Method for analyzing an object and a charged particle beam device for carrying out this method

Patent metadata

Field	Value
Publication number	US-9905394-B1
Application number	US-201715434132-A
Country	US
Kind code	B1
Filing date	Feb 16, 2017
Priority date	Feb 16, 2017
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

The system described herein analyzes an object using a charged particle beam device, such as an electron beam device and/or an ion beam device. The charged particle beam device is used to generate high resolution 3D data sets by sequentially removing material from the object, exposing surfaces of the object and generating images of the surfaces. When removing material from the object, an opening having sides is generated. Lamellas are generated using the sides and material characteristics of those lamellas are identified. Moreover, filtered data is generated for each pixel of images of the sides of the opening. The method uses the information with respect to the identified material characteristics, the images of the sides and the filtered data of those images to obtain information on the material characteristics for each pixel of each surface generated when sequentially removing material from the object.

First claim

The invention claimed is:

1. A method for analyzing an object using a charged particle beam device having a first charged particle beam generator for generating a first charged particle beam having first charged particles, a first objective lens for focusing the first charged particle beam onto the object, a second charged particle beam generator for generating a second charged particle beam having second charged particles, a second objective lens for focusing the second charged particle beam onto the object, a first detection unit and a second detection unit, the method comprising:
guiding the first charged particle beam over the object, removing material from the object using the first charged particle beam, exposing a first surface of the object when removing the material from the object, guiding the second charged particle beam over the first surface of the object, detecting first interaction particles using the first detection unit, the first interaction particles arising when the second charged particle beam impinges on the first surface, generating a first detection signal using the first detection unit and generating a first image of the first surface of the object using the first detection signal, the first image comprising first image pixels, each pixel of the first image pixels comprising first image data;
guiding the first charged particle beam over the object, removing material comprising the first surface from the object using the first charged particle beam, exposing a second surface of the object when removing the material from the object, guiding the second charged particle beam over the second surface of the object, detecting second interaction particles using the first detection unit, the second interaction particles arising when the second charged particle beam impinges on the second surface, generating a second detection signal using the first detection unit and generating a second image of the second surface of the object using the second detection signal, the second image comprising second image pixels, each pixel of the second image pixels comprising second image data, wherein an opening is generated when removing the material from the object so as to expose the first surface and the second surface of the object, wherein the opening comprises a first side comprising the second surface and a second side extending from the second surface of the object in a direction away from the second surface;
generating a first lamella comprising the first side of the opening having the second surface as an outer surface, and generating a second lamella comprising the second side of the opening;
guiding the second charged particle beam over the second side of the object, detecting third interaction particles using the first detection unit, the third interaction particles arising when the second charged particle beam impinges on the second side of the object, generating a third detection signal using the first detection unit and generating a third image of the second side of the object using the third detection signal, the third image comprising third image pixels, each pixel of the third image pixels comprising third image data;
analyzing the first lamella by identifying first material characteristics of the first lamella associated to each pixel of the second image pixels using at least one of: the first charged particle beam and the second charged particle beam, and detecting at least one of: fourth interaction particles and first interaction radiation using the second detection unit;
analyzing the second lamella by identifying second material characteristics of the second lamella associated to each pixel of the third image pixels using at least one of: the first charged particle beam and the second charged particle beam and detecting at least one of: fifth interaction particles and second interaction radiation using the second detection unit;
generating first filtered data for each pixel of the second image pixels using at least one first image filter for processing the second image data for each pixel of the second image pixels, and generating second filtered data for each pixel of the third image pixels using at least one second image filter for processing the third image data for each pixel of the third image pixels;
identifying data identical or similar to the first image data for each pixel of the first image pixels of the first image from among the following: the second image data of each pixel of the second image pixels, the third image data of each pixel of the third image pixels, the first filtered data for each pixel of the second image pixels and the second filtered data for each pixel of the third image pixels; and
assigning material characteristics to at least one pixel of the first image pixels of the first image, wherein the first material characteristics are assigned if at least one of: the identified second image data of a pixel of the second image pixels and the identified first filtered data for a pixel of the second image pixels is identical or similar to the first image data of the at least one pixel of the first image pixels and wherein the second material characteristics are assigned if at least one of: the identified third image data of a pixel of the third image pixels and the identified second filtered data for a pixel of the third image pixels is identical or similar to the first image data of the at least one pixel of the first image pixels.

2. The method according to claim 1 , further comprising:
generating a third lamella comprising a third side of the opening, the third side and the second side being arranged opposite to each other and the first side being arranged between the second side and the third side;
guiding the second charged particle beam over the third side of the object, detecting sixth interaction particles using the first detection unit, the sixth interaction particles arising when the second charged particle beam impinges on the third side of the object, generating a fourth detection signal using the first detection unit and generating a fourth image of the third side of the object using the fourth detection signal, the fourth image comprising fourth image pixels, each pixel of the fourth image pixels comprising fourth image data;
analyzing the third lamella by identifying third material characteristics of the third lamella associated to each pixel of the fourth image pixels using at least one of: the first charged particle beam and the second charged particle beam, and detecting at least one of: seventh interaction particles and third interaction radiation using the second detection unit;
generating third filtered data for each pixel of the fourth image pixels using at least one third image filter for processing the fourth image data for each pixel of the fourth image pixels;
the step of identifying data identical or similar to the first image data for each pixel of the first image pixels of the first image also comprising identifying from among the following: the fourth image data of each pixel of the fourth image pixels and the third filtered data for each pixel of the fourth image pixels; and
the step of assigning material characteristics to at least one pixel of the first image pixels of the first image comprising assigning the third material characteristics if at least one of: the identified fourth image data of a pixel of the fourth image pixels and the identified third filtered data for a pixel of the fourth image pixels is identical or similar to the first image data of the at least one pixel of the first image pixels.

3. The method according to claim 1 , wherein the step of identifying identical or similar data comprises comparing the first image data for each pixel of the first image pixels of the first image to at least one of: the second image data of each pixel of the second image pixels, the

Assignees

• Zeiss Carl Microscopy Gmbh

Inventors

• Bhattiprolu Sreenivas
• Lechner Lorenz

Classifications

• H01J37/28 Primary

  with scanning beams {(H01J37/268, H01J37/292, H01J37/2955 take precedence)} · CPC title

• H01J37/3053

  for evaporating or etching · CPC title

• H01J37/265

  Controlling the tube; circuit arrangements adapted to a particular application not otherwise provided, e.g. bright-field-dark-field illumination · CPC title

• H01J37/10

  Lenses · CPC title

• H01J37/244 Primary

  Detectors; Associated components or circuits therefor · CPC title