DEFECT INSPECTION DEVICE AND DEFECT INSPECTION METHOD

• US 20150369752A1
• Filed: 01/16/2014
• Published: 12/24/2015
• Est. Priority Date: 01/31/2013
• Status: Active Grant

• Current Assignee: Hitachi High-Tech Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi High-Technologies Corporation (Hitachi, Ltd.)
• Inventors: HONDA, Toshifumi, URANO, Takahiro, NISHIYAMA, Hidetoshi
• Granted Patent: US 9,778,206 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01N 2021/8887 based on image processing techniques
• CPC Class Codes: G01N 2021/9513 Liquid crystal panels
• CPC Class Codes: G01N 21/8851 Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges G01N21/8806 and G01N21/93 - G01N21/95692 take precedence; optical measurement of dimensions G01B11/00; optical scanning G02B26/10; image transformation G06T3/00; computerised image enhancement G06T5/00; image processing per se for flaw detection G06T7/0002
• 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

Abstract

In an defect inspection method and device, in order to detect a minute defect present on a surface of a sample with a high degree of sensitivity, a defect inspection method includes imaging the same region of a sample in a plurality of image acquisition conditions and acquiring a plurality of images, processing the plurality of acquired images and extracting a defect candidate, clipping a partial image including the extracted defect candidate and a neighboring image of the defect candidate from the acquired images based on position information of the extracted defect candidate, obtaining feature quantities of the defect candidates in the plurality of clipped partial images, associating the defect candidates that have the same coordinates on the sample and are detected in different image acquisition condition, extracting a defect from among the associated defect candidates in a multi-dimensional feature quantity space, and outputting information of the extracted defect.

Claims

1. A defect inspection method, comprising:

imaging with an image acquiring unit the same region of a sample in a plurality of image acquisition conditions and acquiring a plurality of images for the same region of the sample;

processing with a defect candidate extracting unit the plurality of acquired images of the sample and extracting a defect candidate in each of the plurality of images;

clipping with a partial image clipping unit a partial image including the extracted defect candidate and a neighboring image of the defect candidate from the plurality of acquired images based on position information of the extracted defect candidate;

obtaining with a feature quantity calculating unit feature quantities of the defect candidates in the plurality of clipped partial images;

associating with a defect candidate associating unit the defect candidates that have the same coordinates and are detected in conditions in which the image acquisition condition is different among the extracted defect candidate;

extracting with a defect extracting unit defect from among the associated defect candidates based on multi-dimensional feature quantity space data of feature quantities of the associated defect candidates; and

outputting with an output unit information of the extracted defect.

2. The defect inspection method according to claim 1,

wherein the acquiring of the plurality of images for the same region of the sample is performed multiple times while changing the image acquisition condition of the image acquiring unit, and in the outputting of the information of the defect, the defect candidates extracted from the images acquired multiple times while changing the image acquisition condition are associated and integrated by the defect extracting unit, and information of an integrated defect is output by the output unit.

3. The defect inspection method according to claim 1,

wherein the acquiring of the plurality of images for the same region of the sample is performed using a plurality of image acquiring units which are included in the image acquiring unit and differ in the image acquisition condition.

4. The defect inspection method according to claim 1,

wherein false information is removed by the feature quantity calculating unit based on coordinate information of the defect candidate from among the associated defect candidates, and multi-dimensional feature quantity space information is allocated to the defect candidate from which the false information has been removed.

5. The defect inspection method according to claim 1,

wherein the extracted defect is classified by the defect extracting unit, and information of the classified defect is output by the output unit.

6. A defect inspection method, comprising:

imaging with an image acquiring unit the same region of a sample in a plurality of image acquisition conditions and acquiring a plurality of images for the same region of the sample;

processing with a defect candidate extracting unit the plurality of acquired images and extracting a defect candidate in each of the plurality of images;

clipping with a partial image clipping unit a partial image including the extracted defect candidate and a neighboring image of the defect candidate from the plurality of acquired images based on position information of the extracted defect candidate;

performing with a control unit the acquiring of the plurality of images, the extracting of the defect candidate, and the clipping of the partial image multiple times while changing the plurality of image acquisition conditions; and

associating with a defect candidate associating unit the defect candidates having the same coordinates on the sample among the defect candidates included in the partial image clipped in the clipping of the partial image from the images obtained by imaging multiple times while changing the plurality of image acquisition conditions;

obtaining with a feature quantity calculating unit feature quantities of the associated defect candidates;

extracting with a defect extracting unit a defect from among the associated defect candidates based on multi-dimensional feature quantity space data of the feature quantities of the associated defect candidates; and

outputting with an output unit information of the extracted defect.

