Kla Tencor Corporation

Kla Corporation

Nuriel Amir

Eran Amit

Amnon Manassen

Vladimir Levinski

Roie Volkovich

Michael E Adel

Daniel Kandel

Tal Itzkovich

Mark Ghinovker

Yoel Feler

Barak Bringoltz

Raviv Yohanan

Tal Marciano

Amit Shaked

Andrew V Hill

Liran Yerushalmi

Guy Cohen

Barry Loevsky

Dana Klein

DongSub Choi

Boris Efraty

Ady Levy

Stilian Pandev

Leonid Poslavsky

Nadav Gutman

Ohad Bachar

John Charles Robinson

Mark Wagner

Amir Widmann

Tzahi Grunzweig

Dzmitry Sanko

Nadav Carmel

Evgeni Gurevich

Inna Tarshish-Shapir

David Gready

Tal Yaziv

Nimrod Shuall

Lilach Saltoun

Anat Marchelli

Noga Sella

Ido Adam

Ofer Zaharan

Tom Leviant

Tal Shusterman

Sergey Borodyansky

Sigalit Robinzon

Oded Kaminsky

Amir Handelman

Vidya Ramanathan

Janay Camp

Moshe Cooper

Roee Sulimarski

Eltsafon Ashwal

Berta Dinu

Mohamed El Kodadi

Dzimtry Sanko

Ze'ev Lindenfeld

Zeng Zhao

Mohammed El Kodadi

Metrology targets, production processes and optical systems are provided, which enable metrology of device-like targets. Supplementary structure(s) may be introduced in the target to interact optically with the bottom layer and/or with the top layer of the target and target cells configurations enable deriving measurements of device-characteristic features. For example, supplementary structure(s) may be designed to yield Moir&#xe9; patterns with one or both layers, and metrology parameters may be derived from these patterns. Device production processes were adapted to enable production of corresponding targets, which may be measured by standard or by provided modified optical systems, configured to enable phase measurements of the Moir&#xe9; patterns.

Device-like metrology targets

Targets, target elements and target design method are provided, which comprise designing a target structure to have a high contrast above a specific contrast threshold to its background in polarized light while having a low contrast below the specific contrast threshold to its background in non-polarized light. The targets may have details at device feature scale and be compatible with device design rules yet maintain optical contrast when measured with polarized illumination and thus be used effectively as metrology targets. Design variants and respective measurement optical systems are likewise provided.

Polarization measurements of metrology targets and corresponding target designs

The disclosure is directed to designing and using an overlay target with orthogonal underlayer dummyfill. According to various embodiments, an overlay target may include one or more segmented overlay pattern elements forming at least one overlay target structure. The overlay target may further include one or more inactive pattern elements forming at least one dummyfill target structure. Each of the one or more inactive pattern elements may include dummyfill segmented along an axis orthogonal to a segmentation axis of at least one proximately disposed overlay pattern element. In some embodiments, each of the target structures or layers may be formed from a separate process layer successively disposed upon a substrate, such as a silicon wafer. In some embodiments, the overlay and dummyfill target structures may be twofold or fourfold rotationally symmetric to allow for certain manufacturing or metrology advantages.

Overlay targets with orthogonal underlayer dummyfill

Methods are provided for deriving a partially continuous dependency of metrology metric(s) on recipe parameter(s), analyzing the derived dependency, determining a metrology recipe according to the analysis, and conducting metrology measurement(s) according to the determined recipe. The dependency may be analyzed in form of a landscape such as a sensitivity landscape in which regions of low sensitivity and/or points or contours of low or zero inaccuracy are detected, analytically, numerically or experimentally, and used to configure parameters of measurement, hardware and targets to achieve high measurement accuracy. Process variation is analyzed in terms of its effects on the sensitivity landscape, and these effects are used to characterize the process variation further, to optimize the measurements and make the metrology both more robust to inaccuracy sources and more flexible with respect to different targets on the wafer and available measurement conditions.

Method of analyzing and utilizing landscapes to reduce or eliminate inaccuracy in overlay optical metrology

Systems and method are provided for analyzing target, process and metrology configuration sensitivities to a wide range of parameters, according to external requirements or inner development and verification needs. Systems comprise the following elements. An input module is arranged to receive parameters relating to targets, target metrology conditions and production processes, to generate target data. A metrology simulation unit is arranged to simulate metrology measurements of targets from the target data and to generate multiple metrics that quantify the simulated target measurements. A sensitivity analysis module is arranged to derive functional dependencies of the metrics on the parameters and to define required uncertainties of the parameters with respect to the derived functional dependencies. Finally, a target optimization module is arranged to rank targets and target metrology conditions with respect to the simulated target measurements.

