HIGH-SENSITIVITY OPTICAL SCANNING USING MEMORY INTEGRATION

• US 20070012865A1
• Filed: 09/18/2006
• Published: 01/18/2007
• Est. Priority Date: 06/22/2001
• Status: Active Grant

• Current Assignee: Orbotech Limited (KLA Corporation)
• Original Assignee: Orbotech Limited (KLA Corporation)
• Inventors: MALINOVICH, Yacov, KATZIR, Yigal, GUR-ARIE, Itay
• Granted Patent: US 7,417,243 B2
• Time in Patent Office: Days
• US Class Current: 250/208.100
• 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 21/8901 Optical details; Scanning details per se G02B
• 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
• CPC Class Codes: H01L 27/14645 Colour imagers
• CPC Class Codes: H04N 25/46 by combining or binning pixels
• CPC Class Codes: H04N 25/768 for time delay and integration [TDI]
• CPC Class Codes: H04N 25/772 comprising A/D, V/T, V/F, I/T or I/F converters
• CPC Class Codes: H04N 3/155 Control of the image-sensor operation, e.g. image processing within the image-sensor

Abstract

An inspection system includes a CMOS integrated circuit having integrally formed thereon an at least two dimensional array of photosensors and providing an inspection output representing an object to be inspected. A defect analyzer is operative to receive the inspection output and to provide a defect report.

Claims

1. An inspection system comprising:

a light source providing non-continuous illumination;

a two dimensional array of photosensors operative to acquire at a frame rate a plurality of at least partially overlapping two dimensional image frames of an object to be inspected, wherein said non-continuous illumination and said frame rate are generally synchronized; and

a defect analyzer operative to receive said two dimensional image frames, to combine overlapping portions of said two dimensional image frames to generate a representation of said object to be inspected, and to provide a report of defects on said object to be inspected based on an inspection of said representation.

2. The inspection system claimed in claim 1, wherein said two dimensional array of photosensors are disposed on a CMOS integrated circuit.

3. The inspection system claimed in claim 1, wherein said two dimensional array of photosensors provides a plurality of digital images, each digital image being defined by pixels.

4. The inspection system claimed in claim 3, wherein said representation of said object comprises a digital representation defined by pixels, said representation being formed by combining corresponding pixels from overlapping portions of different two dimensional image frames.

5. The inspection system image system claimed in claim 1, wherein each two dimensional image frame in said plurality of two dimensional image frames at least partially overlaps another two dimensional image frame in said plurality of two dimensional image frames by at least a single row of pixels.

6. The inspection system claimed in claim 5, wherein each two dimensional image frame in said plurality of two dimensional image frames substantially overlaps another two dimensional image frame in said plurality of image frames.

7. The inspection system claimed in claim 6, wherein each two dimensional image frame in said plurality of two dimensional image frames substantially overlaps another two dimensional image frame in said plurality of two dimensional image but does not overlap a single row of pixels.

8. A method for inspecting an object, comprising:

illuminating an object to be inspected with non-continuous illumination;

acquiring at a frame rate a plurality of at least partially overlapping two dimensional image frames of said object to be inspected, wherein said non-continuous illuminating and said acquiring at a frame rate are generally synchronized; and

generating a representation of said object to be inspected by combining overlapping portions of said two dimensional image frames; and

reporting defects on said object to be inspected based on an inspection of said representation;

9. The method claimed in claim 8, acquiring is performed using a two dimensional array of photosensors are disposed on a CMOS integrated circuit.

10. The method claimed in claim 8, wherein said acquiring two dimensional image frames comprises acquiring a plurality of digital images, each digital image being defined by pixels.

11. The method claimed in claim 10, wherein said generating a representation of said object comprises generating a digital representation defined by pixels, said representation being generated by combining corresponding pixels from overlapping portions of different two dimensional image frames.

12. The method claimed in claim 8, wherein each two dimensional image frame in said plurality of two dimensional image frames at least partially overlaps another two dimensional image frame in said plurality of two dimensional image frames by at least a single row of pixels.

13. The method claimed in claim 12, wherein each two dimensional image frame in said plurality of two dimensional image frames substantially overlaps another two dimensional image frame in said plurality of image frames.

14. The method claimed in claim 13, wherein each two dimensional image frame in said plurality of two dimensional image frames substantially overlaps another two dimensional image frame in said plurality of two dimensional image but does not overlap a single row of pixels.