Defect classification/inspection system

• US 7,171,039 B2
• Filed: 08/16/2002
• Issued: 01/30/2007
• Est. Priority Date: 02/08/2002
• Status: Expired due to Fees

• Current Assignee: Sony Manufacturing Systems Corp. (Sony Group Corp.)
• Original Assignee: Sony Precision Technology, Inc. (Sony Group Corp.)
• Inventors: Kondo, Hiroshi, Saito, Yo, Okuyama, Masatsugu
• Primary Examiner(s): Mehta; Bhavesh M.
• Assistant Examiner(s): SHAH, UTPAL D
• Application Number:
  US10/222,431
• Publication Number:
  US 20030152276A1
• Time in Patent Office: 1,628 Days
• Field of Search: 382/149, 382/227, 382/305
• US Class Current: 382/149
• CPC Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/001 using an image reference approach

Abstract

An image of an inspection object is picked up by an image pickup unit, and a characteristics quantity of an image of a defect part extracted by a defect extracting unit is extracted and digitized by a characteristics extracting unit. A database preparing unit regroups defects having similar characteristics by a defect classification unit on the basis of the characteristics information digitized by the characteristics extracting unit with respect to defects belonging to a defect group selected and designated by an operator via a display/input unit, and prepares on a database memory a database in which the defects of the inspection object are hierarchically classified. A classification executing unit hierarchically classifies the defects of the inspection object with reference to the database provided by the database preparing unit on the basis of the digitized characteristics information extracted by the characteristics extracting unit from the image of the defect part of the inspection object extracted by the defect extracting unit. Thus, a defect classification/inspection system having high classification accuracy is provided.

Claims

1. A defect classification/inspection system comprising:

a defect extracting unit for picking up an image of an inspection object and comparing the image with a reference image having no defect, thereby extracting an image of a defect part;

a characteristics extracting unit for extracting and digitizing the characteristics quantity of the image of the defect part extracted by the defect extracting unit;

a database preparing unit including defect classifying means for grouping defects having similar characteristics on the basis of the characteristics information digitized by the characteristics extracting unit, classification code providing means for providing a classification code to the defects grouped by the defect classifying means, storage means for saving the characteristics information of the defects grouped by the defect classifying means together with the classification code provided by the classification code providing means as a database, and selecting/designating means for selecting and designating groups having mixed defects for which a database of a next hierarchical level is to be prepared, from the respective defect groups having the grouped defects and having the classification code provided thereto, the database preparing unit regrouping defects having similar characteristics by the defect classifying means on the basis of the characteristics information digitized by the characteristics extracting means with respect to the defects belonging to the mixed defect groups selected and designated by the selecting/designating means, and preparing a database in which the defects of the inspection object are hierarchically classified; and

a classification executing unit for hierarchically classifying the defects of the inspection object with reference to the database provided by the database preparing unit on the basis of the digitized characteristics information extracted by the characteristics extracting unit from the image of the defect part of the inspection object extracted by the defect extracting unit, wherein the classification executing unit includes a classification code determining unit for determining whether additional processing is needed based on the classification code.

2. The defect classification/inspection system as claimed in claim 1, wherein the defect extracting unit extracts the image of the defect part on the basis of a change of a repetitive pattern of the image obtained by picking up the image of the inspection object.

3. The defect classification/inspection system as claimed in claim 1, wherein the classification executing unit compares the digitized characteristics information extracted by the characteristics extracting unit with the database provided by the database preparing unit and provides a classification code, thereby hierarchically classifying the defect of the inspection object.

4. The defect classification/inspection system as claimed in claim 1, further comprising a display/input unit wherein the classification code is confirmed by an operator.

5. The defect classification/inspection system as claimed in claim 1, wherein the database in which the defects of the inspection object are hierarchically classified further comprises one or more databases for each hierarchical level.

6. The defect classification/inspection system as claimed in claim 1, wherein the defects are grouped in a predetermined number of groups.