Tokyo Electron Limited

Therma-Wave, Inc.

Sensys Instruments Corporation

Kla Tencor Corporation

Leland Stanford Junior University

Fred E Stanke

Adam Eales Norton

Kenneth C Johnson

Abdurrahman Sezginer

Edric Tong

Talat Fatima Hasan

Michael Weber

Clinton Carlisle

Holger Tuitje

Elliot Burke

Hung Pham

James M Cahill

Douglas E Ruth

Butrus Thomas Khuri-Yakub

Hung The Pham

Rodney C Smedt

Michael Weber-Grabau

Shigeru Nagano

Mehdi Vaez-Iravani

Mark Armstrong McCord

Stanley E Stokowski

Christopher Sears

Fahrettin Levent Degertekin

Scott Allen Young

Douglas K Masnaghetti

David Alles

Richard R Simmons

B T Khuri-Yakub

Hung V Pham

Badru D Hyatt

Ilya Toytman

Ivelin A Anguelov

Gregg Anthony Inderhees

Optical inspection methods and apparatus for high-resolution photomasks using only a test image. A filter is applied to an image signal received from radiation that is transmitted by or reflected from a photomask having a test image. The filter may be implemented using programmed control to adjust and control filter conditions, illumination conditions, and magnification conditions.

Inspecting high-resolution photolithography masks

Embodiments of the present disclosure are directed to an electron beam imaging/inspection apparatus having an electron source device to direct flood electrons on a sample immediately before image acquisition or inspection. The apparatus comprises a first device configured to charge a sample in a first mode, wherein the first device includes an electron source configured to provide a flood beam of charged particles to a first area of the sample. The apparatus also comprises a second device configured to generate a primary beam of electrons and characterize an interaction between the primary beam and a second area of the sample within the first area in a second mode. The apparatus is configured to switch from the first mode to the second mode less than 1 second.

Inspection site preparation

A zoned order sorting filter for a spectrometer in a semiconductor metrology system is disclosed with reduced light dispersion at the zone joints. The order sorting filter comprises optically-transparent layers deposited underneath, or on top of thin-film filter stacks of the order sorting filter zones, wherein the thicknesses of the optically-transparent layers are adjusted such that the total optical lengths traversed by light at a zone joint are substantially equal in zones adjacent the zone joint. A method for wavelength to detector array pixel location calibration of spectrometers is also disclosed, capable of accurately representing the highly localized nonlinearities of the calibration curve in the vicinity of zone joints of an order sorting filter.

Diffraction order sorting filter for optical metrology

Calibration method for optical metrology

An optical measurement system for evaluating a sample has a motor-driven rotating mechanism coupled to an azimuthally rotatable measurement head, allowing the optics to rotate with respect to the sample. A polarimetric scatterometer, having optics directing a polarized illumination beam at non-normal incidence onto a periodic structure on a sample, can measure optical properties of the periodic structure. An E-O modulator in the illumination path can modulate the polarization. The head optics collect light reflected from the periodic structure and feed that light to a spectrometer for measurement. A beamsplitter in the collection path can ensure both S and P polarization from the sample are separately measured. The measurement head can be mounted for rotation of the plane of incidence to different azimuthal directions relative to the periodic structures. The instrument can be integrated within a wafer process tool in which wafers may be provided at arbitrary orientation.

Polarimetric scatterometry methods for critical dimension measurements of periodic structures

Optical metrology tools in a fleet of optical metrology tools can be matched using transforms. In particular, a first set of measured diffraction signals is obtained. The first set of measured diffraction signals was measured using a first optical metrology tool from the fleet of optical metrology tools. A second set of measured diffraction signals is obtained. The second set of diffraction signals was measured using a second optical metrology tool from the fleet of optical metrology tools. A reference diffraction signal is obtained. A first transform is generated based on the first set of measured diffraction signals and the reference diffraction signal. A second transform is generated based on the second set of measured diffraction signals and the reference diffraction signal.

Matching optical metrology tools using diffraction signals

Optical metrology tools in a fleet of optical metrology tools can be matched using transforms. In particular, a first set of hypothetical profiles of one or more structures is obtained. The first set of hypothetical profiles was determined based on a first set of measured diffraction signals measured using a first optical metrology tool from the fleet of optical metrology tools. A second set of hypothetical profiles of the structure is obtained. The second set of hypothetical profiles was determined based on a second set of measured diffraction signals measured using a second optical metrology tool from the fleet of optical metrology tools. A reference profile is obtained. A first transform is generated based on the first set of hypothetical profiles and the reference profile. A second transform is generated based on the second set of hypothetical profiles and the reference profile. A first hypothetical profile is obtained, where the first hypothetical profile was determined using the first optical metrology tool. A second hypothetical profile is obtained, where the second hypothetical profile was determined using the second optical metrology tool. The first hypothetical profile is transformed into a first transformed hypothetical profile using the first transform. The second hypothetical profile is transformed into a second transformed hypothetical profile using the second transform.

Matching optical metrology tools using hypothetical profiles

A small-spot imaging, spectrometry instrument for measuring properties of a sample has a polarization-scrambling element, such as a birefringent plate depolarizer, incorporated between the polarization-introducing components of the system, such as the beamsplitter, and the microscope objective of the system. The plate depolarizer varies polarization with wavelength, and may be a Lyot depolarizer with two plates, or a depolarizer with more than two plates (such as a three-plate depolarizer). Sinusoidal perturbation in the resulting measured spectrum can be removed by data processing techniques or, if the depolarizer is thick or highly birefringent, the perturbation may be narrower than the wavelength resolution of the instrument.

Small-spot spectrometry instrument with reduced polarization and multiple-element depolarizer therefor

This invention is an apparatus for imaging metrology, which in particular embodiments may be integrated with a processor station such that a metrology station is apart from but coupled to a process station. The metrology station is provided with a first imaging camera with a first field of view containing the measurement region. Alternate embodiments include a second imaging camera with a second field of view. Preferred embodiments comprise a broadband ultraviolet light source, although other embodiments may have a visible or near infrared light source of broad or narrow optical bandwidth. Embodiments including a broad bandwidth source typically include a spectrograph, or an imaging spectrograph. Particular embodiments may include curved, reflective optics or a measurement region wetted by a liquid. In a typical embodiment, the metrology station and the measurement region are configured to have 4 degrees of freedom of movement relative to each other.

Apparatus for imaging metrology

A database interpolation method is used to rapidly calculate a predicted optical response characteristic of a diffractive microstructure as part of a real-time optical measurement process. The interpolated optical response is a continuous and (in a preferred embodiment) smooth function of measurement parameters, and it matches the theoretically-calculated optical response at the database-stored interpolation points.

Database interpolation method for optical measurement of diffractive microstructures

A method of measuring at least one parameter associated with a portion of a sample having formed thereon one or more structures with at least two zones each having an associated zone reflectance property. The method includes the steps of illuminating the zones with broadband light, and measuring at least one reflectance property of light reflected from the at least two zones. The measurement includes a substantial portion of non-specularly scattered light, thereby increasing the quality of the measurement. The method further includes the step of fitting a parameterized model to the measured reflectance property. The parameterized model mixes the zone reflectance properties of the zones to account for partially coherent light interactions between the two zones.

Method of measuring meso-scale structures on wafers

Growing community of inventors

Cupertino, CA, United States of America

Fred E Stanke