公开(公告)号：US11698251B2

公开(公告)日：2023-07-11

申请号：US17137840

申请日：2020-12-30

Applicant: KLA Corporation

Inventor： Andrei V. Shchegrov ,  Nadav Gutman ,  Alexander Kuznetsov ,  Antonio Arion Gellineau

IPC: G01B15/00 ,  G03F7/00 ,  H01L21/66 ,  G01B15/02 ,  H01L21/027 ,  H10B10/00

CPC classification number: G01B15/00 ,  G01B15/02 ,  G03F7/70516 ,  G03F7/70633 ,  H01L22/12 ,  H01L22/20 ,  G01B2210/56 ,  H01L21/0276 ,  H10B10/12

Abstract: Methods and systems for performing overlay and edge placement errors based on Soft X-Ray (SXR) scatterometry measurement data are presented herein. Short wavelength SXR radiation focused over a small illumination spot size enables measurement of design rule targets or in-die active device structures. In some embodiments, SXR scatterometry measurements are performed with SXR radiation having energy in a range from 10 to 5,000 electronvolts. As a result, measurements at SXR wavelengths permit target design at process design rules that closely represents actual device overlay. In some embodiments, SXR scatterometry measurements of overlay and shape parameters are performed simultaneously from the same metrology target to enable accurate measurement of Edge Placement Errors. In another aspect, overlay of aperiodic device structures is estimated based on SXR measurements of design rule targets by calibrating the SXR measurements to reference measurements of the actual device target.

公开(公告)号：US11604420B2

公开(公告)日：2023-03-14

申请号：US17488010

申请日：2021-09-28

Applicant: KLA Corporation

Inventor： Stilian Pandev ,  Min-Yeong Moon ,  Andrei V. Shchegrov ,  Jonathan Madsen ,  Dimitry Sanko ,  Liran Yerushalmi ,  Alexander Kuznetsov ,  Mahendra Dubey

IPC: G03F7/20

Abstract: A self-calibrating overlay metrology system may receive device overlay data from device targets on a sample, determine preliminary device overlay measurements for the device targets including device-scale features using an overlay recipe with the device overlay data as inputs, receive assist overlay data from sets of assist targets on the sample including device-scale features, where a particular set of assist targets includes one or more target pairs formed with two overlay targets having programmed overlay offsets of a selected value with opposite signs along a particular measurement direction. The system may further determine self-calibrating assist overlay measurements for the sets of assist targets based on the assist overlay data, where the self-calibrating assist overlay measurements are linearly proportional to overlay on the sample, and generate corrected overlay measurements for the device targets by adjusting the preliminary device overlay measurements based on the self-calibrating assist overlay measurements.

公开(公告)号：US11604063B2

公开(公告)日：2023-03-14

申请号：US17473742

申请日：2021-09-13

Applicant: KLA Corporation

Inventor： Stilian Pandev ,  Min-Yeong Moon ,  Andrei V. Shchegrov ,  Jonathan Madsen ,  Dimitry Sanko ,  Liran Yerushalmi ,  Alexander Kuznetsov ,  Mahendra Dubey

IPC: G01B21/24

Abstract: An overlay metrology system may receive overlay data for in-die overlay targets within various fields on a skew training sample from one or more overlay metrology tools, wherein the in-die overlay targets within the fields have a range programmed overlay offsets, wherein the fields are fabricated with a range of programmed skew offsets. The system may further generate asymmetric target signals for the in-die overlay targets using an asymmetric function providing a value of zero when physical overlay is zero and a sign indicative of a direction of physical overlay. The system may further generate corrected overlay offsets for the in-die overlay targets on the asymmetric target signals, generate self-calibrated overlay offsets for the in-die overlay targets based on the programmed overlay offsets and the corrected overlay offsets, generate a trained overlay recipe, and generate overlay measurements for in-die overlay targets on additional samples using the trained overlay recipe.

