Charged particle beam device

Patent metadata

Field	Value
Publication number	US-9786468-B2
Application number	US-201414762621-A
Country	US
Kind code	B2
Filing date	Feb 5, 2014
Priority date	Feb 26, 2013
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

An object of the invention is to provide a charged particle beam apparatus capable of performing high-precision measurement even on a pattern in which a width of edges is narrow and inherent peaks of the edges cannot be easily detected. In order to achieve the above object, there is proposed a charged particle beam apparatus including an opening portion forming member having a passage opening of a charged particle beam and a detector for detecting charged particles emitted from a sample or charged particles generated by causing the charged particles to collide with the opening portion forming member, the charged particle beam apparatus including: a deflector for deflecting the charged particles emitted from the sample; and a control device for controlling the deflector, the control device performing pattern measurement with the use of a first detected signal in which a signal of one edge is emphasized relatively more than a signal of another edge among a plurality of edges on the sample and a second detected signal in which the signal of the another edge is emphasized relatively more than the signal of the one edge among the plurality of edges.

First claim

The invention claimed is:

1. A charged particle beam apparatus comprising:
a first detector including:
a first opening portion forming member having a first passage opening through which a charged particle beam emitted from a charged particle source passes and a detection part that detects charged particles generated by collision of the charged particles emitted from the sample to the first opening portion forming member, or
a detection part having the first passage opening through which the charged particle beam emitted from the charged particle source passes and detecting the charged particles emitted from the sample;

a second detector including:
a second opening portion forming member having a second passage opening through which the charged particle beam emitted from the charged particle source passes and a detection part that detects charged particles generated by collision of the charged particles passing through the first passage opening to the second opening portion member, or
a detection part having the second passage opening through which the charged particle beam emitted from the charged particle source passes and detecting the charged particles which pass through the first opening;

a deflector that deflects the charged particles emitted from the sample by irradiating the sample with the charged particle beam; and
a control device configured to
control the deflector to detect a first detected signal in which a signal of one edge is emphasized relatively more than a signal of another edge among a plurality of edges on the sample based on an output of the first detector, and detect a second detected signal in which the signal of the another edge is emphasized relatively more than the signal of the one edge among the plurality of edges based on an output of the second detector,
generate a first signal waveform from the first detected signal and a second signal waveform from the second detected signal, and
perform pattern measurement using the first signal waveform and the second signal waveform.

2. The charged particle beam apparatus according to claim 1 , wherein
the control device is configured to control the deflector so that a detected signal amount of the one edge by the detector is increased.

3. The charged particle beam apparatus according to claim 1 , wherein
the control device is configured to control the deflector so that the charged particles emitted from the sample are deflected in a direction orthogonal to an extension direction of a pattern formed on the sample.

4. The charged particle beam apparatus according to claim 3 , wherein
the control device is configured to read the extension direction of the pattern from design data and reflects the extension direction in a deflection condition of secondary electrons.

5. The charged particle beam apparatus according to claim 3 , wherein
a direction of a track of secondary electrons to be deflected is a linear direction connecting two points to determine a shape difference in an observation pattern.

6. The charged particle beam apparatus according to claim 1 , wherein
the control device is configured to synthesize two or more SEM images in which different azimuth angle components are detected and perform length measurement of a size of a pattern on the basis of edges of patterns extracted from the respective images.

7. The charged particle beam apparatus according to claim 1 , wherein
the control device is configured to synthesize two or more SEM images in which different azimuth angle components are detected and predict an original shape.

8. The charged particle beam apparatus according to claim 1 , wherein
the controller is configured to determine a distance of a track of secondary electrons to be deflected based on a range of secondary electrons reaching the opening portion forming member.

9. The charged particle beam apparatus according to claim 1 , wherein
before secondary electrons are deflected and detected, the control device is configured to determine a reach position of the secondary electrons and cause the reach position to correspond to the center of a field of view at the time of observation by scanning a surface with an electron beam.

10. The charged particle beam apparatus according to claim 1 , wherein
the control device is configured to determine a direction and a distance of secondary electrons to be deflected based on a reach position of the secondary electrons toward a stop and a spread range of the secondary electrons in the stop.

11. A charged particle beam apparatus including comprising:
a detector including:
a first opening portion forming member having a first passage opening through which a charged particle beam emitted from a charged particle source passes and a detection part that detects charged particles generated by collision of the charged particles emitted from the sample to the first opening portion forming member, or
a detection part having the first passage opening through which the charged particle beam emitted from the charged particle source passes and detecting the charged particles emitted from the sample;

a deflector that deflects the charged particles emitted from the sample by irradiating the sample with the charged particle beam; and
a control device that controls the deflector, the control device being configured to switch a deflection condition of the deflector between a first deflection condition and a second deflection condition to
obtain a first detected signal by controlling the deflector under the first deflection condition in which the charged particle beam is deflected such that the charged particles emitted from one edge among a plurality of edges on the sample are directed to the first opening portion forming member or the detection part while the charged particles emitted from another edge among the plurality of edges are directed to the passage opening,
obtain a second detected signal by controlling the deflector under the second deflection condition in which the charged particle beam is deflected such that the charged particles emitted from the another edge are directed to the first opening portion forming member or the detection part while the charged particles emitted from the one edge are directed to the passage opening, and
perform pattern measurement using the first detected signal and the second detected signal.

12. A charged particle beam apparatus comprising:
a detector including:
a first opening portion forming member having a first passage opening through which a charged particle beam emitted from a charged particle source passes and a detection part detecting charged particles generated by collision of charged particles emitted from the sample to the first opening portion forming member, or
a detection part having the first passage opening through which the charged particle beam emitted from the charged particle source passes and detecting the charged particles emitted from the sample;

a second opening portion forming member that is different from the detector and is arranged between the detector and the sample;
a deflector that deflects the charged particles emitted from the sample by irradiating the sample with the charged particle beam; and
a control device configured to switch a deflection condition of the deflector between a first deflection condition and a second deflection condition to:
control the deflector to detect a first detected signal under the first deflection condition in which the charged particle beam is deflected such that the charged particles emitted from one edge among a plurality of edges on the sample are directed to the first opening portion forming member or the detect

Assignees

• Hitachi High Tech Corp

Inventors

• Yokosuka Toshiyuki
• Lee Chahn
• Kazumi Hideyuki

Classifications

• H01J37/1474 Primary

  Scanning means · CPC title

• H01J2237/15

  Means for deflecting or directing discharge · CPC title

• H01J37/147

  Arrangements for directing or deflecting the discharge along a desired path ({H01J37/045 take precedence;} lenses H01J37/10) · CPC title

• H01J2237/2806

  Secondary charged particle · CPC title

• H01J37/244

  Detectors; Associated components or circuits therefor · CPC title