Kla Tencor Corporation

Kla-Tencor Technologies Corporation

Other

Boris Golovanevsky

Michael E Adel

Mark Ghinovker

Daniel Kandel

Walter Dean Mieher

Michael Friedmann

John Fielden

Ady Levy

Noah Bareket

Ian R Smith

Anatoly Fabrikant

Christopher F Bevis

Dan Wack

Thaddeus Gerard Dziura

Noam Sapiens

Kenneth P Gross

Piotr S Zalicki

Paola Dececco

Amnon Manassen

Vladimir Levinski

Chris Mack

Yoel Feler

Nadav Gutman

Daria Negri

Moshe E Preil

Barak Bringoltz

Ohad Bachar

Joel L Seligson

John Charles Robinson

Alexander Svizher

Meir Aloni

Pavel Izikson

Jiyou Fu

Guy Ben Dov

Paola deCecco

Jorge Poplawski

Elyakim Kassel

Hadar Shalmoni

Paykin Irina

Ken Gross

Shakar Krishnan

Noam Knoll

Noam Gluzer

Ian Smith

Baruch Moshe

Focusing methods and modules are provided for metrology tools and systems. Methods comprise capturing image(s) of at least two layers of a ROI in an imaging target, binning the captured image(s), deriving a focus shift from the binned captured image(s) by comparing the layers, and calculating a focus position from the derived focus shift. Disclosed methods are direct, may be carried out in parallel to a part of the overlay measurement process and provide fast and simple focus measurements that improve metrology performance.

Direct focusing with image binning in metrology tools

Metrology overlay targets are provided, as well as method of monitoring process shortcomings. Targets comprise periodic structures, at least one of which comprising repeating asymmetric elements along a corresponding segmentation direction of the periodic structure. The asymmetry of the elements may be designed in different ways, for example as repeating asymmetric sub-elements along a direction perpendicular to the segmentation direction of the elements. The asymmetry of the sub-elements may be designed in different ways, according to the type of monitored process shortcomings, such as various types of hot spots, line edge shortening, process windows parameters and so forth. Results of the measurements may be used to improve the process and/or increase the accuracy of the metrology measurements.

Hot spot and process window monitoring

Metrology tool stage configurations and respective methods are provided, which comprise a pivoted connection arranged to receive a wafer and enable rotation thereof about a pivot; a radial axis arranged to radially move the rotatable pivoted connection attached thereto; and optics having a stationary part configured to generate a collimated illumination beam. For example, the optics may be stationary and the radial axis may be centrally rotated to enable stage operation without requiring additional space for guiding systems. In another example, a part of the optics may be rotatable, when configured to receive illumination via a mechanically decoupled or empty region, receive power and control wirelessly and deliver data wirelessly. The disclosed configurations provide more compact and more robust stages which efficiently handle large wafers. Stage configurations may be horizontal or vertical, the latter further minimizing the tool's footprint.

Metrology tool stage configurations and operation methods

Systems and methods are provided which derive target characteristics from interferometry images taken at multiple phase differences between target beams and reference beams yielding the interferometry images. The illumination of the target and the reference has a coherence length of less than 30 microns to enable scanning the phase through the coherence length of the illumination. The interferometry images are taken at the pupil plane and/or in the field plane to combine angular and spectroscopic scatterometry data that characterize and correct target topography and enhance the performance of metrology systems.

Phase characterization of targets

Metrology tools are provided, which comprise both active and passive vibration isolation devices, passive or active isolation systems such as constrained layer dampers, particle impact dampers or liquid impact dampers, and/or noise cancellation transducers, combined in different supporting structures of the metrology tool to dampen and reduce vibrations at a wide range of frequencies and intensities, and to which frequency range spectral analysis and optimization may be applied to determine specific tool configurations according to the provided principles.

Metrology target indentification, design and verification

A scatterometry tool including an illumination source for directing a light beam into a first optical beam shaping and positioning element at an illumination pupil plane of the tool where the light beam is modulated and directed to an objective lens system having a high numerical aperture. The objective receiving the modulated light beam and directing it onto a target to generate a scattering signal. The objective lens collects the scattering signal and directs it to a second optical beam shaping and positioning element at a collection pupil plane where the signal is modulated and then directed to detectors for receiving and processing the signal to determine surface characteristics of the target.

