Kla Tencor Corporation

Kla Corporation

Kla-tencor Technologies Corporation

Daniel Ivanov Kavaldjiev

Stephen Biellak

Anatoly Romanovsky

Guoheng Zhao

David W Shortt

George J Kren

Christopher F Bevis

Rodney C Smedt

Dieter Mueller

Paul J Sullivan

Hans J Hansen

Mehdi Vaez-Iravani

Christian Wolters

Ivan Maleev

Bret Whiteside

Jenn-Kuen Leong

Rainer Schierle

John Fielden

Donald Pettibone

Juergen Reich

Yury Yuditsky

Dirk Woll

Yung-Ho Alex Chuang

Xuefeng Liu

Zhiwei Xu

Brian L Haas

Aleksey Petrenko

Alexander Belyaev

Prasanna Dighe

Andrew Steinbach

Louis Vintro

David Lee Brown

Haiguang Chen

Shouhong Tang

Stuart L Friedman

Qing Li

David L Chen

Jehn-Huar Chern

Kurt Lindsay Haller

Alexander Buettner

Guowu Zheng

Devis Contarato

Amith Kumar Murali

Chuanyong Huang

Chunhai Wang

Dengpeng Chen

Frank Li

Jijen Vazhaeparambil

Mike D Kirk

Steve Zamek

Richard Fong

Jien Cao

Dieter Muller

Geroge Kren

Steven Biellak

Dong Chen

Brian Haas

A dark-field optical system may include a rotational objective lens assembly with a dark-field objective lens to collect light from a sample within a collection numerical aperture, where the dark-field objective lens includes an entrance aperture and an exit aperture at symmetrically-opposed azimuth angles with respect to an optical axis, a rotational bearing to allow rotation of at least a part of the dark-field objective lens including the entrance aperture and the exit aperture around the optical axis, and a rotational driver to control a rotational angle of the entrance aperture. The system may also include a multi-angle illumination sub-system to illuminate the sample with an illumination beam through the entrance aperture at two or more illumination azimuth angles, where an azimuth angle of the illumination beam on the sample is selectable by rotating the objective lens to any of the two or more illumination azimuth angles.

Apparatus and method for rotating an optical objective

A system for analyzing a sample includes an illumination source with a plurality of transmitting optical fibers optically coupled to the illumination source and a detector with a plurality of receiving optical fibers optically coupled to the detector. The system further includes a plurality of probes coupled to respective ones of the plurality of transmitting optical fibers and respective ones of the plurality of receiving optical fibers. The plurality of probes are configured to illuminate respective portions of a surface of the sample and configured to receive illumination reflected, refracted, or radiated from the respective portions of the surface of the sample. The system may further include one or more switches and/or splitters configured to optically couple respective ones of the plurality of transmitting optical fibers to the illumination source and/or configured to optically couple respective ones of the plurality of receiving optical fibers to the detector.

Multi-spot analysis system with multiple optical probes

A system may include illumination optics to direct an illumination beam to a sample at an off-axis angle, collection optics to collect scattered light from the sample, and a phase mask located at a first pupil plane to provide different phase shifts for light in two or more pupil regions of a collection area to reshape a point spread function of light scattered from one or more particles on a surface of the sample. The system may further include a polarization rotator located at a second pupil plane, where the polarization rotator provides a spatially-varying polarization rotation angle selected to rotate light scattered from the surface of the sample to a selected polarization angle, a polarizer to reject light polarized along the selected polarization angle, and a detector to generate a dark-field image of the sample based on light passed by the polarizer.

Sensitive particle detection with spatially-varying polarization rotator and polarizer

A dark-field inspection system may include an illumination source to generate an illumination beam, illumination optics configured to direct the illumination beam to a sample at an off-axis angle along an illumination direction, collection optics to collect scattered light from the sample in response to the illumination beam in a dark-field mode, a polarization rotator located at a pupil plane of the one or more collection optics, where the polarization rotator provides a spatially-varying polarization rotation angle selected to rotate light scattered from a surface of the sample to a selected polarization angle, a polarizer aligned to reject light polarized along the selected polarization angle to reject the light scattered from a surface of the sample, and a detector to generate a dark-field image of the sample based on scattered light from the sample passed by the polarizer.

A dark field inspection system may include an illumination source to generate an illumination beam, one or more illumination optics to direct the illumination beam to a sample at an off-axis angle along an illumination direction, a detector, one or more collection optics to generate a dark-field image of the sample on the detector based on light collected from the sample in response to the illumination beam, and a radial polarizer located at a pupil plane of the one or more collection optics, where the radial polarizer rejects light with radial polarization with respect to an apex point in the pupil plane corresponding to specular reflection of the illumination beam from the sample.

Radial polarizer for particle detection

Stray and air scattered light can be reduced by configuring a size of the collection area of a sensor, which reduces a source of sensitivity-limiting noise in the system. By adjusting a size of the collection area, stray deep ultraviolet light and air-scattered deep ultraviolet light can be reduced. A servo can control a position of an illumination spot that is collected by the time delay and integration sensor.

