Pattern structure inspection device and inspection method

Patent metadata

Field	Value
Publication number	US-2019212276-A1
Application number	US-201716305982-A
Country	US
Kind code	A1
Filing date	Jun 1, 2017
Priority date	Jun 2, 2016
Publication date	Jul 11, 2019
Grant date	—

Abstract

According to an aspect of the present invention, there is provided a pattern structure inspection method including irradiating a wave from a wave source onto a sample including a pattern region in which a structure having a certain pattern is provided on a substrate, collecting speckle data generated due to multiple scattering of the wave in the pattern region, by using a data collector, and analyzing whether the structure of the pattern region has a defect, by comparing the collected speckle data to reference speckle data.

First claim

What is claimed is:

1 . A pattern structure inspection method comprising:
irradiating a wave from a wave source onto a sample comprising a pattern region in which a structure having a certain pattern is provided on a substrate; collecting speckle data generated due to multiple scattering of the wave in the pattern region, by using a data collector; and analyzing whether the structure of the pattern region has a defect, by comparing the collected speckle data to reference speckle data.

2 . The pattern structure inspection method of claim 1 , wherein the collecting of the speckle data is performed in an area between the sample and the data collector or in an internal area of the data collector.

3 . The pattern structure inspection method of claim 1 , wherein the collecting of the speckle data is performed in an area between a first surface comprising a first point spaced apart from a surface of the sample by a first distance, and a second surface comprising a second point spaced apart from the surface of the sample by a second distance greater than the first distance.

4 . The pattern structure inspection method of claim 1 , further comprising generating a three-dimensional (3D) speckle image by using a plurality of speckle signals detected by a plurality of data collectors, when the data collector comprises the plurality of data collectors.

5 . The pattern structure inspection method of claim 1 , wherein the collecting of the speckle data further comprises amplifying a number of times that the wave is multiple-scattered in the sample, by reflecting at least some waves multiple-scattered and emitted from the sample, back to the sample.

6 . The pattern structure inspection method of claim 1 , wherein the wave irradiated from the wave source comprises a laser beam.

7 . The pattern structure inspection method of claim 1 , wherein the sample has a structure in which a plurality of patterns are sequentially stacked on a substrate in a direction perpendicular to the substrate.

8 . The pattern structure inspection method of claim 1 , wherein the structure of the sample comprises a pattern region made of metal and a pattern region made of an insulator.

9 . A pattern structure inspection method for inspecting a pattern structure in a plurality of equal pattern regions spaced apart from each other by a certain distance and periodically repeated on a substrate, the method comprising:
performing a first operation for arbitrarily selecting a first pattern region among the plurality of pattern regions, irradiating a wave from a wave source onto the first pattern region, collecting speckle data generated due to multiple scattering of the wave in the first pattern region, and storing the collected data in a database (DB); performing a second operation for repeatedly performing the first operation on another at least one pattern region spaced apart from the first pattern region, and storing speckle data of the other pattern region in the DB; setting a criterion for determining a defect of each pattern region, by analyzing the speckle data collected in the first and second operations; and comparing the speckle data of each pattern region, which is stored in the DB, to the criterion, and determining whether the pattern region has a defect, based on a comparison result.

10 . A pattern structure inspection apparatus comprising:
a wave source for irradiating a wave onto a sample comprising a pattern region in which a structure having a certain pattern is provided on a substrate; a data collector for collecting speckle data generated due to multiple scattering of the irradiated wave by the sample; and a data analyzer for receiving and analyzing the speckle data collected by the data collector, and outputting an analysis result on a display, wherein the data collector collects the speckle data in an area between the sample and the data collector or in an internal area of the data collector.

11 . The pattern structure inspection apparatus of claim 10 , wherein the data collector collects the speckle data in a first area spaced apart from a surface of the sample by a certain distance.

12 . The pattern structure inspection apparatus of claim 11 , wherein the first area is located between a first surface comprising a first point spaced apart from the surface of the sample by a first distance, and a second surface comprising a second point spaced apart from the surface of the sample by a second distance greater than the first distance.

13 . The pattern structure inspection apparatus of claim 11 , wherein the first area is located between a first surface comprising a first point spaced apart from the surface of the sample by a first distance, and a second surface comprising a second point spaced apart from the surface of the sample by a second distance greater than the first distance.

14 . The pattern structure inspection apparatus of claim 10 , further comprising a three-dimensional (3D) image generator for generating a 3D speckle image by using a plurality of speckle signals detected by a plurality of data collectors, when the data collector comprises the plurality of data collectors, wherein the controller analyzes characteristics of the sample by using the 3D speckle image.

15 . The pattern structure inspection apparatus of claim 10 , further comprising a multiple scattering amplifier for amplifying a number of times that the wave is multiple-scattered in the sample, by reflecting at least some waves multiple-scattered and emitted from the sample, back to the sample.

16 . The pattern structure inspection apparatus of claim 15 , wherein the multiple scattering amplifier comprises:
a first multiple scattering amplifier located on an extension line passing through a center of the sample, to reflect at least some waves multiple-scattered and emitted from the sample, back to the sample; and a second multiple scattering amplifier located at an opposite side of the first multiple scattering amplifier with respect to the sample, to reflect at least some waves multiple-scattered and emitted from the sample, back to the sample.

17 . A pattern structure inspection apparatus comprising:
a sample holder accommodating a sample and a reference sample holder accommodating a reference sample; a wave source for irradiating a wave onto the sample and the reference sample; a data collector for collecting speckle data generated due to multiple scattering of the irradiated wave by each of the sample and the reference sample; and a data analyzer for receiving and analyzing the speckle data collected by the data collector, and outputting an analysis result on a display, wherein each of the sample and the reference sample comprises a pattern region in which a structure having a certain pattern is provided on a substrate.

18 . The pattern structure inspection apparatus of claim 17 , wherein the data collector collects the speckle data in an area between the sample and the data collector or in an internal area of the data collector.

19 . The pattern structure inspection apparatus of claim 17 , further comprising:
a multi-beam reflector for splitting the wave incident from the wave source, and providing the split waves along a plurality of paths; and a beam splitter located on the plurality of paths of the waves provided by the multi-beam reflector, to change paths of waves reflected and emitted from the sample and the reference sample, and provide the waves to the data collector.

Assignees

• The Wave Talk Inc
• Korea Advanced Inst Sci & Tech

Inventors

• Kim Young Dug
• Park Jongchan
• Park Yongkeun

Classifications

• G02B27/48

  Laser speckle optics · CPC title

• G02B26/12

  using multifaceted mirrors · CPC title

• G01N21/95607

  using a comparative method · CPC title

• G01N21/95684

  Patterns showing highly reflecting parts, e.g. metallic elements · CPC title

• G01N2021/95615

  with stored comparision signal · CPC title