DEFECT REVIEWING METHOD AND DEVICE

• US 20170082425A1
• Filed: 03/19/2015
• Published: 03/23/2017
• Est. Priority Date: 04/18/2014
• Status: Active Grant

• Current Assignee: Hitachi High-Tech Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi High-Technologies Corporation (Hitachi, Ltd.)
• Inventors: Minekawa, Yohei, Otani, Yuko, Takagi, Yuji
• Granted Patent: US 10,436,576 B2
• Time in Patent Office: Days
• CPC Class Codes: G01B 11/14 for measuring distance or clearance between spaced objects or spaced apertures G01B11/26 takes precedence; rangefinders G01C3/00
• CPC Class Codes: G01B 11/30 for measuring roughness or irregularity of surfaces
• CPC Class Codes: G01N 2021/8848 Polarisation of light
• CPC Class Codes: G01N 21/9501 Semiconductor wafers manufacturing processes per se of semiconductor devices implementing a measuring step H01L22/10
• CPC Class Codes: G01N 21/956 Inspecting patterns on the surface of objects contactless testing of electronic circuits G01R31/308; testing currency G07D; manufacturing processes per se of semiconductor devices implementing a measuring step H01L22/10
• CPC Class Codes: G01N 2223/30 Accessories, mechanical or electrical features
• CPC Class Codes: G01N 2223/646 flaws, defects
• CPC Class Codes: G01N 23/2204 Specimen supports therefor; Sample conveying means therefore
• CPC Class Codes: G01N 23/2251 using incident electron beams, e.g. scanning electron microscopy [SEM]
• CPC Class Codes: G02B 21/0092 Polarisation microscopes
• CPC Class Codes: G02B 21/10 affording dark-field illumination G02B21/14 and G02B21/125 take precedence
• CPC Class Codes: G02B 21/361 Optical details, e.g. image relay to the camera or image sensor G02B21/364 takes precedence; illumination details G02B21/06 and subgroups
• CPC Class Codes: G02B 21/367 providing an output produced by processing a plurality of individual source images, e.g. image tiling, montage, composite images, depth sectioning, image comparison
• CPC Class Codes: G02B 5/3083 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

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.

Claims

1-20. -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.