Adaptive numerical aperture control method and system
Granted: June 9, 2020
Patent Number:
10678226
Systems and methods for providing efficient modeling and measurement of critical dimensions and/or overlay registrations of wafers are disclosed. Efficiency is improved in both spectral dimension and temporal dimension. In the spectral dimension, efficiency can be improved by allowing different numerical aperture (NA) models to be used for different wavelengths in electromagnetic calculations, effectively providing a balance between computation speed and accuracy. In the temporal…
Detecting die repeating programmed defects located in backgrounds with non-repeating features
Granted: June 9, 2020
Patent Number:
10677742
Systems and methods for detecting programmed defects on a water during inspection of the wafer are provided. One method includes selecting a mode of an inspection subsystem for detecting programmed defects on a wafer that generates output for the wafer having the lowest non-defect signal and at least a minimum signal for the programmed defects. The method also includes selecting a training care area that is mutually exclusive of care area(s) used for detecting the programmed defects…
Localized telecentricity and focus optimization for overlay metrology
Granted: June 9, 2020
Patent Number:
10677588
An overlay metrology tool providing site-by-site alignment includes a controller coupled to a telecentric imaging system. The controller may receive two or more alignment images of an overlay target on a sample captured at two or more focal positions by the imaging system, generate alignment data indicative of an alignment of the overlay target within the imaging system based on the alignment images, set the alignment images as measurement images when the alignment of the overlay target…
Phase revealing optical and X-ray semiconductor metrology
Granted: June 9, 2020
Patent Number:
10677586
The embodiments disclosed herein can enable a target on a semiconductor wafer to be reconstructed and/or imaged. A surface of a target on a semiconductor wafer is measured using a wafer metrology tool. A voxel map of the surface is fixed to match geometry measurements and using scattering density of expected materials. Uniform scaling of the scattering density of all fixed surface voxels can occur.
Using deep learning based defect detection and classification schemes for pixel level image quantification
Granted: June 2, 2020
Patent Number:
10672588
A heat map of probable defects in an image can be represented as a matrix of defect probability index corresponding to each pixel. The image may be generated from data received from a detector of a scanning electron microscope or other inspection tools. A number of pixels in the image that exceed a corresponding threshold in the matrix can be quantified.
Systems and methods for defect material classification
Granted: June 2, 2020
Patent Number:
10670537
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…
Mode selection for inspection
Granted: June 2, 2020
Patent Number:
10670536
Methods and systems for selecting a mode for inspection of a specimen are provided. One method includes determining how separable defects of interest (DOIs) and nuisances detected on a specimen are in one or more modes of an inspection subsystem. The separability of the modes for the Dais and nuisances is used to select a subset of the modes for inspection of other specimens of the same type. Other characteristics of the performance of the modes may be used in combination with the…
Automated pattern fidelity measurement plan generation
Granted: June 2, 2020
Patent Number:
10670535
Methods and systems for determining parameter(s) of a metrology process to be performed on a specimen are provided. One system includes one or more computer subsystems configured for automatically generating regions of interest (ROIs) to be measured during a metrology process performed for the specimen with the measurement subsystem based on a design for the specimen. The computer subsystem(s) are also configured for automatically determining parameter(s) of measurement(s) performed in…
Systems and methods for optimizing focus for imaging-based overlay metrology
Granted: May 26, 2020
Patent Number:
10663281
Methods and systems for focusing and measuring by mean of an interferometer device, having an optical coherence tomography (OCT) focusing system, by separately directing an overlapped measurement and reference wavefront towards a focus sensor and towards an imaging sensor; where a predefined focusing illumination spectrum of the overlapped wavefront is directed towards the focus sensor, and where a predefined measurement illumination spectrum of the overlapped wavefront is directed…
Measuring thin films on grating and bandgap on grating
Granted: May 26, 2020
Patent Number:
10663286
Methods and systems disclosed herein can measure thin film stacks, such as film on grating and bandgap on grating in semiconductors. For example, the thin film stack may be a 1D film stack, a 2D film on grating, or a 3D film on grating. One or more effective medium dispersion models are created for the film stack. Each effective medium dispersion model can substitute for one or more layers. A thickness of one or more layers can be determined using the effective medium dispersion based…
Dynamic determination of metal film thickness from sheet resistance and TCR value
Granted: May 26, 2020
Patent Number:
10663279
Metal film thickness can be determined using the sheet resistance, resistivity, and temperature coefficient of resistivity for the metal film. Variation in film thickness measurements caused by resistivity can be reduced or eliminated. A probe head may be used for some of the measurements of the metal film. The probe head can include a temperature sensor used during sheet resistance measurements. A wafer on a chuck is heated, such as using the chuck or the probe head, for the…
Wafer defect inspection and review systems
Granted: May 19, 2020
Patent Number:
10656098
Imaging objectives and inspection systems equipped with such imaging objectives are disclosed. The imaging objective may include a front objective configured to produce a diffraction limited intermediate image. The imaging objective may also include a relay configured to receive the intermediate image produced by the front objective. The relay may include three spherical mirrors positioned to deliver a projection of the intermediate image to a fixed image plane.
