Kla-tencor Technologies Corporation

Kla Tencor Corporation

Kla Corporation

Zhiwei Xu

Thomas G Miller

Gregory S Horner

Amin Samsavar

Christian Wolters

Jianou Shi

Stephen Biellak

Juergen Reich

Sergio Edelstein

Qing Li

Bret Whiteside

John M Schmidt

Rainer Schierle

Frank Li

Xiaofeng Hu

George J Kren

Daniel Ivanov Kavaldjiev

Anatoly Romanovsky

Kurt Lindsay Haller

Yury Yuditsky

Aleksey Petrenko

Patrick Stevens

Mehdi Vaez-Iravani

Guoheng Zhao

Shiyou Pei

John D Alexander

Donald Pettibone

Jenn-Kuen Leong

Chunsheng J Huang

Steve Yifeng Cui

Jeffrey Alan Rzepiela

Chunhai Wang

Chuanyong Huang

Jijen Vazhaeparambil

Sam Shamouilian

J K Leong

Mandar Paranjape

Yifeng Cui

Kwan Auyeung

Arun Srivatsa

Greg Horner

Steven Weinzierl

Kurt Haller

Timothy Swisher

A semiconductor wafer is inspected using a main laser beam and a secondary laser beam. The secondary laser beam leads the main laser beam and has lower power than the main laser beam. Using the secondary laser beam, a particle is detected on the semiconductor wafer having a size that satisfies a threshold. In response to detecting the particle, the power of the main laser beam and the power of the secondary laser beam are reduced. The particle passes through the main laser beam with the main laser beam at reduced power. After the particle has passed through the main laser beam with the main laser beam at the reduced power, the power of the main laser beam and the power of the secondary laser beam are restored in a controlled manner that is slower than a single step.

Large-particle monitoring with laser power control for defect inspection

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

Methods and systems for detecting and classifying defects based on the phase of dark field scattering from a sample are described herein. In some embodiments, throughput is increased by detecting and classifying defects with the same optical system. In one aspect, a defect is classified based on the measured relative phase of scattered light collected from at least two spatially distinct locations in the collection pupil. The phase difference, if any, between the light transmitted through any two spatially distinct locations at the pupil plane is determined from the positions of the interference fringes in the imaging plane. The measured phase difference is indicative of the material composition of the measured sample. In another aspect, an inspection system includes a programmable pupil aperture device configured to sample the pupil at different, programmable locations in the collection pupil.

Methods and systems for optical surface defect material characterization

Systems, methods, and apparatuses are disclosed herein for directing, using an optical arrangement including one or more lenses, a main beam and a leading beam toward a specimen such that the main beam is incident on the specimen at a main beam incidence and the leading beam is incident on the specimen at a leading beam incidence. The main beam intensity is greater than a leading beam intensity of the leading beam. A TDI sensor receives electromagnetic radiation from the leading beam incidence, thereby generating a first accumulated charge portion, and receives electromagnetic radiation from the main beam incidence, thereby generating a second accumulated charge portion. A processor maps the first accumulated charge portion to a first FOV, thereby yielding leading beam data, and maps the second accumulated charge portion to a second FOV, thereby yielding main beam data.

Systems and methods for advanced defect ablation protection

An inspection system utilizing an air scatter standard includes one or more illumination sources to generate a beam of illumination, illumination optics configured to focus the beam of illumination into a volume of air contained within a chamber of an inspection chamber, one or more collection optics configured to collect a portion of illumination scattered from the volume of air, a detector configured to receive the collected portion of illumination from the one or more collection optics, a controller including one or more processors, communicatively coupled to the detector, configured to execute a set of program instructions to receive one or more signals from the detector and determine a state of the beam of illumination at one or more times based on a comparison between at least one of the intensity or polarization of the illumination scattered from the volume of air and a predetermine air scatter standard.

Air scattering standard for light scattering based optical instruments and tools

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

A beam shaper for an optical inspection tool includes a focal lens to focus an optical beam onto a target at an oblique angle of incidence and a phase modulator to substantially flatten a top of the optical beam in the plane of the target when the optical beam is focused onto the target at the oblique angle of incidence.

