Defect reviewing method and device

Patent metadata

Field	Value
Publication number	US-2017082425-A1
Application number	US-201515126391-A
Country	US
Kind code	A1
Filing date	Mar 19, 2015
Priority date	Apr 18, 2014
Publication date	Mar 23, 2017
Grant date	—

Abstract

To review minute defects that were buried in roughness scattered light with an observation device provided with a dark-field microscope, a scanning electron microscope (SEM), and a control unit, the present invention configures the dark-field microscope by installing a filter for blocking a portion of the scattered light, an imaging lens for focusing the scattered light that has passed through the filter, and a detector for dividing the image of the scattered light focused by the imaging lens into the polarization directions converted by a wavelength plate and detecting the resulting images, and the control has a calculation unit for determining the position of a defect candidate detected by another inspection device using the plurality of images separated into polarization directions and detected by the detector.

First claim

The invention claimed is:

1 - 20 . (canceled)

21 . A defect reviewing device comprising:
a dark-field microscope that identify a position of a defect on a sample that is detected by another inspection device; a scanning electron microscope (SEM) that reviews the defect on the sample the position of which is identified by the dark-field microscope; a table that carries the sample and is capable of moving between the dark-field microscope and the SEM; and a control unit that controls the dark-field microscope, the SEM, and the table; wherein the dark-field microscope includes an illumination light source that illuminates the sample with illumination light, an objective lens that collects scattered light generated from the sample illuminated with the illumination light from the illumination light source, a wavelength plate that converts the polarization directions of the scattered light from the sample, the scattered light being collected by the objective lens, a filter that blocks part of the scattered light transmitted through the wavelength plate and transmits the remaining portion of the scattered light, an imaging lens that forms an image of the scattered light transmitted through the filter, and a detector that detects the image of the scattered light by separating the image into the polarization directions converted by the wavelength plate, the image being formed by the imaging lens; and wherein the control unit includes a computation unit that determines the position of a defect candidate detected by the other inspection device by using a plurality of images that are detected by the detector after separation into the polarization directions.

22 . The defect reviewing device according to claim 21 , wherein the detector includes two-dimensionally arrayed pixels; and wherein neighboring pixels of the two-dimensionally arrayed pixels detect light beams polarized in different directions.

23 . The defect reviewing device according to claim 21 , wherein the distribution wavelength plate converts radially polarized light and azimuthally polarized light to different beams of linearly polarized light.

24 . The defect reviewing device according to claim 21 , wherein the computation unit calculates a defect candidate by performing a threshold value process on the brightness values of images in different polarization directions, the images being detected by the detector.

25 . A defect reviewing device comprising:
a dark-field microscope that identify a position of a defect on a sample that is detected by another inspection device; a scanning electron microscope (SEM) that reviews the defect on the sample the position of which is identified by the dark-field microscope; a table that carries the sample and is capable of moving between the dark-field microscope and the SEM; and a control unit that controls the dark-field microscope, the SEM, and the table; wherein the dark-field microscope includes an illumination light source that illuminates the sample with illumination light, an objective lens that collects scattered light generated from the sample that is illuminated with the illumination light from the illumination light source, a wavelength plate that converts the polarization directions of the scattered light from the sample, the scattered light being collected by the objective lens, a polarization beam splitter that is rotatable about the optical axis of the objective lens, an imaging lens that forms an image of the scattered light transmitted through the polarization beam splitter, and a detector that detects the image of the scattered light that is formed by the imaging lens; and wherein the control unit includes a computation unit that identifies a position of a defect candidate detected by the other inspection device by using a plurality of images that are detected with the detector by rotating the polarization beam splitter about the optical axis.

26 . The defect reviewing device according to claim 25 , wherein the distribution wavelength plate converts radially polarized light and azimuthally polarized light to different beams of linearly polarized light.

27 . The defect reviewing device according to claim 25 , wherein the computation unit calculates a defect candidate by performing a threshold value process on the brightness values of images in different polarization directions, the images being detected by the detector.

28 . A defect reviewing device comprising:
a dark-field microscope that identifies a position of a defect on a sample that is detected by another inspection device; a scanning electron microscope (SEM) that reviews the defect on the sample the position of which is identified by the dark-field microscope; a table that carries the sample and is capable of moving between the dark-field microscope and the SEM; and a control unit that controls the dark-field microscope, the SEM, and the table; wherein the dark-field microscope includes an illumination light source that illuminates the sample with illumination light, an objective lens that collects scattered light generated from the sample that is illuminated with the illumination light from the illumination light source, a filter that includes a light-shielding region for shielding part of the scattered light from the sample and is capable of changing the light-shielding region, the scattered light being collected by the objective lens, an imaging lens that forms an image of the scattered light transmitted through a portion other than the light-shielding region of the filter, and a detector that detects the image of the scattered light that is formed by the imaging lens; and wherein the control unit includes a computation unit that identifies a position of a defect candidate detected by the other inspection device by using a plurality of images detected with the detector while changing the light-shielding region of the filter.

29 . The defect reviewing device according to claim 28 , wherein the computation unit identifying the position of the defect in accordance with the amount of change in the brightness values of a plurality of images detected with the detector while changing the light-shielding region of the filter.

30 . The defect reviewing device according to claim 28 , wherein the computation unit identifies a position of a defect in accordance with the attenuation amount of the brightness value, the attenuation amount being indicative of the amount of change in the brightness value.

Assignees

• Hitachi High Tech Corp

Inventors

• Minekawa Yohei
• Otani Yuko
• Takagi Yuji

Classifications

• G01B11/14 Primary

  for measuring distance or clearance between spaced objects or spaced apertures (G01B11/26 takes precedence; rangefinders G01C3/00) · CPC title

• G02B5/3083

  Birefringent or phase retarding elements (G02B5/3008, G02B5/3016 take precedence; systems for polarisation control G02B27/286; manufacturing phase modulating patterns by lithographic processes G03F7/001) · CPC title

• G01N2021/8848

  Polarisation of light · CPC title

• G01N23/2251

  using incident electron beams, e.g. scanning electron microscopy [SEM] · CPC title

• G02B21/10

  affording dark-field illumination (G02B21/14 {and G02B21/125} take precedence) · CPC title