System for inspecting and reviewing a sample

• US 10,177,048 B2
• Filed: 03/04/2015
• Issued: 01/08/2019
• Est. Priority Date: 03/04/2015
• Status: Active Grant

• Current Assignee: Applied Materials Israel Limited (Applied Materials Incorporated)
• Original Assignee: Applied Materials Israel Limited (Applied Materials Incorporated)
• Inventors: Frosien, Juergen, Levin, Jacob, Krivts (Krayvitz), Igor, Uziel, Yoram, Golberg, Boris
• Primary Examiner(s): Stoffa, Wyatt
• Application Number:
  US14/639,003
• Publication Number:
  US 20160260642A1
• Time in Patent Office: 1,406 Days
• CPC Class Codes: H01J 2237/2817 Pattern inspection
• CPC Class Codes: H01J 37/226 Optical arrangements for illuminating the object; optical arrangements for collecting light from the object
• CPC Class Codes: H01J 37/228 whereby illumination or light collection take place in the same area of the discharge
• CPC Class Codes: H01J 37/265 Controlling the tube; circuit arrangements adapted to a particular application not otherwise provided, e.g. bright-field-dark-field illumination
• CPC Class Codes: H01J 37/28 with scanning beams H01J37/268, H01J37/292, H01J37/2955 take precedence
• CPC Class Codes: H01J 37/292 using scanning ray
• CPC Class Codes: H01L 22/12 for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions electrical measurement of diffusions H01L22/14

Abstract

A system for inspecting and reviewing a sample, the system may include a chamber that is arranged to receive the sample and to maintain vacuum within the chamber during at least a scan period; an inspection unit; a review unit; and a mechanical stage for moving the sample, according to a scan pattern and during the scan period, in relation to the inspection unit and the review unit while a spatial relationship between the inspection unit and the review unit remains unchanged; wherein the inspection unit is arranged to detect, during the scan period, multiple suspected defects of the sample; and wherein the review unit is arranged to (a) receive, during the scan period, information about the multiple suspected defects; and (b) locate, during the scan period and in response to the information about the multiple suspected defects, at least one actual defect.

Claims

1. A system for inspecting and reviewing a sample, the system comprising:

a controller;

a chamber that is arranged to receive the sample and to maintain vacuum within the chamber during at least a scan period;

an inspection unit communicatively coupled to the controller, the inspection unit arranged to detect, during the scan period, multiple suspected defects of the sample in the chamber;

a review unit communicatively coupled to the controller, the review unit arranged to;

(i) receive, during the scan period, information about the multiple suspected defects detected by the inspection unit, and (ii) locate, during the scan period and in response to the information about the multiple suspected defects, at least one actual defect of the sample in the chamber; and

a mechanical stage communicatively coupled to and controlled by the controller to move the sample in the chamber, according to a scan pattern and during the scan period, in relation to the inspection unit and the review unit,

wherein a spatial relationship between the inspection unit and the review unit remains unchanged during the scan period;

wherein the scan pattern includes a plurality of parallel scan lines;

wherein the review unit includes one or more columns, and wherein the inspection unit and at least one of the one or more columns are arranged along a line that is nonparallel to the plurality of parallel scan lines; and

wherein the one or more columns are operable to review, while the sample is moved by the mechanical stage according to the scan pattern, the suspected defects detected by the inspection unit according to a review scheme dynamically determined by the controller based on the scan pattern and information about the suspected defects detected by the inspection unit.

2. The system according to claim 1 wherein the inspection unit comprises optics that are arranged to scan the sample during the scan period with a photon beam and a column from the one or more columns of the review unit is arranged to scan the sample during the scan period with a charged particle beam.

3. The system according to claim 2 wherein the column is arranged to scan a location of a certain suspected defect out of the multiple suspected defects by deflecting the charged particle beam and at least partially countering the scan pattern.

4. The system according to claim 2 wherein at least a portion of the column and at least a portion of the optics are positioned within the chamber.

5. The system according to claim 1 wherein the inspection unit and the review unit are arranged to scan the sample during the scan period with charged particle beams.

6. The system according to claim 1 wherein each column of the one or more columns is arranged to scan the sample during the scan period with a charged particle beam.

7. The system according to claim 6 wherein the inspection unit comprises optics that are arranged to scan the sample during the scan period with a photon beam.

8. The system according to claim 1 wherein the system further comprises an interface that is arranged to output information related to actual defects.

