公开(公告)号：US20180301385A1

公开(公告)日：2018-10-18

申请号：US15576811

申请日：2017-10-24

Applicant: KLA-Tencor Corporation

Inventor： Naomi Ittah ,  Nadav Gutman ,  Eran Amit ,  Vincent Immer ,  Einat Peled

IPC: H01L21/66 ,  G01B11/14 ,  G01B11/26 ,  H01L21/67

Abstract: A method of overlay control in silicon wafer manufacturing comprises firstly locating a target comprising a diffraction grating on a wafer layer; and then measuring the alignment of patterns in successive layers of the wafer. The location of the target may be done by the pupil camera rather than a vision camera by scanning the target to obtain pupil images at different locations along a first axis. The pupil images may comprise a first order diffraction pattern for each location. A measurement of signal intensity in the first order diffraction pattern is then obtained for each location. The variation of signal intensity with location along each axis is then analyzed to calculate the location of a feature in the target.

公开(公告)号：US11060845B2

公开(公告)日：2021-07-13

申请号：US16665759

申请日：2019-10-28

Applicant: KLA-Tencor Corporation

Inventor： Eran Amit ,  Barry Loevsky ,  Andrew Hill ,  Amnon Manassen ,  Nuriel Amir ,  Vladimir Levinski ,  Roie Volkovich

IPC: G01B11/06 ,  G01B11/27 ,  G01N21/95 ,  G01N21/956 ,  G06F30/392 ,  G06F30/398 ,  H01L21/66 ,  G01N21/88

Abstract: 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.

公开(公告)号：US11054752B2

公开(公告)日：2021-07-06

申请号：US16102424

申请日：2018-08-13

Applicant: KLA-Tencor Corporation

Inventor： Eran Amit ,  Daniel Kandel ,  Dror Alumot ,  Amit Shaked ,  Liran Yerushalmi

IPC: G03F7/20 ,  H01L21/66 ,  H01L27/02 ,  H01L27/092

Abstract: An overlay metrology system includes one or more processors coupled to an illumination source to direct illumination to a sample and a detector to capture diffracted orders of radiation from the sample. The system may generate overlay sensitivity calibration parameters based on differential measurements of a calibration target including two overlay target cells on the sample, where first-layer target elements and second-layer target elements of the overlay target cells are distributed with a common pitch along a measurement direction and are misregistered with a selected offset value in opposite directions. The system may further determine overlay measurements based on differential measurements of additional overlay target cells with two wavelengths, where first-layer target elements and second-layer target elements of the additional overlay target cells are distributed with the common pitch and are formed to overlap symmetrically. The system may further adjust the overlay measurements with the overlay sensitivity calibration parameters.

公开(公告)号：US10699969B2

公开(公告)日：2020-06-30

申请号：US15774025

申请日：2018-04-05

Applicant: KLA-TENCOR CORPORATION

Inventor： Einat Peled ,  Eran Amit ,  Alexander Svizher ,  Yuval Lamhot ,  Noga Sella ,  Wei-Te Cheng

IPC: H01L21/66 ,  H01L21/67 ,  G03F7/20

Abstract: Methods applicable in metrology modules and tools are provided, which enable adjusting metrology measurement parameters with respect to process variation, without re-initiating metrology recipe setup. Methods comprise, during an initial metrology recipe setup, recording a metrology process window and deriving baseline information therefrom, and during operation, quantifying the process variation with respect to the baseline information, and adjusting the metrology measurement parameters within the metrology process window with respect to the quantified process variation. The quick adjustment of metrology parameters avoids metrology-related process delays and releases prior art bottlenecks related thereto. Models of effects of various process variation factors on the metrology measurements may be used to enhance the derivation of required metrology tuning and enable their application with minimal delays to the production process.

公开(公告)号：US10685165B2

公开(公告)日：2020-06-16

申请号：US15082152

申请日：2016-03-28

Applicant: KLA-Tencor Corporation

Inventor： Daniel Kandel ,  Mark D. Smith ,  Mark Wagner ,  Eran Amit ,  Myungjun Lee

IPC: G01R31/14 ,  G06F30/398 ,  H01L21/66 ,  G01N21/93 ,  G01N21/956 ,  G06F119/18

Abstract: Metrology methods are provided, which comprise identifying overlay critical patterns in a device design, the overlay critical patterns having an overlay sensitivity to process variation above a specified threshold that depends on design specifications; and using metrology targets that correspond to the identified overlay critical patterns. Alternatively or complementarily, metrology methods comprise identifying yield critical patterns according to a corresponding process window narrowing due to specified process variation, wherein the narrowing is defined by a dependency of edge placement errors (EPEs) of the patterns on process parameters. Corresponding targets and measurements are provided.

