Optical near-field metrology
    1.
    发明授权

    公开(公告)号:US11815347B2

    公开(公告)日:2023-11-14

    申请号:US15599881

    申请日:2017-05-19

    摘要: Systems and methods are provided which utilize optical microcavity probes to map wafer topography by near-field interactions therebetween in a manner which complies with high volume metrology requirements. The optical microcavity probes detect features on a wafer by shifts in an interference signal between reference radiation and near-field interactions of radiation in the microcavities and wafer features, such as device features and metrology target features. Various illumination and detection configurations provide quick and sensitive signals which are used to enhance optical metrology measurements with respect to their accuracy and sensitivity. The optical microcavity probes may be scanned at a controlled height and position with respect to the wafer and provide information concerning the spatial relations between device and target features.

    UTILIZING OVERLAY MISREGISTRATION ERROR ESTIMATIONS IN IMAGING OVERLAY METROLOGY

    公开(公告)号:US20190122357A1

    公开(公告)日:2019-04-25

    申请号:US15739381

    申请日:2017-10-22

    IPC分类号: G06T7/00 G06T7/73 G03G15/00

    摘要: Systems and methods are provided, which calculate overlay misregistration error estimations from analyzed measurements of each ROI (region of interest) in at least one metrology imaging target, and incorporate the calculated overlay misregistration error estimations in a corresponding estimation of overlay misregistration. Disclosed embodiments provide a graduated and weighted analysis of target quality which may be integrated in a continuous manner into the metrology measurement processes, and moreover evaluates target quality in terms of overlay misregistration, which forms a common basis for evaluation of errors from different sources, such as characteristics of production steps, measurement parameters and target characteristics. Such common basis then enables any of combining various error sources to give a single number associated with measurement fidelity, analyzing various errors at wafer, lot and process levels, and/or to trade-off the resulting accuracy for throughput by reducing the number of measurements, in a controlled manner.

    Simultaneous capturing of overlay signals from multiple targets

    公开(公告)号:US10048132B2

    公开(公告)日:2018-08-14

    申请号:US15222503

    申请日:2016-07-28

    IPC分类号: G01J4/04 G01B11/27

    摘要: Metrology methods and systems are provided, in which the detected image is split at a field plane of the collection path of the metrology system's optical system into at least two pupil plane images. Optical elements such as prisms may be used to split the field plane images, and multiple targets or target cells may be measured simultaneously by spatially splitting the field plane and/or the illumination sources and/or by using two polarization types. The simultaneous capturing of multiple targets or target cells increases the throughput of the disclosed metrology systems.

    Optical Near-Field Metrology
    4.
    发明申请

    公开(公告)号:US20180087900A1

    公开(公告)日:2018-03-29

    申请号:US15599881

    申请日:2017-05-19

    摘要: Systems and methods are provided which utilize optical microcavity probes to map wafer topography by near-field interactions therebetween in a manner which complies with high volume metrology requirements. The optical microcavity probes detect features on a wafer by shifts in an interference signal between reference radiation and near-field interactions of radiation in the microcavities and wafer features, such as device features and metrology target features. Various illumination and detection configurations provide quick and sensitive signals which are used to enhance optical metrology measurements with respect to their accuracy and sensitivity. The optical microcavity probes may be scanned at a controlled height and position with respect to the wafer and provide information concerning the spatial relations between device and target features.

    Topographic Phase Control For Overlay Measurement

    公开(公告)号:US20170146915A1

    公开(公告)日:2017-05-25

    申请号:US15114175

    申请日:2016-05-19

    摘要: Metrology tools and methods are provided, which estimate the effect of topographic phases corresponding to different diffraction orders, which result from light scattering on periodic targets, and adjust the measurement conditions to improve measurement accuracy. In imaging, overlay error magnification may be reduced by choosing appropriate measurement conditions based on analysis of contrast function behavior, changing illumination conditions (reducing spectrum width and illumination NA), using polarizing targets and/or optical systems, using multiple defocusing positions etc. On-the-fly calibration of measurement results may be carried out in imaging or scatterometry using additional measurements or additional target cells.

