Continuous light inspection

Patent metadata

Field	Value
Publication number	US-10497092-B2
Application number	US-201615347013-A
Country	US
Kind code	B2
Filing date	Nov 9, 2016
Priority date	Nov 19, 2015
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

An inspection system that may include a motion device, for supporting an inspected object and for moving the inspected object, in response to motion device triggering signals, by a movement that is characterized by speed variations; a signal generator, for generating camera triggering signals and motion device location triggering signals; a motion device location generator, for providing location information indicative of locations of the stage at points of time that are determined by the motion device location triggering signals; a continuous illuminator for continuously illuminating areas of the inspected object; and a camera for acquiring images of areas of the inspected object in response to the camera triggering signals.

First claim

We claim:

1. An inspection system, comprising:
a motion device, for supporting an inspected object and for moving the inspected object, in response to motion device triggering signals, by a movement that is characterized by speed variations; wherein the motion device comprises a stage;
a signal generator, for generating at a fixed frequency regardless of the speed variations, camera triggering signals, the motion device triggering signals and stage location triggering signals;
a motion device location generator, for providing location information indicative of locations of the at points of time that are determined by the stage location triggering signals;
a continuous illuminator for continuously illuminating areas of the inspected object; and
a camera for acquiring images of areas of the inspected object in response to the camera triggering signals;
wherein overlaps between the images of the areas of the inspected object are characterized by overlap variations; and wherein the processor is configured to compensate for the overlap variations.

2. The inspection system according to claim 1 , wherein the signal generator is configured to generate the camera triggering signals and the motion device location triggering signals at a fixed frequency regardless of the speed variations.

3. The inspection system according to claim 2 , wherein the signal generator is configured to generate the camera triggering signals and the motion device location triggering signals at a fixed frequency regardless of the speed variations.

4. The inspection system according to claim 1 , wherein the signal generator is configured to generate the camera triggering signals and the motion device triggering signals in response to timing constraints that include timing differences between propagation periods of the camera triggering signals and the motion device triggering signals.

5. The inspection system according to claim 1 , wherein the stage is configured to reverse a direction of movement of the inspected object by a gradual change of direction of movement along each axis out of two axes.

6. The inspection system according to claim 1 , wherein the motion device is configured to move the inspected object according to a curved pattern.

7. The inspection system according to claim 1 , wherein the motion device is configured to move the inspected object without stopping a movement of the inspected object according to a hybrid pattern that comprises linear portions and curved portions.

8. The inspection system according to claim 1 wherein the image processor is configured to generate an image of a region that includes two or more areas of the areas of the inspected object; wherein the generating of the image of the region is responsive to location information indicative of locations of the stage at points of time that are correspond to an acquisitions of images of the two or more areas.

9. The inspection system according to claim 1 wherein the continuous illuminator is configured to continuously illuminating areas of the inspected object with a continuous light beam of a varying intensity.

10. The inspection system according to claim 9 wherein the continuous illuminator is configured to increase an intensity of the continuous light beam before a beginning of an image acquisition period during which the camera acquired an image and to decrease the intensity of the continuous light beam after an end of the image acquisition period.

11. The inspection system according to claim 9 wherein the signal generator is configured to generate at the fixed frequency regardless of the speed variations, continuous illuminator triggering signals; and wherein the continuous illuminator is configured to change the intensity of the continuous light beam in response to the continuous illuminator triggering signals.

12. A method, comprising:
supporting, by a motion device, an inspected object and for moving the inspected object by a movement that is characterized by speed variations; wherein the motion device comprises a stage;
generating, by a signal generator, at a fixed frequency regardless of the speed variations, camera triggering signals, motion device triggering signals and stage location triggering signals;
providing, by a stage location generator, location information indicative of a location of the stage at points of time that are determined by the stage location triggering signals;
continuously illuminating, by a continuous illuminator, illuminating areas of the inspected object; and
acquiring, by a camera, images of areas of the inspected object in response to the camera triggering signals;
wherein overlaps between the images of the areas of the inspected object are characterized by overlap variations; and wherein the method comprises compensating by the image processor for the overlap variations.

13. The method according to claim 12 , comprising generating the camera triggering signals and the motion device location triggering signals at a fixed frequency regardless of the speed variations.

14. The method according to claim 13 , comprising generating at the fixed frequency the motion device triggering signals.

15. The method according to claim 12 , comprising generating the camera triggering signals and the motion device location triggering signals in response to timing constraints that include timing differences between propagation periods of the camera triggering signals and the motion device location triggering signals.

16. The method according to claim 12 , comprising reversing, by the motion device, a direction of movement of the inspected object by a gradual change of direction of movement along each axis out of two axes.

17. The method according to claim 12 , comprising moving the inspected object according to a curved pattern.

18. The method according to claim 12 , comprising moving the inspected object without stopping a movement of the inspected object according to a hybrid pattern that comprises linear portions and curved portions.

19. The method according to claim 12 , comprising generating, by the image processor, an image of a region that includes two or more areas of the inspected object; wherein the generating of the image of the region is responsive to location information indicative of locations of the stage at points of time that correspond to an acquisition of images of the two or more areas.

20. The method according to claim 12 comprising continuously illuminating areas of the inspected object with a continuous light beam of a varying intensity.

21. The method according to claim 20 comprising increasing an intensity of the continuous light beam before a beginning of an image acquisition period during which the camera acquired an image and decreasing the intensity of the continuous light beam after an end of the image acquisition period.

22. The method according to claim 20 comprising generating continuous illuminator triggering signals; and changing the intensity of the continuous light beam in response to the continuous illuminator triggering signals.

Assignees

• Camtek Ltd

Inventors

• Koren Shimon
• Regensburger Menachem
• Ben-Ezer Zehava

Classifications

• H10P74/00

  Testing or measuring during manufacture or treatment of wafers, substrates or devices · CPC title

• H04N23/56

  provided with illuminating means · CPC title

• H04N5/2256

  Electricity · mapped topic

• H01L22/00

  Electricity · mapped topic

• G06T3/0068 Primary

  Physics · mapped topic