Creating emission images of integrated circuits

• US 8,331,726 B2
• Filed: 06/29/2009
• Issued: 12/11/2012
• Est. Priority Date: 06/29/2009
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Stellari, Franco, Song, Peilin
• Primary Examiner(s): Mehta, Bhavesh
• Assistant Examiner(s): SHAH, UTPAL D
• Application Number:
  US12/493,686
• Publication Number:
  US 20100329586A1
• Time in Patent Office: 1,261 Days
• Field of Search: 382/284, 382/141, 382/278
• US Class Current: 382/284
• CPC Class Codes: G01R 31/303 of integrated circuits G01R31/305 - G01R31/315 take precedence
• CPC Class Codes: G06T 2200/32 involving image mosaicing
• CPC Class Codes: G06T 2207/10056 Microscopic image
• CPC Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/32 using correlation-based methods
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 23/58 Means for changing the camera field of view without moving the camera body, e.g. nutating or panning of optics or image sensors
• CPC Class Codes: H04N 5/2621 Cameras specially adapted for the electronic generation of special effects during image pickup, e.g. digital cameras, camcorders, video cameras having integrated special effects capability
• CPC Class Codes: H04N 5/2625 for obtaining an image which is composed of images from a temporal image sequence, e.g. for a stroboscopic effect sequence generated by event triggered capturing H04N7/188
• CPC Class Codes: H04N 5/2628 Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

A method, system and computer program product are disclosed for creating an image from a device. In one embodiment, the method comprises acquiring first and second images from the device, said first and second images having overlapping portions, and estimating said overlapping portions to obtain an approximate shift amount to align approximately said first and second images. This method further comprises analyzing the overlapping portions, using a defined cross-correlation algorithm, to calculate a precise shift amount to align the first and second images; and using said precise shift amount to join the first and second images together. In one embodiment, an optical system is used to acquire the images, a stage is used to move either the device or the optical system to acquire the first and second images, and the estimating includes using movement of the stage to estimate the overlapping areas.

Claims

1. A method of creating an image from a device, comprising:

defining a region of interest of the device;

separating said region of interest into a plurality of overlapping areas;

computing image acquisition locations for each of said overlapping areas;

using the computed image acquisition locations to acquire first and second images from first and second areas of the plurality of overlapping areas of the device, said first and second images having overlapping portions;

using the computed image acquisition locations for estimating said overlapping portions to obtain an approximate shift amount to align approximately said first and second images;

analyzing said overlapping portions, using a defined cross-correlation algorithm, to calculate a precise shift amount to align the first and second images; and

using said calculated precise shift amount to join the first and second images together to form a joined image.

2. The method according to claim 1, wherein the estimating includes estimating the sizes of the overlapping portions.

3. The method according to claim 1, wherein an optical system is used to acquire said images, and a stage is used to move either the device or the optical system in order to acquire said first and second images, and the estimating includes using the movement of the stage to estimate said overlapping areas.

4. The method according to claim 1, wherein the analyzing includes specifying corresponding locations in the overlapping portions, and applying said defined cross-correlation algorithm to said specified locations to calculate said precise shift amount.

5. The method according to claim 4, wherein an optical system including an array of pixels is used to acquire said first and second images, and said correspond locations are locations on said first and second images corresponding to specified ones of the pixels of said array.

6. The method according to claim 4, wherein the overlapping portions include corresponding regions of high emissions, and said corresponding locations in said overlapping portions are said corresponding regions of high emission.

7. The method according to claim 1, wherein the overlapping portions include corresponding regions of high emission, and said estimating includes using said corresponding regions of high emission to estimate said overlapping areas.

8. The method according to claim 1, further comprising processing said overlapping portions to reduce noise therein.

9. The method according to claim 1, wherein the separating said region of interest into a plurality of overlapping areas includes subdividing the region of interest into individual, partially overlapping images based on a field of view of the optical system and an overlap size.

10. A method of creating an image from a device, comprising:

acquiring first and second images from first and second areas of the device, said first and second images having overlapping portions;

estimating said overlapping portions to obtain an approximate shift amount to align approximately said first and second images;

analyzing said overlapping portions, using a defined cross-correlation algorithm, to calculate a precise shift amount to align the first and second images;

using said calculated precise shift amount to join the first and second images together to form a joined image; and

processing said overlapping portions to reduce noise therein, including identifying regions of high emission in one of the overlapping portions that do not have counterparts in the other of the overlapping portions, and removing at least some of said identified regions.

