公开(公告)号：US20170059493A1

公开(公告)日：2017-03-02

申请号：US15215341

申请日：2016-07-20

Applicant: FEI Company

Inventor： Andrew Kingston ,  Shane Latham ,  Adrian Sheppard ,  Glenn Myers ,  Benoit Recur ,  Heyang Li

IPC: G01N23/04 ,  H01J37/26

CPC classification number: G01N23/046 ,  G01N2223/401 ,  G01N2223/418 ,  G01N2223/419 ,  G06T11/006 ,  H01J37/26

Abstract: A method of investigating a specimen using a tomographic imaging apparatus comprising: A specimen holder, for holding the specimen; A source, for producing a beam of radiation that can be directed at the specimen; A detector, for detecting a flux of radiation transmitted through the specimen from the source; A stage apparatus, for producing relative motion of the source with respect to the specimen, so as to allow the source and detector to image the specimen along a series of different viewing axes; A processing apparatus, for performing a mathematical reconstruction step whereby output from the detector is compiled into a tomographic image of at least part of the specimen, wherein said reconstruction step is performed in multiple iterations, which comprise the following steps: (i) Using a Back Projection technique to produce an initial tomogram from a set of initial images; (ii) Subjecting said initial tomogram to a mathematical filtering operation, thereby producing an adjusted tomogram; (iii) Using a Forward Projection technique on said adjusted tomogram to dissociate it into a set of calculated images; (iv) Repeating steps (i)-(iii) until said calculated images satisfy an acceptance criterion.

公开(公告)号：US11428828B2

公开(公告)日：2022-08-30

申请号：US16284496

申请日：2019-02-25

Applicant: FEI Company

Inventor： Andrew Kingston ,  Shane Latham ,  Adrian Sheppard ,  Glenn Myers ,  Benoit Recur ,  Heyang Li ,  Trond Karsten Varslot

IPC: G06T11/00 ,  G01T1/29 ,  G01N23/046 ,  G01N23/2204 ,  H01J37/22

Abstract: A method of investigating a specimen using a tomographic imaging apparatus comprising: A specimen holder, for holding the specimen; A source, for producing a beam of radiation that can be directed at the specimen; A detector, for detecting a flux of radiation transmitted through the specimen from the source; A stage apparatus, for producing relative motion of the source with respect to the specimen, so as to allow the source and detector to image the specimen along a series of different viewing axes; A processing apparatus, for assembling output from the detector into a tomographic image of at least part of the specimen, which method comprises the following steps: Considering a virtual reference surface that surrounds the specimen and is substantially centered thereon; Considering an incoming point of intersection of each of said viewing axes with this reference surface, thereby generating a set of such intersection points corresponding to said series of viewing axes; Choosing discrete viewing axes in said series so as to cause said set to comprise a two-dimensional lattice of points located areally on said reference surface in a substantially uniform distribution.

公开(公告)号：US20190187306A1

公开(公告)日：2019-06-20

申请号：US16284496

申请日：2019-02-25

Applicant: FEI Company

Inventor： Andrew Kingston ,  Shane Latham ,  Adrian Sheppard ,  Glenn Myers ,  Benoit Recur ,  Heyang Li ,  Trond Karsten Varslot

IPC: G01T1/29 ,  G06T11/00 ,  H01J37/22 ,  G01N23/2204 ,  G01N23/046

CPC classification number: G01T1/2985 ,  G01N23/046 ,  G01N23/2204 ,  G06T11/005 ,  G06T2211/436 ,  H01J37/222 ,  H01J2237/2807

Abstract: A method of investigating a specimen using a tomographic imaging apparatus comprising: A specimen holder, for holding the specimen; A source, for producing a beam of radiation that can be directed at the specimen; A detector, for detecting a flux of radiation transmitted through the specimen from the source; A stage apparatus, for producing relative motion of the source with respect to the specimen, so as to allow the source and detector to image the specimen along a series of different viewing axes; A processing apparatus, for assembling output from the detector into a tomographic image of at least part of the specimen, which method comprises the following steps: Considering a virtual reference surface that surrounds the specimen and is substantially centered thereon; Considering an incoming point of intersection of each of said viewing axes with this reference surface, thereby generating a set of such intersection points corresponding to said series of viewing axes; Choosing discrete viewing axes in said series so as to cause said set to comprise a two-dimensional lattice of points located areally on said reference surface in a substantially uniform distribution.

公开(公告)号：US10254419B2

公开(公告)日：2019-04-09

申请号：US15237309

申请日：2016-08-15

Applicant: FEI Company

Inventor： Andrew Kingston ,  Shane Latham ,  Adrian Sheppard ,  Glenn Myers ,  Benoit Recur ,  Heyang Li ,  Trond Karsten Varslot

IPC: G01T1/29 ,  G06T11/00 ,  G01N23/046 ,  G01N23/2204 ,  H01J37/22

Abstract: A method of investigating a specimen using a tomographic imaging apparatus using a stage for producing relative motion of a source with respect to a specimen, so as to allow the source and a detector to image the specimen along a series of different viewing axes and a processing apparatus for assembling a tomographic image of at least part of the specimen. The investigation is carried out by considering a virtual reference surface that surrounds the specimen and is substantially centered thereon, considering an incoming point of intersection of each of said viewing axes with this reference surface, thereby generating a set of such intersection points corresponding to the series of viewing axes, choosing discrete viewing axes in the series so as to cause the set to comprise a two-dimensional lattice of points located areally on the reference surface in a substantially uniform distribution.

公开(公告)号：US10152785B2

公开(公告)日：2018-12-11

申请号：US15221524

申请日：2016-07-27

Applicant: FEI Company

Inventor： Andrew Kingston ,  Shane Latham ,  Adrian Sheppard ,  Benoit Recur ,  Trond Karsten Varslot

IPC: G06K9/00 ,  G06T7/00 ,  G06T11/00

Abstract: A method for investigating a specimen using a tomographic imaging apparatus, comprising acquiring a set of input images of the specimen taken at a corresponding set of source positions that are intended to lie on an ideal locus but are instead caused by positioning errors to lie on a distorted locus, using the images to construct an initial tomographic image, dissociating the initial tomographic image into a set of reference images referenced to said ideal locus, comparing the given input images to the corresponding reference images, calculating a set of transformations necessary to map the input images onto the reference images, and using the set of transformations to construct a modified tomographic image.