High damage threshold frequency conversion system
Granted: September 5, 2017
Patent Number:
9753352
The present invention includes a fundamental laser light source configured to generate fundamental wavelength laser light, a first nonlinear optical crystal configured to generate first alternate wavelength light, a second nonlinear optical crystal configured to generate second alternate wavelength light, a set of Brewster angle wavefront processing optics configured to condition the first and second alternate wavelengths of light, and a harmonic separator configured to receive the first…
Variable image field curvature for object inspection
Granted: September 5, 2017
Patent Number:
9752992
Field curvature of an optical system is modified based on topography of the surface of a wafer such that an image of each of the segments of the surface is in focus across the segment. The wafer may be non-planar. The optical system may be a multi-element lens system connected to a controller that modifies the field curvature by changing position of the lens elements. The wafer may be held by a chuck, such as an edge grip chuck. Multiple optical systems may be arranged across a dimension…
183NM laser and inspection system
Granted: August 29, 2017
Patent Number:
9748729
A laser assembly for generating laser output light at an output wavelength of approximately 183 nm includes a fundamental laser, an optical parametric system (OPS), a fifth harmonic generator, and a frequency mixing module. The fundamental laser generates fundamental light at a fundamental frequency. The OPS generates a down-converted signal at a down-converted frequency. The fifth harmonic generator generates a fifth harmonic of the fundamental light. The frequency mixing module mixes…
Anti-reflection layer for back-illuminated sensor
Granted: August 29, 2017
Patent Number:
9748294
An image sensor for short-wavelength light includes a semiconductor membrane, circuit elements formed on one surface of the semiconductor membrane, and a pure boron layer on the other surface of the semiconductor membrane. An anti-reflection or protective layer is formed on top of the pure boron layer. This image sensor has high efficiency and good stability even under continuous use at high flux for multiple years. The image sensor may be fabricated using CCD (charge coupled device) or…
Method and system for improving wafer surface inspection sensitivity
Granted: August 29, 2017
Patent Number:
9747670
Improvement of wafer surface inspection sensitivity includes acquiring a first inspection image from the surface of the wafer, generating a reference image by applying a thresholding function to the first image in order to isolate a speckle signal component of the first image induced by wafer surface roughness, acquiring one or more measurement inspection images from the surface of the wafer, and generating a difference image by subtracting the generated one or more reference images from…
Systems and methods for enhancing inspection sensitivity of an inspection tool
Granted: August 29, 2017
Patent Number:
9747520
Systems and methods for enhancing inspection sensitivity to detect defects in wafers using an inspection tool are disclosed. A plurality of light emitting diodes illuminate at least a portion of a wafer and capture a set of grayscale images. A residual signal is determined in each image of the grayscale image set and the residual signal is subtracted from each image of the grayscale image set. Defects are identified based on the subtracted grayscale image set. Models of the inspection…
Automatic calibration sample selection for die-to-database photomask inspection
Granted: August 29, 2017
Patent Number:
9747518
A method for selecting samples of reticle design data patterns in order to calibrate the parameters based on which the reference image used in a die-to-database reticle inspection method is rendered, the method comprising the steps of applying local binary pattern (LBP) analysis to a plurality of samples to obtain a p-dimensional vector output for each of the plurality of samples, clustering the q-D data points to M groups, selecting one sample from each clustered group, calculating…
Apparatus and method for accurate measurement and mapping of forward and reverse-bias current-voltage characteristics of large area lateral p-n junctions
Granted: August 29, 2017
Patent Number:
9746514
Methods and apparatus for providing measurements in p-n junctions and taking into account the lateral current for improved accuracy are disclosed. The lateral current may be controlled, allowing the spreading of the current to be reduced or substantially eliminated. Alternatively or additionally, the lateral current may be measured, allowing a more accurate normal current to be calculated by compensating for the measured spreading. In addition, the techniques utilized for controlling the…
Method, computer system and apparatus for recipe generation for automated inspection of semiconductor devices
Granted: August 22, 2017
Patent Number:
9739720
A method, a computer system and an apparatus are disclosed for inspection recipe generation for the automated inspection of semiconductor devices. In order to generate the inspection recipe a reference data set is used. Automatic inspection is carried out with an initial recipe on images of dies of the reference data set (reference wafermap). The detected inspection results from the automatic inspection are classified and the classified inspection results are compared with an expert…
Scatterometry overlay metrology targets and methods
Granted: August 22, 2017
Patent Number:
9740108
Scatterometry overlay (SCOL) targets as well as design, production and measurement methods thereof are provided. The SCOL targets have several periodic structures at different measurement directions which share some of their structural target elements or parts thereof. An array of common elements may have symmetry directions which are parallel to the measurement directions and thus enable compacting the targets or alternatively increasing the area use efficiency of the targets. Various…
Measurement systems having linked field and pupil signal detection
Granted: August 22, 2017
Patent Number:
9739719
Methods and systems for simultaneous detection and linked processing of field signals and pupil signals are presented herein. In one aspect, estimates of one or more structural or process parameter values are based on field measurement signals, pupil measurement signals, or both. In addition, the quality of the measurements of the one or more structural or process parameter values is characterized based on the field measurement signals, pupil measurement signals, or both. In some…
Symmetric target design in scatterometry overlay metrology
Granted: August 22, 2017
Patent Number:
9739702
Metrology methods, systems and targets are provided, which implement a side by side paradigm. Adjacent cells with periodic structures are used to extract the overlay error, e.g., by introducing controllable phase shifts or image shifts which enable algorithmic computation of the overlay. The periodic structures are designed to exhibit a rotational symmetry to support the computation and reduce errors.