    METROLOGY IMAGING TARGETS HAVING REFLECTION-SYMMETRIC PAIRS OF REFLECTION-ASYMMETRIC STRUCTURES
    6.
    发明申请
    METROLOGY IMAGING TARGETS HAVING REFLECTION-SYMMETRIC PAIRS OF REFLECTION-ASYMMETRIC STRUCTURES 审中-公开
    具有反射 - 非对称结构的反射对称对称的计量成像目标

    公开(公告)号:US20160084758A1

    公开(公告)日:2016-03-24

    申请号:US14928514

    申请日:2015-10-30

    IPC分类号: G01N21/47 G06F17/50

    摘要: Metrology targets, design files, and design and production methods thereof are provided. Metrology targets comprising at least one reflection-symmetric pair of reflection-asymmetric structures are disclosed. The structures may or may not be periodic, may comprise a plurality of unevenly-spaced target elements, which may or may not be segmented. The asymmetry may be with respect to target element segmentation or structural dimensions. Also, target design files and metrology measurements of the various metrology targets are disclosed.

    摘要翻译: 提供了计量目标,设计文件及其设计和制作方法。 公开了包括至少一个反射对称对的反射不对称结构的计量目标。 结构可以是或可以不是周期性的,可以包括多个不均匀间隔的目标元件,其可以被分割或者不被分割。 不对称性可能与目标元素分割或结构尺寸有关。 此外,还公开了各种度量目标的目标设计文件和度量测量。

    Topographic phase control for overlay measurement

    公开(公告)号:US11314173B2

    公开(公告)日:2022-04-26

    申请号:US16672483

    申请日:2019-11-03

    摘要: Metrology tools and methods are provided, which estimate the effect of topographic phases corresponding to different diffraction orders, which result from light scattering on periodic targets, and adjust the measurement conditions to improve measurement accuracy. In imaging, overlay error magnification may be reduced by choosing appropriate measurement conditions based on analysis of contrast function behavior, changing illumination conditions (reducing spectrum width and illumination NA), using polarizing targets and/or optical systems, using multiple defocusing positions etc. On-the-fly calibration of measurement results may be carried out in imaging or scatterometry using additional measurements or additional target cells.

    Off-axis illumination overlay measurement using two-diffracted orders imaging

    公开(公告)号:US11281111B2

    公开(公告)日:2022-03-22

    申请号:US16317603

    申请日:2018-12-14

    IPC分类号: G03F7/20 G01B11/27 G01B11/14

    摘要: Metrology methods and tools are provided, which enhance the accuracy of the measurements and enable simplification of the measurement process as well as improving the correspondence between the metrology targets and the semiconductor devices. Methods comprise illuminating the target in a Littrow configuration to yield a first measurement signal comprising a −1st diffraction order and a 0th diffraction order and a second measurement signal comprising a +1st distraction order and a 0th diffraction order, wherein the −1st diffraction order of the first measurement signal and the +1st diffraction order of the second measurement signal are diffracted at 180° to a direction of the illumination, performing a first measurement of the first measurement signal and a second measurement of the second measurement signal, and deriving metrology metric(s) therefrom. Optionally, a reflected 0th diffraction order may be split to yield components which interact with the −1st and +1st diffraction orders.

    Topographic Phase Control For Overlay Measurement

    公开(公告)号:US20210255551A1

    公开(公告)日:2021-08-19

    申请号:US17241006

    申请日:2021-04-26

    摘要: Metrology tools and methods are provided, which estimate the effect of topographic phases corresponding to different diffraction orders, which result from light scattering on periodic targets, and adjust the measurement conditions to improve measurement accuracy. In imaging, overlay error magnification may be reduced by choosing appropriate measurement conditions based on analysis of contrast function behavior, changing illumination conditions (reducing spectrum width and illumination NA), using polarizing targets and/or optical systems, using multiple defocusing positions etc. On-the-fly calibration of measurement results may be carried out in imaging or scatterometry using additional measurements or additional target cells.