Visually detecting electrostatic discharge events

Patent metadata

Field	Value
Publication number	US-9711422-B2
Application number	US-201514821201-A
Country	US
Kind code	B2
Filing date	Aug 7, 2015
Priority date	Mar 28, 2012
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

Methods and structures provide an electrostatic discharge (ESD) indicator including an electric field sensitive material configured to undergo a specific color change in response to an electric field. An exposure of the structure to an ESD can be visually determined via the specific color change of the ESD indicator.

First claim

What is claimed:

1. A method comprising:
providing an electrostatic discharge (ESD) indicator on a surface of a structure, the ESD indicator comprising an electric field sensitive material configured to undergo a specific color change in response to an electric field and return back to its original color after a predetermined time period, the specific color change indicating a location, field strength, direction, and duration of an ESD event;
visually detecting an exposure of the structure to the ESD event via the specific color change of the ESD indicator between two or more different colors; and
quantifying a severity of the ESD event based on a color resulting from the specific color change,
wherein the electric field sensitive material comprises an electrochromistic material.

2. The method of claim 1 , wherein:
the structure comprises a semiconductor device; and
the providing comprises manufacturing the semiconductor device including the electric field sensitive material.

3. The method of claim 2 , wherein the manufacturing the semiconductor device including the electric field sensitive material comprises incorporating the electric field sensitive material in a layer of the semiconductor device.

4. The method of claim 1 , wherein:
the structure comprises a printed circuit board; and
the providing comprises manufacturing the printed circuit board including the electric field sensitive material.

5. The method of claim 1 , wherein the structure comprises a dedicated ESD detector in the form of a strip, puck, or plate.

6. The method of claim 1 , wherein the undergoing the specific color change comprises providing a visual indication of cumulative ESD exposure for the structure.

7. The method of claim 1 , wherein the electrochromistic material is a single electrochromistic material configured to vary between multiple different colors corresponding to different, predetermined ESD ranges.

8. The method of claim 1 , wherein the electrochromistic material comprises multiple variations where each variation is tuned to produce a different color corresponding to a different, predetermined ESD range.

9. The method of claim 1 , wherein the visually determining the color of the ESD indicator comprises:
encoding an image of the structure; and
correlating an area of the encoded image with a color reference.

10. The method of claim 1 , further comprising correlating the color of the ESD indicator with reference information corresponding to an ESD severity.

11. The method of claim 9 , further comprising recording an ESD event history of the structure, the ESD event history associating an identifier of structure with the reference information corresponding to the ESD severity, wherein the ESD event history of the structure associates the reference information corresponding to the ESD severity with one of a plurality of predefined steps in a process.

12. A structure comprising:
an object; and
an electrostatic discharge (ESD) indicator comprised of an electric field sensitive material,
wherein:
the ESD indicator is a coating attached to a surface of the object;
the ESD indicator is configured to change into one of a plurality of predetermined colors corresponding, respectively, to a plurality of predetermined electric field strength ranges, locations, directions and durations of an ESD event; and
the electric field sensitive material is composed of one of: (i) a single electrochromistic material configured to vary between multiple different colors corresponding to the plurality of predetermined electric field strength ranges; and (ii) multiple variations of an electrochromistic material where each variation is tuned to produce a different color corresponding to the plurality of predetermined electric field strength ranges.

13. The structure of claim 12 , wherein the electric field sensitive material is integrated within the object.

14. The structure of claim 12 , wherein the object is a semiconductor device.

15. The structure of claim 12 , wherein the object is a printed circuit board.

16. The structure of claim 12 , wherein the electric field sensitive material is included in an adhesive.

17. The structure of claim 12 , wherein the electric field sensitive material is included in a dry-film laminate.

18. The structure of claim 12 , wherein the electric field sensitive material is included in a fabric.

19. The structure of claim 12 , wherein the ESD indicator is configured to undergo a temporary color change.

Assignees

• Globalfoundries Inc

Inventors

• Ayotte Stephen P
• Hill David J
• Kinnear Jr John T
• Richard Glen E
• Sullivan Timothy M
• Truax Heather M

Classifications

• H10P74/235 Primary

  comprising optical enhancement of defects or not-directly-visible states · CPC title

• G01R31/002

  where the device under test is an electronic circuit · CPC title

• Y10T29/49124

  On flat or curved insulated base, e.g., printed circuit, etc. · CPC title

• H01L2924/00

  Electricity · mapped topic

• H01L22/24 Primary

  Electricity · mapped topic