Sub 200nm laser pumped homonuclear excimer lasers
Granted: August 15, 2017
Patent Number:
9735534
Disclosed are methods and apparatus for generating a sub-200 nm continuous wave (cw) laser. A laser apparatus includes a chamber for receiving at least a rare gas or rare gas mixtures and a pump laser source for generating at least one cw pump laser focused in the chamber for generating at least one laser-sustained plasma in the chamber. The laser apparatus further includes a system for forming an optical cavity in which the at least one laser-sustained plasma serves as an excitation…
Method and system for adaptively scanning a sample during electron beam inspection
Granted: August 15, 2017
Patent Number:
9734987
A system for adaptive electron beam scanning may include an inspection sub-system configured to scan an electron beam across the surface of a sample. The inspection sub-system may include an electron beam source, a sample stage, a set of electron-optic elements, a detector assembly and a controller communicatively coupled to one or more portions of the inspection sub-system. The controller may assess one or more characteristics of one or more portions of an area of the sample for…
Automated inline inspection and metrology using shadow-gram images
Granted: August 15, 2017
Patent Number:
9734568
Shadow-grams are used for edge inspection and metrology of a stacked wafer. The system includes a light source that directs collimated light at an edge of the stacked wafer, a detector opposite the light source, and a controller connected to the detector. The stacked wafer can rotate with respect to the light source. The controller analyzes a shadow-gram image of the edge of the stacked wafer. Measurements of a silhouette of the stacked wafer in the shadow-gram image are compared to…
System and method for enhanced defect detection with a digital matched filter
Granted: August 15, 2017
Patent Number:
9734422
Enhanced defect detection of a sample includes acquiring two or more inspection images from a sample from two or more locations of the sample for a first optical mode. The defect detection also generates an aggregated defect profile based on the two or more inspection images from the two or more locations for the first optical mode for a selected defect type and calculating one or more noise correlation characteristics of the two or more inspection images acquired from the two or more…
Method and apparatus for database-assisted requalification reticle inspection
Granted: August 15, 2017
Patent Number:
9733640
A method embodiment includes providing a reticle design data that specify a plurality of printable features that are formed on the wafer using the reticle and a plurality of nonprintable features that are not formed on the wafer using such reticle, wherein the reticle design data is usable to fabricate the reticle. A reduced design database is generated from the reticle design data and this reduced design database includes a description or map of the nonprintable features of the reticle,…
Model for accurate photoresist profile prediction
Granted: August 15, 2017
Patent Number:
9733576
A photoresist modelling system includes a mathematical model for a photolithography process. The mathematical model may be executable using a computer processor. The mathematical model may be used to model a photoresist as formed on a semiconductor wafer surface. A blocked polymer concentration gradient equation may be implemented into the mathematical model. The blocked polymer concentration gradient equation may describe an initial concentration gradient of a blocked polymer in the…
Apparatus and methods for finding a best aperture and mode to enhance defect detection
Granted: August 8, 2017
Patent Number:
9726617
Disclosed are methods and apparatus for optimizing a mode of an inspection tool. A first image or signal for each of a plurality of first apertures of the inspection tool is obtained, and each first image or signal pertains to a defect area. For each of a plurality of combinations of the first apertures and their first images or signals, a composite image or signal is obtained. Each composite image or signal is analyzed to determine an optimum one of the combinations of the first…
Aperture alignment in scatterometry metrology systems
Granted: August 8, 2017
Patent Number:
9726984
Methods and algorithms are provided, as well as new metrics for misalignment of apertures with respect to the optical axis of a metrology system. The methods comprise aligning aperture(s) to an optical axis of a scatterometry metrology tool using correction term(s) derived by minimizing an overlay variation measure calculated with respect to overlay measurements of a periodic structure. These methods result in highly sensitive misalignment metrics, which may be used in calibration stages…