9. The system according to claim 1 wherein:

the inspection unit comprises an objective lens, an illumination module, a dark field deflector, a beam splitter and a light sensor;

the chamber comprises a window and an opening;

the objective lens is positioned within the opening;

the illumination module, the beam splitter and light sensor are positioned outside the chamber;

the dark field deflector is positioned within the chamber;

the illumination module is arranged to;

(i) direct a light beam towards the beam splitter when operating in a bright field operational mode, and (ii) direct a light beam through the window and towards the dark field deflector when operating in a dark field operational mode; and

the objective lens is arranged to;

(i) receive a light beam from the beam splitter and direct the light beam towards the sample, and (ii) direct light emitted from the sample through the beam splitter and towards a light sensor.

10. The system according to claim 1 wherein a distance between an optical axis of the inspection unit and an optical axis of the review unit does not exceed a diameter of the sample.

11. The system according to claim 1 wherein a distance between an optical axis of the inspection unit and an optical axis of the review unit exceeds a diameter of the sample.

12. The system according to claim 1 wherein a distance between an optical axis of the inspection unit and an optical axis of the review unit does not exceed 40 centimeters.

13. The system according to claim 1 wherein the inspection unit is arranged to scan the sample in compliance with the scan pattern and the review unit is arranged to scan areas of the sample that comprise at least a part of the multiple suspected defects while deviating from the scan pattern.

14. The system according to claim 1 wherein the review unit comprises at least one scanning electron microscope (SEM) column that is positioned with respect to the inspection unit such that the at least one SEM column is operable to review the sample at locations of interest on a scanning line which was previously scanned by the inspection unit.

15. The system according to claim 1, wherein the review unit comprises two columns, the inspection unit and the two columns positioned on three vertices of a triangle.

16. The system according to claim 1, wherein the review scheme is further determined based on arrangement of the one or more columns.

17. A method for inspecting and reviewing a sample, the method comprising:

receiving, by a chamber, the sample;

maintaining vacuum within the chamber during at least a scan period;

moving, by a mechanical stage communicatively coupled to and controlled by a controller, the sample in the chamber, according to a scan pattern and during the scan period, in relation to an inspection unit and a review unit, wherein a spatial relationship between the inspection unit and the review unit remains unchanged during the scan period, and wherein the scan pattern includes a plurality of parallel scan lines;

detecting, by the inspection unit and during the scan period, multiple suspected defects of the sample in the chamber;

receiving, by the review unit and during the scan period, information about the multiple suspected defects; and

locating at least one actual defect of the sample in the chamber, by the review unit and the controller, during the scan period, and in response to the information about the multiple suspected defects, wherein the review unit includes one or more columns, and wherein the inspection unit and at least one of the one or more columns are arranged along a line that is nonparallel to the plurality of parallel scan lines such that the one or more columns are operable to review, while the sample is moved by the mechanical stage according to the scan pattern, the suspected defects detected by the inspection unit according to a review scheme dynamically determined by the controller based on the scan pattern, information about the suspected defects detected by the inspection unit, and arrangement of the one or more columns.

18. The method according to claim 17 further comprising:

outputting information related to the at least one actual defect.

19. A system for inspecting and reviewing a sample, the system comprising:

a controller;

a chamber defining a substrate processing zone;

a vacuum system operatively coupled to the chamber to maintain vacuum within the chamber during a scan period;

a mechanical stage communicatively coupled to the controller and configured to support and move the sample within the substrate processing zone of the chamber during the scan period according to a scan pattern controlled by the controller, the scan pattern including a plurality of parallel scan lines;

an inspection unit comprising optics arranged to scan the sample during the scan period with a photon beam, the inspection unit coupled to the chamber, communicatively coupled to the controller, and arranged to detect, during the scan period, suspected defects of the sample; and

a review unit coupled to the chamber such that a spatial relationship between the inspection unit and the review unit remains unchanged during the scan period, the review unit communicatively coupled to the controller to receive information about the suspected defects detected by the inspection unit, the review unit comprising a scanning electron microscope (SEM) column and operable to review the suspected defects detected by the inspection unit according to a review scheme dynamically determined by the controller based on the scan pattern and information about the suspected defects detected by the inspection unit while the sample is moved by the mechanical stage according to the scan pattern, wherein the SEM column and the inspection unit are arranged along a line that is nonparallel to the plurality of parallel scan lines.