Transient electronic device with ion-exchanged glass treated interposer

• US 10,262,954 B2
• Filed: 08/29/2017
• Issued: 04/16/2019
• Est. Priority Date: 04/23/2015
• Status: Active Grant

• Current Assignee: SRI International, Inc.
• Original Assignee: Palo Alto Research Center, Inc. (Xerox Holdings Corp.)
• Inventors: Limb, Scott J. H., Whiting, Gregory L.
• Primary Examiner(s): Choi, Calvin Y
• Application Number:
  US15/689,566
• Publication Number:
  US 20180005963A1
• Time in Patent Office: 595 Days
• Field of Search: None
• CPC Class Codes: H01L 21/4853 Connection or disconnection of other leads to or from a metallisation, e.g. pins, wires, bumps
• CPC Class Codes: H01L 21/486 Via connections through the substrate with or without pins
• CPC Class Codes: H01L 21/4864 Cleaning, e.g. removing of solder
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/131 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/16157 the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01L 2224/16235 the bump connector connecting to a via metallisation of the item
• CPC Class Codes: H01L 23/15 Ceramic or glass substrates H01L23/142, H01L23/145, H01L23/147 take precedence
• CPC Class Codes: H01L 23/49827 Via connections through the substrates, e.g. pins going through the substrate, coaxial cables H01L23/49822, H01L23/49833, H01L23/4985, H01L23/49861 take precedence
• CPC Class Codes: H01L 23/49838 Geometry or layout
• CPC Class Codes: H01L 23/49894 Materials of the insulating layers or coatings
• CPC Class Codes: H01L 23/57 Protection from inspection, reverse engineering or tampering
• CPC Class Codes: H01L 23/573 using passive means
• CPC Class Codes: H01L 23/576 using active circuits
• CPC Class Codes: H01L 24/00 Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
• CPC Class Codes: H01L 24/13 of an individual bump connector
• CPC Class Codes: H01L 24/16 of an individual bump connector
• CPC Class Codes: H01L 25/0655 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/014 Solder alloys
• CPC Class Codes: H01L 2924/15311 : being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/19105 : in a side-by-side arrangement on a common die mounting substrate
• CPC Class Codes: H03K 19/17768 : for security

Abstract

A transient electronic device utilizes a glass-based interposer that is treated using ion-exchange processing to increase its fragility, and includes a trigger device operably mounted on a surface thereof. An integrated circuit (IC) die is then bonded to the interposer, and the interposer is mounted to a package structure where it serves, under normal operating conditions, to operably connect the IC die to the package I/O pins/balls. During a transient event (e.g., when unauthorized tampering is detected), a trigger signal is transmitted to the trigger device, causing the trigger device to generate an initial fracture force that is applied onto the glass-based interposer substrate. The interposer is configured such that the initial fracture force propagates through the glass-based interposer substrate with sufficient energy to both entirely powderize the interposer, and to transfer to the IC die, whereby the IC die also powderizes (i.e., visually disappears).

Claims

1. A method for manufacturing a transient electronic device using comprising:

subjecting at least one interposer to an ion-exchange treatment, said at least one interposer including a glass substrate having a first surface and an opposing second surface, and including a trigger device on the glass substrate, said trigger device being configured to generate and apply an initial fracture force on said glass substrate in response to a trigger signal;

fixedly attaching an integrated circuit (IC) die to the treated glass substrate such that a plurality of IC contact points disposed in a first pattern on a surface of the semiconductor substrate are electrically connected to corresponding first interposer contact structures disposed on the first surface of the treated glass substrate; and

securing the interposer to a package structure such that a plurality of first package contact structures disposed in a second pattern on a surface of the package structure are electrically connected to corresponding second interposer contact structures disposed on the second surface of the treated glass substrate,

wherein subjecting the glass substrate to ion-exchange treatment comprises increasing an ion content of the glass substrate such that secondary fractures generated in said glass substrate in response to said initial fracture force propagate through said glass substrate, and

wherein fixedly attaching the IC die to the treated glass substrate comprises bonding the IC die such that the secondary fractures propagate into said IC die with sufficient energy to fracture said IC die.

2. The method of claim 1, wherein the method includes forming at least one interposer core comprising:

forming a plurality of through-glass via (TGV) openings that extend entirely through the glass substrate between the first surface and the second surface; and

forming a metal via structure in each of the plurality of TGV openings.

3. The method of claim 2, wherein forming the plurality of TGV openings comprises etching the glass substrate using one of a laser etching process, a mechanical etching process and a chemical etching process.

4. The method of claim 2, further comprising subjecting the glass substrate to a shallow ion-exchange process before forming said metal via structures.

5. The method of claim 2, wherein forming said metal via structures comprises:

depositing a metal material over the first surface and the second surface such that portions of the metal material enter each of the plurality of TGV openings and forms said metal via structures; and

removing residual portions of said metal material from the first surface and the second surface.