Flexible scatterometry metrology system and method

In one embodiment, a surface inspection system comprises a radiation source that emits a broadband radiation beam, a radiation directing assembly to target radiation onto a surface of an object, the radiation directing assembly comprising a radiation collection assembly to collect radiation reflected from the surface of the object, the radiation collection assembly comprising at least one multi-chip detector array assembly positioned within a field of view of the inspection system.

Multichip CCD camera inspection system

Disclosed are techniques, apparatus, and targets for determining overlay error between two layers of a sample. A plurality of targets is provided. Each target includes a portion of the first and second structures and each is designed to have an offset between its first and second structure portions. The targets are illuminated with electromagnetic radiation to thereby obtain spectra from each target at a &#x2212;1diffraction order and a +1diffraction order. It is determined whether there are any overlay error between the first structures and the second structures using a scatterometry technique based on the detected spectra by (i) for each target, determining a first differential intensity between the &#x2212;1diffraction order and a +1diffraction order, (ii) for a plurality of pairs of targets each having a first target and a second target, determining a second differential intensity between the first differential intensity of the first target and the first differential intensity of the second target, and (iii) determining any overlay error between the first structures and the second structures using a scatterometry technique based on the second differential intensities determined from each target pair.

Apparatus and methods for detecting overlay errors using scatterometry

An overlay method for determining the overlay error of a device structure formed during semiconductor processing is disclosed. The overlay method includes producing calibration data that contains overlay information relating the overlay error of a first target at a first location to the overlay error of a second target at a second location for a given set of process conditions. The overlay method also includes producing production data that contains overlay information associated with a production target formed with the device structure. The overlay method further includes correcting the overlay error of the production target based on the calibration data.

Overlay metrology and control method

Disclosed are techniques, apparatus, and targets for determining overlay error between two layers of a sample. Target A is designed to have an offset Xa between its first and second structures portions; target B is designed to have an offset Xb; target C is designed to have an offset Xc; and target D is designed to have an offset Xd. Each of the offsets Xa, Xb, Xc and Xd is preferably different from zero; Xa is an opposite sign and differ from Xb; and Xc is an opposite sign and differs from Xd. The targets A, B, C and D are illuminated with electromagnetic radiation to obtain spectra S, S, S, and Sfrom targets A, B, C, and D, respectively. Any overlay error between the first structures and the second structures is then determined using a linear approximation based on the obtained spectra S, S, S, and S.

Embodiments of the invention include a scatterometry target for use in determining the alignment between substrate layers. A target arrangement is formed on a substrate and comprises a plurality of target cells. Each cell has two layers of periodic features constructed such that an upper layer is arranged above a lower layer and configured so that the periodic features of the upper layer have an offset and/or different pitch than periodic features of the lower layer. The pitches are arranged to generate a periodic signal when the target is exposed to an illumination source. The target also includes disambiguation features arranged between the cells and configured to resolve ambiguities caused by the periodic signals generated by the cells when exposed to the illumination source.

Disclosed is a method of determining an overlay error between two layers of a multiple layer sample. For each of a plurality of periodic targets target that each have a first structure formed from a first layer and a second structure formed from a second layer of the sample, a plurality of optical signals are measured at a plurality of incident angles, wherein there are predefined offsets between the first and second structures. An overlay error is then determined between the first and second structures by analyzing the measured optical signals at the plurality of incident angles from the periodic targets using a scatterometry overlay technique based on the predefined offsets without using a calibration operation.

Systems and methods are disclosed for using ellipsometer configurations to measure the partial Mueller matrix and the complete Jones matrix of a system that may be isotropic or anisotropic. In one embodiment two or more signals, which do not necessarily satisfy any symmetry assumptions individually, are combined into a composite signal which satisfies a symmetry assumption. The individual signals are collected at two or more analyzer angles. Symmetry properties of the composite signals allow easy extraction of overlay information for any relative orientation of the incident light beam with respect to a 1D grating target, as well as for targets comprising general 2D gratings. Signals of a certain symmetry property also allow measurement of profile asymmetry in a very efficient manner. In another embodiment a measurement methodology is defined to measure only signals which satisfy a symmetry assumption. An optional embodiment comprises a single polarization element serving as polarizer and analyzer. Another optional embodiment uses an analyzing prism to simultaneously collect two polarization components of reflected light.

Measuring overlay and profile asymmetry using symmetric and anti-symmetric scatterometry signals

Growing community of inventors

Haifa, Israel

Boris Golovanevsky