs) utilizing design data of a device and then generates a design based classification database. Further, the process receives one or more inspection results. Then, the process compares the inspection results to each of the plurality of POIs in order to identify occurrences of the POIs in the inspection results. In turn, the process determines yield impact of…

Method and system for measuring radiation and temperature exposure of wafers along a fabrication process line

Granted: February 26, 2019
Patent Number: 10215626
A measurement wafer device for measuring radiation intensity and temperature includes a wafer assembly including one or more cavities. The measurement wafer device further includes a detector assembly. The detector assembly includes one or more light sensors. The detector assembly is further configured to perform a direct or indirect measurement of the intensity of ultraviolet light incident on a surface of the wafer assembly.

Process-sensitive metrology systems and methods

Granted: February 26, 2019
Patent Number: 10216096
A lithography system includes an illumination source and a set of projection optics. The illumination source directs a beam of illumination from an off-axis illumination pole to a pattern mask. The pattern mask includes a set of pattern elements to generate a set of diffracted beams including illumination from the illumination pole. At least two diffracted beams of the set of diffracted beams received by the set of projection optics are asymmetrically distributed in a pupil plane of the…

Infrared spectroscopic reflectometer for measurement of high aspect ratio structures

Granted: February 26, 2019
Patent Number: 10215693
Methods and systems for performing spectroscopic reflectometry measurements of semiconductor structures at infrared wavelengths are presented herein. In some embodiments measurement wavelengths spanning a range from 750 nanometers to 2,600 nanometers, or greater, are employed. In one aspect, reflectometry measurements are performed at oblique angles to reduce the influence of backside reflections on measurement results. In another aspect, a broad range of infrared wavelengths are…

Optical metrology tool equipped with modulated illumination sources

Granted: February 26, 2019
Patent Number: 10215688
The system includes a modulatable illumination source configured to illuminate a surface of a sample disposed on a sample stage, a detector configured to detect illumination emanating from a surface of the sample, illumination optics configured to direct illumination from the modulatable illumination source to the surface of the sample, collection optics configured to direct illumination from the surface of the sample to the detector, and a modulation control system communicatively…