公开(公告)号：US10571811B2

公开(公告)日：2020-02-25

申请号：US15159009

申请日：2016-05-19

Applicant: KLA-Tencor Corporation

Inventor： Eran Amit ,  Daniel Kandel ,  Dror Alumot ,  Amit Shaked ,  Liran Yerushalmi

IPC: G03F7/20 ,  H01L21/66 ,  H01L27/02 ,  H01L27/092

Abstract: Metrology methods and targets are provided, that expand metrological procedures beyond current technologies into multi-layered targets, quasi-periodic targets and device-like targets, without having to introduce offsets along the critical direction of the device design. Several models are disclosed for deriving metrology data such as overlays from multi-layered target and corresponding configurations of targets are provided to enable such measurements. Quasi-periodic targets which are based on device patterns are shown to improve the similarity between target and device designs, and the filling of the surroundings of targets and target elements with patterns which are based on device patterns improve process compatibility. Offsets are introduced only in non-critical direction and/or sensitivity is calibrated to enable, together with the solutions for multi-layer measurements and quasi-periodic target measurements, direct device optical metrology measurements.

公开(公告)号：US10551749B2

公开(公告)日：2020-02-04

申请号：US15442111

申请日：2017-02-24

Applicant: KLA-Tencor Corporation

Inventor： Vladimir Levinski ,  Amnon Manassen ,  Eran Amit ,  Nuriel Amir ,  Liran Yerushalmi ,  Amit Shaked

IPC: G03F7/20

Abstract: 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 Moiré 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 Moiré patterns.

公开(公告)号：US10473460B2

公开(公告)日：2019-11-12

申请号：US15979336

申请日：2018-05-14

Applicant: KLA-Tencor Corporation

Inventor： Nadav Gutman ,  Eran Amit ,  Stefan Eyring ,  Hari Pathangi ,  Frank Laske ,  Ulrich Pohlmann ,  Thomas Heidrich

IPC: H01J37/26 ,  G01B15/00

Abstract: An overlay metrology system includes a particle-beam metrology tool to scan a particle beam across an overlay target on a sample including a first-layer target element and a second-layer target element. The overlay metrology system may further include a controller to receive a scan signal from the particle-beam metrology tool, determine symmetry measurements for the scan signal with respect to symmetry metrics, and generate an overlay measurement between the first layer and the second layer based on the symmetry measurements in which an asymmetry of the scan signal is indicative of a misalignment of the second-layer target element with respect to the first-layer target element and a value of the overlay measurement is based on the symmetry measurements.

公开(公告)号：US10458777B2

公开(公告)日：2019-10-29

申请号：US14949444

申请日：2015-11-23

Applicant: KLA-TENCOR CORPORATION

Inventor： Eran Amit ,  Barry Loevsky ,  Andrew Hill ,  Amnon Manassen ,  Nuriel Amir ,  Vladimir Levinski ,  Roie Volkovich

IPC: G01B11/06 ,  G01B11/27 ,  G01N21/95 ,  G01N21/956 ,  G06F17/50 ,  H01L21/66 ,  G01N21/88

Abstract: 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.

公开(公告)号：US20190250521A1

公开(公告)日：2019-08-15

申请号：US16398175

申请日：2019-04-29

Applicant: KLA-Tencor Corporation

Inventor： Eran Amit ,  Raviv YOHANAN

IPC: G03F7/20 ,  G01N21/95 ,  G01N21/47

CPC classification number: G03F7/70633 ,  G01N21/47 ,  G01N21/4785 ,  G01N21/9501 ,  G01N2201/02 ,  G01N2201/12 ,  G03F7/70683

Abstract: Metrology targets, design files, and design and production methods thereof are provided. The targets comprise two or more parallel periodic structures at respective layers, wherein a predetermined offset is introduced between the periodic structures, for example, opposite offsets at different parts of a target. Quality metrics are designed to estimate the unintentional overlay from measurements of a same metrology parameter by two or more alternative measurement algorithms. Target parameters are configured to enable both imaging and scatterometry measurements and enhance the metrology measurements by the use of both methods on the same targets. Imaging and scatterometry target parts may share elements or have common element dimensions. Imaging and scatterometry target parts may be combined into a single target area or may be integrated into a hybrid target using a specified geometric arrangement.