Scanning electron microscope and a method for pattern composite inspection using the same

• US 7,884,322 B2
• Filed: 10/30/2007
• Issued: 02/08/2011
• Est. Priority Date: 10/31/2006
• Status: Active Grant

• Current Assignee: Hitachi High-Tech Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi High-Technologies Corporation (Hitachi, Ltd.)
• Inventors: Sasajima, Fumihiro, Kato, Saori
• Primary Examiner(s): Kim; Robert
• Assistant Examiner(s): PURINTON, BROOKE J
• Application Number:
  US11/976,968
• Publication Number:
  US 20080099676A1
• Time in Patent Office: 1,197 Days
• Field of Search: 250/306, 250/307, 250/310, 382/147, 382/181, 382/190, 382/199, 382/218, 382/219, 700/110
• US Class Current: 250/306
• CPC Class Codes: G06T 2207/10061 from scanning electron microscope
• CPC Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/001 using an image reference approach
• CPC Class Codes: H01J 2237/2817 Pattern inspection

Abstract

A scanning electron microscope capable of performing alone the critical dimension measurement and the defect inspection is provided. The scanning electron microscope has a reference image storage unit for storing a reference image transcribing a reference pattern, an inspected image pick-up unit for picking up, on the basis of the reference image, an inspected image transcribing an inspection pattern which pattern-matches with the reference pattern, a critical dimension measuring unit for measuring critical dimensions of the inspection pattern by using the inspected image, and a defect inspection unit for performing an inspection of a defect inside or outside the inspection pattern by comparing the reference image with the inspected image.

Claims

1. A scanning electron microscope comprising:

a reference image storage unit for storing a reference image in which a reference pattern having an edge part is included;

an inspected image pick-up unit for picking up, on the basis of the reference image, an inspected image in which an inspection pattern which matches with said reference pattern is included, wherein the inspected image pick-up unit carries out a pattern matching between the inspected image and the reference image;

a critical dimension measuring unit for measuring critical dimensions of said inspection pattern by using said inspected image;

a non-inspection area set-up unit which sets a non-inspection area including an edge part of a pattern in the inspected image and the reference image on which the pattern matching has been carried out; and

a defect inspection unit for performing an inspection of a defect inside or outside said inspection pattern except the non-inspection area by comparing said reference image with said inspected image.

2. A scanning electron microscope according to claim 1, wherein said non-inspection area is a white band including the sidewalls of said reference pattern or said inspection pattern.

3. A scanning electron microscope according to claim 1, wherein said non-inspection area is an extracted area from which a deformed part in the inspection pattern, deformed from said reference pattern by a variation in production process of said reference pattern, is extracted.

4. A scanning electron microscope according to claim 1, wherein said non-inspection area set-up unit includes a display section for displaying said reference image or said inspected image, and a GUI which is used to arrange a patternized shape on said reference image or said inspected image displayed on said display section.

5. A scanning electron microscope according to claim 1, wherein said non-inspection area set-up unit includes an edge extraction section for extracting an edge part of said reference pattern or said inspection pattern, and an expansion section for expanding said edge part.

6. A scanning electron microscope according to claim 5, wherein said edge extraction section extracts said edge part on the basis of said reference image, inspected image, design data of said reference pattern or the result of said critical dimension measurement.

7. A scanning electron microscope according to claim 5, wherein said expansion section expands said edge part on the basis of a process variation tolerance value of production process of said inspection pattern.

8. A scanning electron microscope according to claim 1 further comprising a decision unit for deciding a state of formation of the inspection patterns from both the result of critical dimension measurement by said critical dimension measuring unit and the result of defect inspection of a defect inspection by said defect inspection unit.

9. A method for pattern composite inspection using a scanning electron microscope, comprising the steps of:

storing a reference image in which a reference pattern having an edge part is included, by means of the scanning electron microscope;

picking up, by means of said scanning electron microscope on the basis of said reference image, an inspected image in which an inspection pattern which pattern-matches with said reference pattern is included, wherein a pattern matching is carried out between the inspected image and the reference image;

measuring critical dimensions of said inspection pattern by using said inspected image;

setting a non-inspection area including an edge part of a pattern in the inspected image and the reference image on which the pattern matching has been carried out; and

inspecting a defect inside or outside said inspection pattern except the non-inspection area by comparing said reference image with said inspected image.