7. The defect inspection method according to claim 6,

wherein the acquiring of the plurality of images for the same region of the sample is performed using a plurality of image acquiring units which are included in the image acquiring unit and differ in the image acquisition condition.

8. The defect inspection method according to claim 6,

wherein false information is removed by the feature quantity calculating unit based on coordinate information of the defect candidate from among the associated defect candidates, and multi-dimensional feature quantity space information is allocated to the defect candidate from which the false information has been removed.

9. The defect inspection method according to claim 6,

wherein the extracted defect is classified by the defect extracting unit, and information of the classified defect is output by the output unit.

10. A defect inspection device, comprising:

an image acquiring unit that images the same region of a sample in a plurality of image acquisition conditions and acquires a plurality of images for the same region of the sample;

a defect candidate extracting unit that processes the plurality of acquired images of the sample acquired by the image acquiring unit and extracts a defect candidate in each of the plurality of images;

a partial image clipping unit that clips a partial image including the extracted defect candidate and a neighboring image of the defect candidate from the plurality of images acquired by the image acquiring unit based on position information of the defect candidate extracted by the defect candidate extracting unit;

a feature quantity calculating unit that obtains feature quantities of the defect candidates in the plurality of partial images clipped by the partial image clipping unit;

a defect candidate associating unit that associates the defect candidates that have the same coordinates and are detected in conditions in which the image acquisition condition is different among the defect candidate extracted by the defect candidate extracting unit;

a defect extracting unit that extracts a defect from among the defect candidates associated by the defect candidate associating unit based on multi-dimensional feature quantity space data of feature quantities of the associated defect candidates obtained by the feature quantity calculating unit; and

an output unit that outputs information of the defect extracted by the defect extracting unit.

11. The defect inspection device according to claim 10,

wherein the image acquiring unit performs the acquiring of the plurality of images for the same region of the sample multiple times while changing the image acquisition condition, the defect extracting unit associates and integrates the defect candidates extracted from the images acquired multiple times while changing the image acquisition condition through the image acquiring unit, and the output unit outputs information of a defect integrated by the defect extracting unit from the output unit.

12. The defect inspection device according to claim 11,

wherein the image acquiring unit includes a plurality of image acquiring units that differ in the image acquisition condition.

13. The defect inspection device according to claim 11,

wherein the feature quantity calculating unit removes false information based on coordinate information of the defect candidate from among the defect candidates associated by the defect candidate associating unit, and allocates multi-dimensional feature quantity space information to the defect candidate from which the false information has been removed.

14. The defect inspection device according to claim 11,

wherein the defect extracting unit further classifies the extracted defect, and the output unit outputs information of the classified defect.

15. A defect inspection device, comprising:

an image acquiring unit that images the same region of a sample in a plurality of image acquisition conditions and acquires a plurality of images for the same region of the sample;

a defect candidate extracting unit that processes the plurality of acquired images acquired by the image acquiring unit and extracts a defect candidate in each of the plurality of images;

a partial image clipping unit that clips a partial image including the extracted defect candidate and a neighboring image of the defect candidate from the plurality of images acquired by the image acquiring unit based on position information of the defect candidate extracted by the defect candidate extracting unit;

a control unit that controls the image acquiring unit, the defect candidate extracting unit, and the partial image clipping unit such that the acquiring of the plurality of images through the image acquiring unit, the extracting of the defect candidate through the defect candidate extracting unit, and the clipping of the partial image through the partial image clipping unit are performed multiple times while changing the plurality of image acquisition conditions;

a defect candidate associating unit that associates the defect candidates having the same coordinates on the sample among the defect candidates included in the partial image clipped by the partial image clipping unit from the images obtained by imaging multiple times while changing the plurality of image acquisition conditions of the image acquiring unit according to the control of the control unit;

a feature quantity calculating unit that obtains feature quantities of the defect candidates associated by the defect candidate associating unit;

a defect extracting unit that extracts a defect from among the defect candidates associated by the defect candidate associating unit based on multi-dimensional feature quantity space data of the feature quantities of the defect candidates obtained by the feature quantity calculating unit; and

an output unit that outputs information of the defect extracted by the defect extracting unit.

16. The defect inspection device according to claim 15,

wherein the image acquiring unit includes a plurality of image acquiring units that differ in the image acquisition condition.

17. The defect inspection device according to claim 15,

wherein the feature quantity calculating unit removes false information based on coordinate information of the defect candidate from among the defect candidates associated by the defect candidate associating unit, and allocates multi-dimensional feature quantity space information to the defect candidate from which the false information has been removed.

18. The defect inspection device according to claim 15,

wherein the defect extracting unit further classifies the extracted defect, and the output unit outputs information of the classified defect.