公开(公告)号：US20240142948A1

公开(公告)日：2024-05-02

申请号：US17978844

申请日：2022-11-01

Applicant: KLA Corporation

Inventor： Alexander Kuznetsov ,  Xiaoyue Luo

IPC: G05B19/418 ,  G06T7/00

CPC classification number: G05B19/41815 ,  G05B19/4184 ,  G05B19/41865 ,  G06T7/0004

Abstract: Methods and systems for evaluating individual semiconductor metrology tool productivity based on both individual tool productivity metrics and fleet productivity metrics are described herein. Productivity metrics associated with each individual tool are combined with productivity metrics associated with a fleet of tools to identify problematic tools quickly and with fewer false positives. In particular, tool productivity results are obtained much more quickly in situations where productivity is driven by low frequency events. Values of one or more accuracy metrics indicative of a confidence in the ranking of individual tools among the fleet of measurement tools are estimated. In addition, a probability of a future failure event associated with an individual tool of the fleet of measurement tools is predicted based on a difference between a predicted probability distribution of the failure event and an actual, observed distribution of the failure event.

公开(公告)号：US20230128610A1

公开(公告)日：2023-04-27

申请号：US17510307

申请日：2021-10-25

Applicant: KLA CORPORATION

Inventor： Liran Yerushalmi ,  Alexander Kuznetsov

IPC: H01L21/67 ,  G06N3/08 ,  G06N3/04 ,  G06F17/18

Abstract: Two machine learning modules or models are used to generate a recipe. A first machine learning module determines a set of recipes based on measured signals. The second machine learning module analyzes the set of recipes based on a cost function to determine a final recipe. The second machine learning module also can determine settings if the set of recipes fail evaluation using the cost function.

公开(公告)号：US20220412734A1

公开(公告)日：2022-12-29

申请号：US17473742

申请日：2021-09-13

Applicant: KLA Corporation

Inventor： Stilian Pandev ,  Min-Yeong Moon ,  Andrei V. Shchegrov ,  Jonathan Madsen ,  Dimitry Sanko ,  Liran Yerushalmi ,  Alexander Kuznetsov ,  Mahendra Dubey

IPC: G01B21/24

Abstract: An overlay metrology system may receive overlay data for in-die overlay targets within various fields on a skew training sample from one or more overlay metrology tools, wherein the in-die overlay targets within the fields have a range programmed overlay offsets, wherein the fields are fabricated with a range of programmed skew offsets. The system may further generate asymmetric target signals for the in-die overlay targets using an asymmetric function providing a value of zero when physical overlay is zero and a sign indicative of a direction of physical overlay. The system may further generate corrected overlay offsets for the in-die overlay targets on the asymmetric target signals, generate self-calibrated overlay offsets for the in-die overlay targets based on the programmed overlay offsets and the corrected overlay offsets, generate a trained overlay recipe, and generate overlay measurements for in-die overlay targets on additional samples using the trained overlay recipe.

公开(公告)号：US20220349752A1

公开(公告)日：2022-11-03

申请号：US17856660

申请日：2022-07-01

Applicant: KLA Corporation

Inventor： Tianhan Wang ,  Aaron Rosenberg ,  Dawei Hu ,  Alexander Kuznetsov ,  Manh Dang Nguyen ,  Stilian Pandev ,  John Lesoine ,  Qiang Zhao ,  Liequan Lee ,  Houssam Chouaib ,  Ming Di ,  Torsten R. Kaack ,  Andrei V. Shchegrov ,  Zhengquan Tan

IPC: G01J3/18 ,  G01J3/28 ,  G01N21/55 ,  G01N21/956 ,  G01N21/21 ,  G01N21/25 ,  G01N21/88 ,  G01N21/84

Abstract: A spectroscopic metrology system includes a spectroscopic metrology tool and a controller. The controller generates a model of a multilayer grating including two or more layers, the model including geometric parameters indicative of a geometry of a test layer of the multilayer grating and dispersion parameters indicative of a dispersion of the test layer. The controller further receives a spectroscopic signal of a fabricated multilayer grating corresponding to the modeled multilayer grating from the spectroscopic metrology tool. The controller further determines values of the one or more parameters of the modeled multilayer grating providing a simulated spectroscopic signal corresponding to the measured spectroscopic signal within a selected tolerance. The controller further predicts a bandgap of the test layer of the fabricated multilayer grating based on the determined values of the one or more parameters of the test layer of the fabricated structure.