6. The method of claim 1,

wherein the at least one interposer comprises a plurality of interposers disposed on a single glass sheet configured such that the glass substrate of each of the plurality of interposers comprises a portion of the single glass sheet, and

wherein the method further comprises:

forming said first interposer contact structures on the first surface of said single glass sheet and said second interposer contact structures on the second surface of said single glass sheet;

dicing said single glass sheet to separate said plurality of interposers;

subjecting each of the plurality of interposers to said ion-exchange treatment; and

bonding an associated said IC die onto each of the plurality of interposers.

7. The method of claim 1,

wherein the at least one interposer comprises a plurality of interposers disposed on a single glass sheet configured such that the glass substrate of each of the plurality of interposers comprises a portion of the single glass sheet, and

wherein the method further comprises:

dicing said single glass sheet to separate said plurality of interposers;

subjecting each of the plurality of interposers to said ion-exchange treatment;

forming said first interposer contact structures on the first surface and said second interposer contact structures on the second surface of each said glass substrate of the plurality of interposers; and

bonding an associated said IC die onto each said glass substrate of the plurality of interposers.

8. The method of claim 1, wherein attaching said IC die to said glass substrate comprises using one of a sealing glass and an anodic bond.

9. The method of claim 8, wherein attaching said IC die to said glass substrate further comprises utilizing chemical mechanical polishing to reduce a thickness of the IC die.

10. A method for manufacturing a transient electronic device using comprising:

fixedly attaching an integrated circuit (IC) die to an interposer such that a plurality of IC contact points disposed in a first pattern on a surface of the semiconductor substrate are electrically connected to corresponding first interposer contact structures disposed on a first surface of the interposer; and

securing the interposer to a package structure such that a plurality of first package contact structures disposed in a second pattern on a surface of the package structure are electrically connected to corresponding second interposer contact structures disposed on a second surface of the interposer,

wherein the interposer comprises an ion-exchange treated glass substrate containing an amount of ions such that secondary fractures are generated in said glass substrate in response to an initial fracture force and propagate through said glass substrate, and

wherein fixedly attaching the IC die to the interposer comprises attaching the IC die to the ion-exchange treated glass substrate such that the secondary fractures propagate into said IC die.

11. The method of claim 10,

wherein the interposer comprises portion of a single glass sheet, and

wherein the method further comprises:

forming said first interposer contact structures on the first surface of said single glass sheet and said second interposer contact structures on the second surface of said single glass sheet;

dicing said single glass sheet to separate said interposer; and

subjecting said interposer to said ion-exchange treatment,

wherein fixedly attaching said IC die comprises bonding said IC die onto said glass substrate.

12. The method of claim 10,

wherein the interposer comprises a portion of a single glass sheet, and

wherein the method further comprises:

dicing said single glass sheet to separate said interposer;

subjecting said interposer to said ion-exchange treatment; and

forming said first interposer contact structures on the first surface and said second interposer contact structures on the second surface of said glass substrate,

wherein fixedly attaching said IC die comprises bonding said IC die onto said glass substrate.

13. The method of claim 10, wherein attaching said IC die to said glass substrate comprises using one of a sealing glass and an anodic bond.

14. The method of claim 13, wherein attaching said IC die to said glass substrate further comprises utilizing chemical mechanical polishing to reduce a thickness of the IC die.

15. A device, comprising:

an integrated circuit (IC) including a substrate having an electronic circuit formed thereon and IC contact pads disposed on a surface of the substrate and electrically coupled to the electronic circuit;

a package structure including a package substrate and a plurality of package contact structures disposed on a surface of the package substrate; and

an interposer disposed between the package structure and the IC and attached to the IC, the interposer configured to electrically connect the package contact structures to the IC contact pads, the interposer comprising a glass substrate configured such that secondary fractures generated in the glass substrate in response to an initial fracture force propagate through the glass substrate and the IC with sufficient energy to fracture the IC.

16. The device of claim 15, further comprising a trigger device attached to the interposer and configured to generate and apply the initial fracture force to the glass substrate in response to a trigger signal.

17. The device of claim 15, wherein the glass substrate comprises:

a plurality of through-glass vias extending between a first surface and a second surface of the glass substrate; and

a plurality of metal via structures, each metal via structure extending respectively through an associated through-glass via.

18. The device of claim 17, wherein the metal via structures comprise a conductive material having a Coefficient of Thermal Expansion (CTE) that is matched to a CTE of the glass substrate.

19. A device, comprising:

an integrated circuit (IC) including a substrate having an electronic circuit formed thereon and IC contact pads disposed on a surface of the substrate, the IC contact pads electrically coupled to the electronic circuit;

an interposer attached to the IC, the interposer including first electrical contacts configured to electrically connect to the IC contact pads, the interposer comprising a glass substrate configured such that secondary fractures generated in the glass substrate in response to an initial fracture force propagate through the glass substrate and the IC with sufficient energy to fracture the IC; and

a trigger device attached to the interposer and configured to generate and apply the initial fracture force to the glass substrate in response to a trigger signal.

20. The device of claim 19, wherein the glass substrate comprises:

a plurality of through-glass vias extending between a first surface and a second surface of the glass substrate;

a plurality of metal via structures, each metal structure extending respectively through an associated through-glass via; and

second contacts disposed on the second surface of the glass substrate, wherein the metal via structures electrically connect the first contacts to the second contacts.