KLA-Tencor Patent Grants

Determining coordinates for an area of interest on a specimen

Granted: November 13, 2018
Patent Number: 10127653
Methods and systems for determining coordinates for an area of interest on a specimen are provided. One system includes one or more computer subsystems configured for, for an area of interest on a specimen being inspected, identifying one or more targets located closest to the area of interest. The computer subsystem(s) are also configured for aligning one or more images for the one or more targets to a reference for the specimen. The image(s) for the target(s) and an image for the area…

Defect detection and classification based on attributes determined from a standard reference image

Granted: November 13, 2018
Patent Number: 10127652
Systems and methods for classifying defects detected on a wafer are provided. One method includes detecting defects on a wafer based on output generated for the wafer by an inspection system. The method also includes determining one or more attributes for at least one of the defects based on portions of a standard reference image corresponding to the at least one of the defects. The method further includes classifying the at least one of the defects based at least in part on the one or…

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.

Inspection systems and techniques with enhanced detection

Granted: November 13, 2018
Patent Number: 10126251
Disclosed are methods and apparatus for inspecting semiconductor samples. On an inspection tool, a plurality of different wavelength ranges is selected for different layers of interest of one or more semiconductor samples based on whether such different layers of interest have an absorber type material present within or near such different layers of interest. On the inspection tool, at least one incident beam is directed at the different wavelength ranges towards the different layers of…

Back-illuminated sensor with boron layer

Granted: November 6, 2018
Patent Number: 10121914
An inspection system including an optical system (optics) to direct light from an illumination source to a sample, and to direct light reflected/scattered from the sample to one or more image sensors. At least one image sensor of the system is formed on a semiconductor membrane including an epitaxial layer having opposing surfaces, with circuit elements formed on one surface of the epitaxial layer, and a pure boron layer on the other surface of the epitaxial layer. The image sensor may…

Power-scalable nonlinear optical wavelength converter

Granted: November 6, 2018
Patent Number: 10120262
A system includes a nonlinear crystal positioned such that a focus of a laser beam is outside the nonlinear crystal in at least one plane perpendicular to a beam propagation direction of the laser beam. The nonlinear crystal is disposed in a crystal mount assembly. A laser beam may be directed at the nonlinear crystal for wavelength conversion. The system may be used as a deep-UV wavelength converter.

Convolutional neural network-based mode selection and defect classification for image fusion

Granted: October 30, 2018
Patent Number: 10115040
Systems and methods for classifying defects using hot scans and convolutional neural networks (CNNs) are disclosed. Primary scanning modes are identified by a processor and a hot scan of a wafer is performed. Defects of interest and nuisance data are selected and images of those areas are captured usa7ing one or more secondary scanning modes. Image sets are collected and divided into subsets. CNNs are trained using the image subsets. An ideal secondary scanning mode is determined and a…

Apparatus and methods for optics protection from debris in plasma-based light source

Granted: October 16, 2018
Patent Number: 10101664
Disclosed are methods and apparatus for generating an illumination beam. In one embodiment, the apparatus includes a vacuum chamber configured to hold a target material, an optical element positioned within the vacuum chamber or within a wall of such vacuum chamber, and an illumination source system for generating at least one excitation source that is focused on the target in the vacuum chamber for generating a plasma in the vacuum chamber so as to produce illumination radiation. The…

Methods and apparatus for determining focus

Granted: October 16, 2018
Patent Number: 10101674
Disclosed are apparatus and methods for determining optimal focus for a photolithography system. A plurality of optical signals are acquired from a particular target located in a plurality of fields on a semiconductor wafer, and the fields were formed using different process parameters, including different focus values. A feature is extracted from the optical signals related to changes in focus. A curve is fitted to the extracted feature of the optical signals as a function of focus. An…

Statistical model-based metrology

Granted: October 16, 2018
Patent Number: 10101670
Methods and systems for creating a measurement model based on measured training data are presented. The trained measurement model is used to calculate process parameter values, structure parameter values, or both, directly from measured data collected from other wafers. The measurement models receive measurement data directly as input and provide process parameter values, structure parameter values, or both, as output. The measurement model enables the direct measurement of process…

Self-moiré target design principles for measuring unresolved device-like pitches

Granted: October 16, 2018
Patent Number: 10101592
Metrology targets and methods are provided, which provide self-Moiré measurements of unresolved target features, i.e., interaction of electromagnetic fields re-scattered off elements within a single target layer provides signals with Moiré pitches that are measurable, although the actual target pitches are unresolved and possibly device-like. Targets comprise cell(s) with interlaced lines of elements having different device-like pitches which are selected to yield resolved Moiré…