Target and process sensitivity analysis to requirements

Methods of designing metrology targets are provided, which comprise distinguishing target elements from their background area by segmenting the background area and optionally segmenting the target elements. The provided metrology targets may maintain a required feature size when measured yet be finely segmented to achieve process and design rules compatibility which results in higher accuracy of the metrology measurements. Particularly, all transitions between target features and adjacent background features may be designed to maintain a feature size of the features below a certain threshold.

Process compatible segmented targets and design methods

Metrology targets with supplementary structures in an intermediate layer

Imaging metrology targets and methods are provided, which combine one-dimensional (1D) elements designed to provide 1D imaging metrology signals along at least two measurement directions and two-dimensional (2D) elements designed to provide at least one 2D imaging metrology overlay signal. The target area of the 1D elements may enclose the 2D elements or the target areas of the 1D and 2D elements may be partially or fully congruent. The compound targets are small, possibly multilayered, and may be designed to be process compatible (e.g., by segmentation of the elements, interspaces between elements and element backgrounds) and possibly be produced in die. Two dimensional elements may be designed to be periodic to provide additional one dimensional metrology signals.

Compound imaging metrology targets

Metrology methods and targets are provided, for estimating inter-cell process variation by deriving, from overlay measurements of at least three target cells having different designed misalignments, a dependency of a measured inaccuracy on the designed misalignments (each designed misalignment is between at least two overlapping periodic structures in the respective target cell). Inaccuracies which are related to the designed misalignments are reduced, process variation sources are detected and targets and measurement algorithms are optimized according to the derived dependency.

Estimating and eliminating inter-cell process variation inaccuracy

Target designs methods and targets are provided, in which at least some of the differentiation between target elements and their background is carried out by segmenting either of them. Directed self-assembly (DSA) processes are used to generate fine segmentation, and various characteristics of the polymer lines and their guiding lines are used to differentiate target elements from their background. Target designs and design principles are disclosed in relation to the DSA process, as well as optimization of the DSA process to yield high metrology measurement accuracy in face of production inaccuracies. Furthermore, designs and methods are provided for enhancing and using ordered regions of a DSA-produced polymer surface as target elements and as hard masks for production processes. The targets and methods may be configured to enable metrology measurements using polarized light to distinguish target elements or DSA features.

Method and apparatus for direct self assembly in target design and production

Methods and systems are provided, which identify specified metrology target abnormalities using selected metrics and classify the identified target abnormalities geometrically to link them to corresponding sources of error. Identification may be carried out by deriving target signals such as kernels from specified regions of interest (ROIs) from corresponding targets on a wafer, calculating the metrics from the target signals using respective functions and analyzing the metrics to characterize the targets.

Method, system, and user interface for metrology target characterization

Methods and metrology tool modules embodying the methods are provided. Methods comprise measuring characteristics of intermediate features such as guiding lines in a directed self-assembly (DSA) process, deriving exposure parameters from the measured characteristics; and adjusting production parameters for producing consecutive target features according to the derived exposure parameters. The methods and modules enhance the accuracy of the DSA-produced structures and related measurements.

On-product derivation and adjustment of exposure parameters in a directed self-assembly process

Alignment of multi-beam pattern tools includes generating a test pattern having multiple features with a multi-beam patterning tool, acquiring an image standard associated with a test pattern standard, acquiring an image of a portion of the test pattern, comparing the portion of the image of the test pattern to the image standard to identify one or more irregularities between the portion of the image of the test pattern and the image standard, and adjusting one or more beams of the multi-beam patterning tool based on the one or more identified irregularities between the portion of the image of the test pattern and the image standard.

Alignment of multi-beam patterning tool

The subject application relates to metrology targets with filling elements that reduce inaccuracies and maintain contrast. The present invention provides a metrology target and a method to design the metrology target. The metrology target comprises specified filling elements introduced into identified continuous regions in a given target design, wherein parameters of the introduced filling elements are determined by a trade-off between a contrast requirement and an inaccuracy requirement which is associated via production with the identified continuous regions. The method includes the steps of identifying continuous regions in a target design, and introducing specified filling elements into the identified continuous regions, wherein parameters of the introduced filling elements are determined by a trade-off between a contrast requirement and an inaccuracy requirement which is associated via production with the identifying continuous regions. At least one of the identifying and the introducing can be carried out by at least one computer processor.

Metrology targets with filling elements that reduce inaccuracies and maintain contrast

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St. Yokne'am, Israel

Nuriel Amir