Automatic defect classification without sampling and feature selection
Granted: May 12, 2020
Patent Number:
10650508
Systems and methods for defection classification in a semiconductor process are provided. The system includes a communication line configured to receive a defect image of a wafer from the semiconductor process and a deep-architecture neural network in electronic communication with the communication line. The neural network has a first convolution layer of neurons configured to convolve pixels from the defect image with a filter to generate a first feature map. The neural network also…
Methods and systems for creating or performing a dynamic sampling scheme for a process during which measurements are performed on wafers
Granted: May 12, 2020
Patent Number:
10649447
Various methods and systems for creating or performing a dynamic sampling scheme for a process during which measurements are performed on wafers are provided. One method for creating a dynamic sampling scheme for a process during which measurements are performed on wafers includes performing the measurements on all of the wafers in at least one lot at all measurement spots on the wafers. The method also includes determining an optimal sampling scheme, an enhanced sampling scheme, a…
Repeater defect detection
Granted: May 12, 2020
Patent Number:
10648925
Defects from a hot scan can be saved, such as on persistent storage, random access memory, or a split database. The persistent storage can be patch-based virtual inspector virtual analyzer (VIVA) or local storage. Repeater defect detection jobs can determined and the wafer can be inspected based on the repeater defect detection jobs. Repeater defects can be analyzed and corresponding defect records to the repeater defects can be read from the persistent storage. These results may be…
Generating high resolution images from low resolution images for semiconductor applications
Granted: May 12, 2020
Patent Number:
10648924
Methods and systems for generating a high resolution image for a specimen from one or more low resolution images of the specimen are provided. One system includes one or more computer subsystems configured for acquiring one or more low resolution images of a specimen. The system also includes one or more components executed by the one or more computer subsystems. The one or more components include a model that includes one or more first layers configured for generating a representation…
Optical metrology with small illumination spot size
Granted: May 12, 2020
Patent Number:
10648796
Methods and systems are presented to reduce the illumination spot size projected onto a measurement target and associated spillover onto area surrounding a measurement target. In one aspect, a spatial light modulator (SLM) is located in the illumination path between the illumination light source and the measurement sample. The SLM is configured to modulate amplitude, phase, or both, across the path of the illumination light to reduce wavefront errors. In some embodiments, the desired…
Library expansion system, method, and computer program product for metrology
Granted: May 12, 2020
Patent Number:
10648793
A library expansion system, method, and computer program product for metrology are provided. In use, processing within a first multi-dimensional library is performed by a metrology system. During the processing within the first multi-dimensional library, a second multi-dimensional library is identified. The processing is then transitioned to the second multi-dimensional library. Further, processing within the second multi-dimensional library is performed by the metrology system.
Method and system for charged particle microscopy with improved image beam stabilization and interrogation
Granted: May 5, 2020
Patent Number:
10643819
A scanning electron microscopy system with improved image beam stability is disclosed. The system includes an electron beam source configured to generate an electron beam and a set of electron-optical elements to direct at least a portion of the electron beam onto a portion of the sample. The system includes an emittance analyzer assembly. The system includes a splitter element configured to direct at least a portion secondary electrons and/or backscattered electrons emitted by a surface…
Phase contrast monitoring for extreme ultra-violet (EUV) masks defect inspection
Granted: April 28, 2020
Patent Number:
10634623
Disclosed are methods and apparatus for inspecting an extreme ultraviolet (EUV) reticle using an optical inspection tool. An inspection tool having a pupil filter positioned at an imaging pupil is used to obtain a test image or signal from an output beam that is reflected and scattered from a test portion of an EUV test reticle. The pupil filter is configured to provide phase contrast in the output beam. A reference image or signal is obtained for a reference reticle portion that is…