Minimizing filed size to reduce unwanted stray light

Systems configured to inspect a wafer are provided. One system includes an illumination subsystem configured to direct pulses of light to an area on a wafer; a scanning subsystem configured to scan the pulses of light across the wafer; a collection subsystem configured to image pulses of light scattered from the area on the wafer to a sensor, wherein the sensor is configured to integrate a number of the pulses of scattered light that is fewer than a number of the pulses of scattered light that can be imaged on the entire area of the sensor, and wherein the sensor is configured to generate output responsive to the integrated pulses of scattered light; and a computer subsystem configured to detect defects on the wafer using the output generated by the sensor.

Wafer inspection

An inspection system and methods in which analog image data values (charges) captured by an image sensor are binned (combined) before or while being transmitted as output signals on the image sensor's output sensing nodes (floating diffusions), and in which an ADC is controlled to sequentially generate multiple corresponding digital image data values between each reset of the output sensing nodes. According to an output binning method, the image sensor is driven to sequentially transfer multiple charges onto the output sensing nodes between each reset, and the ADC is controlled to convert the incrementally increasing output signal after each charge is transferred onto the output sensing node. According to a multi-sampling method, multiple charges are vertically or horizontally binned (summed/combined) before being transferred onto the output sensing node, and the ADC samples each corresponding output signal multiple times. The output binning and multi-sampling methods may be combined.

Dark-field inspection using a low-noise sensor

A wafer scanning system includes imaging collection optics to reduce the effective spot size. Smaller spot size decreases the number of photons scattered by the surface proportionally to the area of the spot. Air scatter is also reduced. TDI is used to produce a wafer image based on a plurality of image signals integrated over the direction of linear motion of the wafer. An illumination system floods the wafer with light, and the task of creating the spot is allocated to the imaging collection optics.

TDI sensor in a darkfield system

Systems configured to inspect a wafer are provided. One system includes an illumination subsystem configured to simultaneously form multiple illumination areas on the wafer with substantially no illumination flux between each of the areas. The system also includes a scanning subsystem configured to scan the multiple illumination areas across the wafer. In addition, the system includes a collection subsystem configured to simultaneously and separately image light scattered from each of the areas onto two or more sensors. Characteristics of the two or more sensors are selected such that the scattered light is not imaged into gaps between the two or more sensors. The two or more sensors generate output responsive to the scattered light. The system further includes a computer subsystem configured to detect defects on the wafer using the output of the two or more sensors.

A system for inspecting specimens such as semiconductor wafers is provided. The system provides scanning of dual-sided specimens using a diffraction grating that widens and passes nth order (n&#x3e;0) wave fronts to the specimen surface and a reflective surface for each channel of the light beam. Two channels and two reflective surfaces are preferably employed, and the wavefronts are combined using a second diffraction grating and passed to a camera system having a desired aspect ratio. The system preferably comprises a damping arrangement which filters unwanted acoustic and seismic vibration, including an optics arrangement which scans a first portion of the specimen and a translation or rotation arrangement for translating or rotating the specimen to a position where the optics arrangement can scan the remaining portion(s) of the specimen. The system further includes means for stitching scans together, providing for smaller and less expensive optical elements.

Grazing and normal incidence interferometer having common reference surface

Methods and systems for enhancing the dynamic range of a high sensitivity inspection system are presented. The dynamic range of a high sensitivity inspection system is increased by directing a portion of the light collected from each pixel of the wafer inspection area toward an array of avalanche photodiodes (APDs) operating in Geiger mode and directing another portion of the light collected from each pixel of the wafer inspection area toward another array of photodetectors having a larger range. The array of APDs operating in Geiger mode is useful for inspection of surfaces that generate extremely low photon counts, while other photodetectors are useful for inspection of larger defects that generate larger numbers of scattered photons. In some embodiments, the detected optical field is split between two different detectors. In some other embodiments, a single detector includes both APDs operating in Geiger mode and other photodetectors having a larger range.

Sample inspection system detector

Methods, systems, and structures for monitoring incident beam position in a wafer inspection system are provided. One structure includes a feature formed in a chuck configured to support a wafer during inspection by the wafer inspection system. The chuck rotates the wafer in a theta direction and simultaneously translates the wafer in a radial direction during the inspection. An axis through the center of the feature is aligned with a radius of the chuck such that a position of the axis relative to an incident beam of the wafer inspection system indicates changes in the incident beam position in the theta direction.

Monitoring incident beam position in a wafer inspection system

A system for inspecting specimens such as semiconductor wafers is provided. The system provides scanning of dual-sided specimens using a diffraction grating that widens and passes nth order (n&#x3e;0) wave fronts to the specimen surface and a reflective surface for each channel of the light beam. Two channels and two reflective surfaces are preferably employed, and the wavefronts are combined using a second diffraction grating and passed to a camera system having a desired aspect ratio. The system preferably comprises a damping arrangement which filters unwanted acoustic and seismic vibration, including an optics arrangement which scans a first portion of the specimen and a translation or rotation arrangement for translating or rotating the specimen to a position where the optics arrangement can scan the remaining portion(s) of the specimen. The system further includes-means for stitching scans together, providing for smaller and less expensive optical elements.

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Santa Clara, CA, United States of America

Daniel Ivanov Kavaldjiev