11. A system for acquiring and processing images from a device, comprising:

an optical system for collecting light from the device;

an imaging detector for measuring the intensity of the collected light;

a translation stage for moving the optical system or the device to enable the optical system to take multiple images of different areas of the device; and

a control unit for controlling movement of the translation stage, acquisition of the images, and processing of the images into a combined image; and

wherein;

the device includes a defined region of interest separated into a plurality of overlapping areas;

the control unit computes image acquisition locations for each of said overlapping areas, and uses the computed image acquisition locations to position the device relative to the optical system to take said multiple images;

said multiple images include first and second images of first and second areas of the plurality of overlapping areas of the device, said first and second images having overlapping portions; and

the control unit includes functionality for using the computed image acquisition locations for estimating said overlapping portions to obtain an approximate shift amount to align approximately said first and second images,

analyzing said overlapping portions, using a defined cross-correlation algorithm, to calculate a precise shift amount to align the first and second images, and

using said calculated precise shift amount to join the first and second images together to form a joined image.

12. The system according to claim 11, wherein said estimating includes estimating the overlapping portions based on movement of the translation stage.

13. The system according to claim 11, wherein the analyzing includes specifying corresponding locations in the overlapping portions, and applying said defined cross-correlation algorithm to said specified locations to calculate said precise shift amount.

14. The system according to claim 11, wherein:

said multitude of images are acquired in a given sequence, and the control unit includes functionality for,

each of at least selected ones of the multitude of images in the given sequence, determining an overlapping portion for a next image in the given sequence, determining a position for the translation stage to enable acquisition of said next image, and moving the translation stage to the determined position.

15. The system according to claim 11, wherein the determining the overlapping position includes determining the overlapping portion such that the overlapping portion has at least a defined minimum of light emission from the device.

16. An article of manufacture comprising:

at least one tangible computer readable device having computer readable program code logic tangibly embodied therein to execute machine instructions in one or more processing units for acquiring and processing images of a device in an image acquisition and processing system, the device including a define region of interest separated into a plurality of overlapping areas, and the image acquisition and processing systems including an optical system for collecting light from the device, and a translation stage to move the optical system or the device to enable the optical system to take multiple images of different areas of the device, said multiple images including first and second images of first and second areas of the plurality of overlapping areas of the device, said first and second images having overlapping portions, the computer readable program code logic, when executing, performing the following;

computing image acquisition locations for each of said overlapping areas;

using the computed image acquisition locations to acquire said first and second overlapping images;

controlling movement of the translation stage, acquisition of the images, and processing of the images into a combined image, including

using the computed image acquisition locations for estimating said overlapping portions to obtain an approximate shift amount to align approximately said first and second images, analyzing said overlapping portions, using a defined cross-correlation algorithm, to calculate a precise shift amount to align the first and second images, and

using said calculated precise shift amount to join the first and second images together to form a joined image.

17. The article of manufacture according to claim 16, wherein said estimating includes estimating the overlapping portions based on movement of the translation stage.

18. The article of manufacture according to claim 16, wherein the analyzing includes specifying corresponding locations in the overlapping portions, and applying said defined cross-correlation algorithm to said specified locations to calculate said precise shift amount.

19. The article of manufacture according to claim 16, wherein said multitude of images are acquired in a given sequence, and the method further comprises:

for each of at least selected ones of the multitude of images in the given sequence, determining an overlapping portion for a next image in the given sequence, determining a position for the translation stage to enable acquisition of said next image, and moving the translation stage to the determined position.

20. The article of manufacture according to claim 16, wherein the determining the overlapping position includes determining the overlapping portion such that the overlapping portion has at least a defined minimum of light emission from the device.

21. A method of creating an emission image of an area of an integrated circuit that is larger than a field of view of an optical system used for acquiring the image, the method comprising:

separating said area into a plurality of overlapping sections;

computing image acquisition locations for each of the overlapping sections;

acquiring first and second initial emission images of the plurality of overlapping sections of the integrated circuit, by using an optical system, wherein said first and second initial images have overlapping portions;

using the computed image acquisition locations for determining an approximate shift amount to obtain an approximate alignment of said first and second initial images;

processing at least parts of the first and second initial images, using a defined correlation algorithm, to determine a precise shift amount to align the first and second initial emission images; and

forming a composite image by using said precise shift amount to join together the first and second initial images, wherein the optical system has a field of view, and said composite image corresponds to the area of the integrated circuit that is larger than the field of view of the optical system.

22. The method according to claim 21, wherein:

the acquiring includes using relative movement between the integrated circuit and the optical system to acquire said first and second initial images; and

the determining includes using said relative movement to determine the approximate shift amount.

23. The method according to claim 21, wherein:

the acquiring includes acquiring a third initial emission image of a corresponding third section of the integrated circuit; and

said forming includes forming said composite image while acquiring said third initial emission image.

24. The method according to claim 21, wherein said correlation considers only one dimension of the first and second initial images.

25. The method according to claim 21, wherein the determining the approximate shift include estimating the sizes of the overlapping portions of the first and second initial images.