Continuous-wave laser-sustained plasma illumination source
Granted: December 25, 2018
Patent Number:
10163620
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…
Optical measurement of opening dimensions in a wafer
Granted: December 18, 2018
Patent Number:
10157457
A method of generating 3D information of a sample using an optical microscope 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 a first captured image that is focused on a first surface of the sample based on the characteristic value of each pixel in each captured image, and…
Oven enclosure for optical components with integrated purge gas pre-heater
Granted: December 11, 2018
Patent Number:
10153215
A cartridge in an oven enclosure includes a pre-heating feature for an incoming purge gas before the purge gas enters the space around an optical component, such as a nonlinear optical crystal, in an oven cell. The incoming purge gas can be pre-heated as it travels along a gas pathway around a cartridge. The cartridge can include a heater. The oven enclosure can have two windows positioned such that a laser beam can enter through one of the windows, pass through the optical component,…
System, method and computer program product for combining raw data from multiple metrology tools
Granted: December 11, 2018
Patent Number:
10152678
A system, method and computer program product are provided for combining raw data from multiple metrology tools. Reference values are obtained for at least one parameter of a training component. Signals are collected for the at least one parameter of the training component, utilizing a first metrology tool and a different second metrology tool. Further, at least a portion the signals are transformed into a set of signals, and for each of the at least one parameter of the training…
Signal response metrology for image based overlay measurements
Granted: December 11, 2018
Patent Number:
10152654
Methods and systems for creating an image-based measurement model based only on measured, image-based training data are presented. The trained, image-based measurement model is then used to calculate values of one or more parameters of interest directly from measured image data collected from other wafers. The image-based measurement models receive image data directly as input and provide values of parameters of interest as output. In some embodiments, the image-based measurement model…
Signal response metrology based on measurements of proxy structures
Granted: December 11, 2018
Patent Number:
10151986
Methods and systems for estimating values of parameters of interest of actual device structures based on optical measurements of nearby metrology targets are presented herein. High throughput, inline metrology techniques are employed to measure metrology targets located near actual device structures. Measurement data collected from the metrology targets is provided to a trained signal response metrology (SRM) model. The trained SRM model estimates the value of one or more parameters of…
Inspection for specimens with extensive die to die process variation
Granted: December 11, 2018
Patent Number:
10151706
Methods and systems for detecting defects on a specimen are provided. One method includes identifying first and second portions of dies on a specimen as edge dies and center dies, respectively. The method also includes determining first and second inspection methods for the first and second portions, respectively. Parameter(s) of comparisons performed in the first and second inspection methods are different. The method further includes detecting defects in at least one of the edge dies…
Spectroscopy with tailored spectral sampling
Granted: December 11, 2018
Patent Number:
10151631
A spectrometer for tailored spectral sampling includes a dispersive element for spatially dispersing a spectrum of a light beam, a detector including a plurality of pixels distributed along a sampling direction, and a spectrum reshaping element including at least one of a reflective surface or a transmissive surface for reshaping the spatially-dispersed spectrum of the light beam from the dispersive element along the sampling direction to provide a selected distribution of the spectrum…
Periodic patterns and technique to control misalignment between two layers
Granted: December 11, 2018
Patent Number:
10151584
A method and system to measure misalignment error between two overlying or interlaced periodic structures are proposed. The overlying or interlaced periodic structures are illuminated by incident radiation, and the diffracted radiation of the incident radiation by the overlying or interlaced periodic structures are detected to provide an output signal. The misalignment between the overlying or interlaced periodic structures may then be determined from the output signal.