公开(公告)号：US11460418B2

公开(公告)日：2022-10-04

申请号：US16551616

申请日：2019-08-26

Applicant: KLA Corporation

Inventor： Alexander Kuznetsov ,  Chao Chang

IPC: G01N23/20 ,  G01N23/20008 ,  G01N23/205 ,  H01L21/66

Abstract: Methods and systems for measuring structural and material characteristics of semiconductor structures based on wavelength resolved, soft x-ray reflectometry (WR-SXR) at multiple diffraction orders are presented. WR-SXR measurements are simultaneous, high throughput measurements over multiple diffraction orders with broad spectral width. The availability of wavelength resolved signal information at each of the multiple diffraction orders improves measurement accuracy and throughput. Each non-zero diffraction order includes multiple measurement points, each different measurement point associated with a different wavelength. In some embodiments, WR-SXR measurements are performed with x-ray radiation energy in a range of 10-5,000 electron volts at grazing angles of incidence in a range of 1-45 degrees. In some embodiments, the illumination beam is controlled to have relatively high divergence in one direction and relatively low divergence in a second direction, orthogonal to the first direction. In some embodiments, multiple detectors are employed, each detecting different diffraction orders.

公开(公告)号：US11880142B2

公开(公告)日：2024-01-23

申请号：US18118420

申请日：2023-03-07

Applicant: KLA Corporation

Inventor： Stilian Pandev ,  Min-Yeong Moon ,  Andrei V. Shchegrov ,  Jonathan Madsen ,  Dimitry Sanko ,  Liran Yerushalmi ,  Alexander Kuznetsov ,  Mahendra Dubey

IPC: G03F7/00

CPC classification number: G03F7/70633 ,  G03F7/70516 ,  G03F7/70775

Abstract: A self-calibrating overlay metrology system may receive device overlay data for a device targets on a sample from an overlay metrology tool, determine preliminary device overlay measurements for the device targets including device-scale features using an overlay recipe with the device overlay data as inputs, receive assist overlay data for one or more assist targets on the sample including device-scale features from the overlay metrology tool, where at least one of the one or more assist targets has a programmed overlay offset of a selected value along a particular measurement direction, determine self-calibrating assist overlay measurements for the one or more assist targets based on the assist overlay data, where the self-calibrating assist overlay measurements are linearly proportional to overlay on the sample, and generate corrected overlay measurements for the device targets by adjusting the preliminary device overlay measurements based on the self-calibrating assist overlay measurements.

公开(公告)号：US20230221656A1

公开(公告)日：2023-07-13

申请号：US18118420

申请日：2023-03-07

Applicant: KLA Corporation

Inventor： Stilian Pandev ,  Min-Yeong Moon ,  Andrei V. Shchegrov ,  Jonathan Madsen ,  Dimitry Sanko ,  Liran Yerushalmi ,  Alexander Kuznetsov ,  Mahendra Dubey

IPC: G03F7/20

CPC classification number: G03F7/70633 ,  G03F7/70516 ,  G03F7/70775

Abstract: A self-calibrating overlay metrology system may receive device overlay data for a device targets on a sample from an overlay metrology tool, determine preliminary device overlay measurements for the device targets including device-scale features using an overlay recipe with the device overlay data as inputs, receive assist overlay data for one or more assist targets on the sample including device-scale features from the overlay metrology tool, where at least one of the one or more assist targets has a programmed overlay offset of a selected value along a particular measurement direction, determine self-calibrating assist overlay measurements for the one or more assist targets based on the assist overlay data, where the self-calibrating assist overlay measurements are linearly proportional to overlay on the sample, and generate corrected overlay measurements for the device targets by adjusting the preliminary device overlay measurements based on the self-calibrating assist overlay measurements.