Method of and apparatus for pattern inspection

• US 6,047,083 A
• Filed: 01/27/1998
• Issued: 04/04/2000
• Est. Priority Date: 01/29/1997
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Mizuno, Fumio
• Primary Examiner(s): Au, Amelia
• Assistant Examiner(s): Bali, Vikkram
• Application Number:
  US09/013,913
• Time in Patent Office: 798 Days
• Field of Search: 382/141, 382/149, 382/151, 382/150, 382/145, 382/144, 348/125, 348/126, 348/86, 348/87, 364/468.01, 364/468.02
• US Class Current: 382/141
• CPC Class Codes: G01N 23/2251 using incident electron beams, e.g. scanning electron microscopy [SEM]
• 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: 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
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A method and apparatus for pattern inspection forming an image of a specimen and inspecting a pattern formed on the specimen. This method includes the steps of storing a reference image corresponding to an image of the specimen into a memory, comparing the read out reference image from the memory with the image of the specimen, detecting differing portions between the reference image and image of the specimen as defects, and determining a probability of defects being or becoming a killer defect (i.e., a defect causing failure) of the specimen from other defects based on the detected differing portions.

Claims

1. A method for pattern inspection forming an image of a specimen and inspecting a pattern formed on the specimen, comprising the steps of:

storing a reference image corresponding to an image of said specimen into a memory;

comparing a read out reference image from said memory with said image of said specimen;

detecting differing portions between said reference image and image of said specimen as defects;

classifying said differing portions into a plurality of types with at least distances to an adjacent pattern measured with a minimum space used as a unit;

determining a probability of defect becoming a killer defect of said specimen based on said defects classified by type; and

displaying a result of said determination on a display screen,

wherein said differing portion and said reference image are overlapped and displayed on said display screen, and said differing portion is shifted to an edge of said adjoining pattern so that said differing portion comes into contact with said edge of said adjacent pattern, whereby said distance between said differing portion and said adjacent pattern is measured based on the distance of the movement.

2. A method for pattern inspection forming an image of a specimen and inspecting a pattern formed on the specimen, comprising the steps of:

storing a reference image corresponding to an image of said specimen into a memory;

comparing a read out reference image from said memory with said image of said specimen;

detecting differing portions between said reference image and image of said specimen as defects;

classifying said differing portions into a plurality of types with at least distances to an adjacent pattern measured with a minimum space used as a unit;

determining a probability of defect becoming a killer defect of said specimen based on said defects classified by type; and

displaying a result of said determination on a display screen,

wherein said differing portion and said reference image are overlapped and displayed with a predetermined scale on said display screen, whereby a distance between said differing portion and said adjoining pattern is measured by using said scale.

3. A method according to claim 2, wherein said scale is shaped like a straight line, a concurrence of concentric circuits which have an edge of the differing portion as the center of said circles, or a grid line.