Inspection-beam shaping on a sample surface at an oblique angle of incidence

A system includes a beam steering assembly configured to adjust an incident beam to form a corrected beam; a beam monitoring assembly configured to generate monitoring data for the corrected beam including one or more offset parameters of the corrected beam; and a controller configured to store one or more zero parameters of the corrected beam, calculate at least one difference between the one or more zero parameters and the one or more offset parameters of the corrected beam, determine one or more beam position adjustments of the incident beam based on the at least one difference between the one or more zero parameters and the one or more offset parameters of the corrected beam, and direct the beam steering assembly via one or more motor drivers to actuate one or more motors to adjust the incident beam to form the corrected beam.

System and method for compensation of illumination beam misalignment

Methods and systems for reshaping the beam intensity distribution of an illumination light supplied to a specimen under inspection are presented. A scanning surface inspection system includes a beam shaping element that flattens the beam intensity distribution of a beam of light generated by an illumination source. The reshaped illumination light is directed to the wafer surface over an illumination spot. With a flattened beam intensity distribution, the incident beam power can be increased without the beam intensity exceeding the damage threshold of the wafer at any particular location. In addition, the illumination spot is shaped by the beam shaping element to have a variable beam width in a direction parallel to the inspection track. The location of a defect within an inspection area having a variable beam width is estimated based on an analysis of the output of the detector.

Inspection beam shaping for improved detection sensitivity

The disclosure is directed to a system and method of managing illumination energy applied to illuminated portions of a scanned wafer to mitigate illumination-induced damage without unnecessarily compromising SNR of an inspection system. The wafer may be rotated at a selected spin frequency for scanning wafer defects utilizing the inspection system. Illumination energy may be varied over at least one scanned region of the wafer as a function of radial distance of an illuminated portion from the center of the wafer and the selected spin frequency of the wafer. Illumination energy may be further applied constantly over one or more scanned regions of the wafer beyond a selected distance from the center of the wafer.

Illumination energy management in surface inspection

The disclosure is directed to a system and method for inspecting a spinning sample by substantially simultaneously scanning multiple spots on a surface of the sample utilizing a plurality of illumination beams. Portions of illumination reflected, scattered, or radiated from respective spots on the surface of the sample are collected by at least one detector array. Information associated with at least one defect of the sample is determined by at least one computing system in communication with the detector array. According to various embodiments, at least one of scan pitch, spot size, spot separation, and spin rate is controlled to compensate pitch error due to tangential spot separation.

Multi-spot defect inspection system

Systems configured to perform a non-contact method for determining a property of a specimen are provided. One system configured to perform a non-contact method for determining a property of a specimen includes a focused biasing device configured to provide a stimulus to a focused spot on the specimen. The system also includes a sensor configured to measure a parameter of a measurement spot on the specimen. The measurement spot overlaps the focused spot. The system further includes a processor configured to determine the property of the specimen from the parameter.

Systems configured to perform a non-contact method for determining a property of a specimen

Systems and methods for determining a property of a specimen are provided. The specimen may be a product wafer. The method may include biasing a focused spot on the specimen. The method may also include measuring a parameter of a measurement spot on the specimen. The measurement spot may overlap the focused spot. In addition, the method may include determining the property of the specimen from the measured parameter. Systems and methods for varying the performance of a corona source are also provided. The method may include altering a property of the environment within the corona source. The property may include, but is not limited to, temperature, pressure, humidity, and/or partial pressure of a gas within the corona source.

Contactless charge measurement of product wafers and control of corona generation and deposition

A method for determining a property of an insulating film is provided. The method may include obtaining a charge density measurement of the film, a surface voltage potential of the film relative to a bulk voltage potential of the substrate, and a rate of voltage decay of the film. The method may also include determining the property of the film using the charge density, the surface voltage potential, and the rate of voltage decay. A method for determining a thickness of an insulating film is provided. The method may include depositing a charge on the film, measuring a surface voltage potential of the film relative to a bulk voltage potential of the substrate, and measuring a rate of voltage decay of the film. The method may also include determining a thickness of the film using the rate of voltage decay and a theoretical model relating to current leakage and film thickness.

Methods and systems for determining a property of an insulating film

Growing community of inventors

Sunnyvale, CA, United States of America

Zhiwei Xu