System and method for rejuvenating an imaging sensor degraded by exposure to extreme ultraviolet or deep ultraviolet light

Granted: October 9, 2018
Patent Number: 10096478
The present invention for imaging sensor rejuvenation may include a rejuvenation illumination system configured to selectably illuminate a portion of an imaging sensor of an imaging system with illumination suitable for at least partially rejuvenating the imaging sensor degraded by exposure to at least one of extreme ultraviolet light or deep ultraviolet light; and a controller communicatively coupled to the rejuvenation illumination system and configured to direct the rejuvenation…

Electron beam apparatus with high resolutions

Granted: October 9, 2018
Patent Number: 10096447
A magnetic gun lens and an electrostatic gun lens can be used in an electron beam apparatus and can help provide high resolutions for all usable electron beam currents in scanning electron microscope, review, and/or inspection uses. An extracted beam can be directed at a wafer through a beam limiting aperture using the magnetic gun lens. The electron beam also can pass through an electrostatic gun lens after the electron beam passes through the beam limiting aperture.

Systems and methods for fabricating metrology targets with sub-resolution features

Granted: October 9, 2018
Patent Number: 10095122
A lithography system includes an illumination source, a pattern mask, and an optical element configured to expose a sample with an image of the pattern mask for the fabrication of one or more printed device structures and one or more metrology target structures. The pattern mask includes a device pattern mask area and a metrology target pattern mask area. The device pattern mask area includes a set of device pattern elements distributed with a device pitch. The metrology target pattern…

Optimizing the utilization of metrology tools

Granted: October 9, 2018
Patent Number: 10095121
Methods and corresponding metrology modules and systems, which measure metrology parameter(s) of a previous layer of a metrology target and/or an alignment mark, prior to producing a current layer of the metrology target, derive merit figure(s) from the measured metrology parameter(s) to indicate an inaccuracy, and compensate for the inaccuracy to enhance subsequent overlay measurements of the metrology target. In an example embodiment, methods and corresponding metrology modules and…

Multi-surface specular reflection inspector

Granted: October 9, 2018
Patent Number: 10094787
An optical inspector includes a time varying beam reflector, a radiating source that irradiates the time varying beam reflector, a telecentric scan lens configured to direct the radiation reflected by the time varying beam reflector onto a first surface of a transparent sample, a first detector that receives at least a portion of top surface specular reflection, a second detector that receives at least a portion of the bottom surface specular reflection. A turning mirror may also be…

Method of improving lateral resolution for height sensor using differential detection technology for semiconductor inspection and metrology

Granted: October 2, 2018
Patent Number: 10088298
A system that can be used for semiconductor height inspection and metrology includes a complementary plate that is used with a beam splitter to create desired astigmatism and to remove chromatic aberration. Simultaneous optimization of lateral resolution and sensitivity can be enabled. The complementary plate can be made of the same material and have the same thickness as the beam splitter.

Method and system for aberration correction in an electron beam system

Granted: October 2, 2018
Patent Number: 10090131
An electron-optical system for performing electron microscopy is disclosed. The system includes an electron beam source configured to generate a primary electron beam. The system includes a source lens, a condenser lens and an objective lens disposed along an optical axis. The system includes a first Wien filter disposed along the optical axis and a second Wien filter disposed along the optical axis. The first Wien filter and the second Wien filter are disposed between the source lens…

Spectral matching based calibration

Granted: October 2, 2018
Patent Number: 10088413
Methods and systems for calibrating system parameter values of a target inspection system are presented. Spectral Error Based Calibration (SEBC) increases consistency among inspection systems by minimizing differences in the spectral error among different inspection systems for a given specimen or set of specimens. The system parameter values are determined such that differences between a spectral error associated with a measurement of a specimen by the target inspection system and a…

Haze and defect distribution and aperture configuration in surface metrology inspectors

Granted: October 2, 2018
Patent Number: 10088345
The present disclosure is directed to a method for designing an aperture in a mask for inspecting a wafer. The method includes the steps of scanning a collection plane of the wafer at a plurality of points and collecting data for at least a part of the wafer. The method also includes the step of mapping the data. A further step of the method includes configuring the aperture based on the mapped data.