Method and apparatus for inspecting pattern defects

• US 8,639,019 B2
• Filed: 09/12/2012
• Issued: 01/28/2014
• Est. Priority Date: 11/20/2003
• Status: Active Grant

• Current Assignee: Hitachi High-Tech Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi High-Technologies Corporation (Hitachi, Ltd.)
• Inventors: Sakai, Kaoru, Maeda, Shunji, Okabe, Takafumi
• Primary Examiner(s): Desire, Gregory M
• Application Number:
  US13/611,664
• Publication Number:
  US 20130004057A1
• Time in Patent Office: 503 Days
• Field of Search: 356/237.5, 356/625, 382/144, 382/149, 396/611, 704/36
• US Class Current: 382/149
• 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 21/95607 using a comparative method
• CPC Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/001 using an image reference approach

Abstract

A method of detecting a defect, including the steps of: illuminating step for illuminating a sample with a light; detecting step for detecting light from the specimen which is illuminated by the light and forming an image by processing the detected light; processing step for extracting a defect candidate by processing the image of the sample formed in the detecting step and determining an inspection condition by using images including the image of the sample acquired in the detecting step, a partial image including the extracted defect candidate and a reference image which corresponds to the partial image including the defect candidate.

Claims

1. A method of detecting a defect, comprising:

illuminating a sample with a light through an illumination optical system;

detecting light from the sample with an image detection section which is illuminated by the light, and forming an image by processing the detected light with an image editing section;

extracting a defect candidate with a defect candidate extraction unit by comparing the image of the sample formed in the detecting operation with a reference image to extract a difference in brightness between corresponding portions and determining an inspection condition of a defect detection unit by using images including the image of the sample acquired in the detecting operation, a partial image including the extracted defect candidate and the reference image which corresponds to the partial image including the defect candidate,

wherein the extracting and determining operations are effected, at least in part, by at least one of a hardware processor and circuitry.

2. The method of detecting a defect according to claim 1, wherein the image of the sample includes all of the images formed by processing the detected light in the detecting.

3. The method of detecting a defect according to claim 1, wherein the sample is a semiconductor wafer on which plural chips are formed, and wherein the image of the sample includes all of the images of the chips formed by processing the detected light in the detecting.

4. The method of detecting a defect according to claim 1, wherein in the processing, the inspection condition is determined by repeatedly detecting a defect by changing a defect detection condition or a defect classification condition using the images including the image of the sample, the partial image and the reference image.

5. An apparatus for detecting a defect, comprising:

an illuminating unit which illuminates a sample with a light;

a detecting unit which detects light from the sample which is illuminated by the light and forms an image by processing the detected light;

a processing unit which extracts a defect candidate by comparing the image of the sample formed by the detecting unit with a reference image to extract a different in brightness between corresponding portions and determines an inspection condition by using images including the image of the sample acquired by the detecting unit, a partial image including the extracted defect candidate and a reference image which corresponds to the partial image including the defect candidate.

6. The apparatus for detecting a defect according to claim 5, wherein the image of the sample formed by the detecting unit includes all of the images formed by processing the detected light in the detecting unit.

7. The apparatus for detecting a defect according to claim 5, wherein the sample is a semiconductor wafer on which plural chips are formed, and wherein the image of the sample formed by the detecting unit includes all of the images of the chips formed by processing the detected light in the detecting unit.

8. The apparatus for detecting a defect according to claim 5, wherein the processor determines the inspection condition by repeatedly detecting a defect by changing a defect detection condition or a defect classification condition using the images including the image of the sample, the partial image and the reference image.