System and method for LADAR-based optic alignment and characterization
Granted: December 4, 2018
Patent Number:
10145944
An optical alignment system includes a LADAR sub-system including: a laser source and a probe configured to deliver probe illumination from the laser source to a first optical surface of the optical system and an additional optical surface of the optical system. The probe is further configured to receive a first measurement signal from the first optical surface and an additional measurement signal from the additional optical surface of the optical system. The system also includes a…
Measurement of semiconductor structures with capillary condensation
Granted: December 4, 2018
Patent Number:
10145674
Methods and systems for performing optical measurements of geometric structures filled by a capillary condensation process are presented herein. Measurements are performed while the structures under measurement are treated with a flow of purge gas that includes a controlled amount of fill material. A portion of the fill material condenses onto the structures under measurement and fills openings in the structural features, spaces between structural features, small volumes such as notches,…
Measurement of overlay and edge placement errors with an electron beam column array
Granted: November 27, 2018
Patent Number:
10141156
Methods and systems for performing measurements of multiple die with an array of electron beam columns are presented herein. The wafer is scanned in a direction parallel to the die rows disposed on the wafer. The electron beam measurement columns are spatially separated in a column alignment direction. The wafer is scanned in a direction that is oriented at an oblique angle with respect to the column alignment direction such that each electron beam column measures the same row of die…
Electron beam emitters with ruthenium coating
Granted: November 27, 2018
Patent Number:
10141155
An emitter with a protective cap layer on an exterior surface of the emitter is disclosed. The emitter can have a diameter of 100 nm or less. The protective cap layer includes ruthenium. Ruthenium is resistant to oxidation and carbon growth. The protective cap layer also can have relatively low sputter yields to withstand erosion by ions. The emitter may be part of a system with an electron beam source. An electric field can be applied to the emitter and an electron beam can be generated…
Polygon-based geometry classification for semiconductor mask inspection
Granted: November 27, 2018
Patent Number:
10140698
Disclosed are methods and apparatus for providing feature classification for inspection of a photolithographic mask. A design database for fabrication of a mask includes polygons that are each defined by a set of vertices. Any of the polygons that abut each other are grouped together. Any grouped polygons are healed so as to eliminate interior edges of each set of grouped polygons to obtain a polygon corresponding to a covering region of such set of grouped polygons. Geometric…
Compound objectives for imaging and scatterometry overlay
Granted: November 27, 2018
Patent Number:
10139528
Objective lenses and corresponding optical systems and metrology tools, as well as methods are provided. Objective lenses comprise a central region conforming to specified imaging requirements and a peripheral region conforming to specified scatterometry requirements. The optical systems may comprise common-path optical elements configured to handle both imaging and scatterometry signals received through the objective lens. Using a single objective lens simplifies the design of the…
Non-contact thermal measurements of VUV optics
Granted: November 27, 2018
Patent Number:
10139283
Methods and systems for performing non-contact temperature measurements of optical elements with long wavelength infrared light are described herein. The optical elements under measurement exhibit low emissivity to long wavelength infrared light and are often highly reflective or highly transmissive to long wavelength infrared light. In one aspect, a material coating having high emissivity, low reflectivity, and low transmission at long wavelength IR wavelengths is disposed over selected…
Process condition based dynamic defect inspection
Granted: November 20, 2018
Patent Number:
10133263
Defect inspection methods and systems that use process conditions to dynamically determine how to perform defect inspections during a semiconductor manufacturing process are disclosed. A defect inspection method may include: obtaining process conditions from a process tool utilized to process at least one wafer; determining whether to perform defect inspection of a layer, a wafer, or a high risk area/spot within the at least one wafer based on the process conditions obtained; bypassing…
Electron source
Granted: November 20, 2018
Patent Number:
10133181
An electron source is formed on a silicon substrate having opposing first and second surfaces. At least one field emitter is prepared on the second surface of the silicon substrate to enhance the emission of electrons. To prevent oxidation of the silicon, a thin, contiguous boron layer is disposed directly on the output surface of the field emitter using a process that minimizes oxidation and defects. The field emitter can take various shapes such as pyramids and rounded whiskers. One or…
Apparatus and methods for finding a best aperture and mode to enhance defect detection
Granted: November 20, 2018
Patent Number:
10132760
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…
Defect sensitivity of semiconductor wafer inspectors using design data with wafer image data
Granted: November 13, 2018
Patent Number:
10127651
Criticality of a detected defect can be determined based on context codes. The context codes can be generated for a region, each of which may be part of a die. Noise levels can be used to group context codes. The context codes can be used to automatically classify a range of design contexts present on a die without needing certain information a priori.