Transient antennas and transient electronics

Patent metadata

Field	Value
Publication number	US-9536844-B1
Application number	US-201514678512-A
Country	US
Kind code	B1
Filing date	Apr 3, 2015
Priority date	Apr 3, 2014
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

The disclosed antenna structures and electronic microsystems are capable of physically disappearing in a controlled, triggerable manner. Some variations provide an on-chip transient antenna comprising a semiconductor substrate containing ion-implanted hydrogen atoms and a conductor network comprising metals bridged by low-melting-temperature metals. Some variations provide an off-chip transient antenna comprising a flexible substrate containing a polymer, nanoporous silicon particles, and an oxidant for silicon, and a conductor network comprising metals bridged by low-melting-temperature metals. Other variations provide a method of introducing physical transience to a semiconductor integrated circuit, comprising thinning a substrate from the back side, implanting hydrogen ions into the thinned substrate to introduce latent structural flaws, depositing a semiconductor integrated circuit or sensor chip, and providing a controllable heating source capable of activating the latent structural flaws. These novel approaches are compatible with existing integrated circuits processing, preserve antenna performance, and use foundry-compatible techniques.

First claim

What is claimed is:

1. An on-chip transient antenna comprising:
(a) a semiconductor substrate having a front side and back side, wherein said semiconductor substrate contains ion-implanted interstitial hydrogen atoms, and wherein said semiconductor substrate is thermally disintegrable; and
(b) a conductor network, disposed on said front side of said semiconductor substrate, comprising a plurality of arrays of first metal conductors and second metal conductors, wherein said first metal conductors are bridged or strapped by said second metal conductors, and wherein said second metal conductors include one or more low-melting-temperature metals with melting point less than 750° C., or a metallic mesh.

2. The transient antenna of claim 1 , wherein said semiconductor substrate comprises one or more materials selected from the group consisting of silicon, silicon dioxide, aluminum oxide, sapphire, germanium, gallium arsenide, indium phosphide, silicon carbide, and combinations thereof.

3. The transient antenna of claim 1 , wherein said interstitial hydrogen atoms are ion-implanted from said back side of said semiconductor substrate.

4. The transient antenna of claim 1 , wherein said interstitial hydrogen atoms are disposed in a three-dimensional grid pattern within said semiconductor substrate.

5. The transient antenna of claim 1 , wherein said grid pattern is characterized by a grid spacing of about 200 microns or less.

6. The transient antenna of claim 1 , wherein said semiconductor substrate further contains a co-implant selected from the group consisting of boron, phosphorous, silicon, aluminum, germanium, carbon, gallium, indium, arsenic, and combinations thereof.

7. The transient antenna of claim 1 , wherein said semiconductor substrate comprises silicon, wherein said semiconductor substrate further contains co-implanted boron atoms, and wherein said interstitial hydrogen atoms and said boron atoms are ion-implanted from said back side of said semiconductor substrate.

8. The transient antenna of claim 1 , wherein said second metal conductors include indium, tin, aluminum, gold-indium alloy, copper-tin alloy, gold-tin alloy, a silver nanowire array, or a combination thereof.

9. The transient antenna of claim 1 , wherein said first metal conductors are bridged or strapped by said second metal conductors parallel and perpendicular relative to a conductor trace direction.

10. The transient antenna of claim 9 , wherein metal line widths of said first metal conductors and said second metal conductors are about 200 microns or less.

11. An off-chip transient antenna comprising:
(a) a flexible substrate containing a polymer, nanoporous silicon particles, and an oxidant for silicon, wherein said flexible substrate is thermally disintegrable; and
(b) a conductor network, disposed on said flexible substrate, comprising a plurality of arrays of first metal conductors and second metal conductors, wherein said first metal conductors are bridged or strapped by said second metal conductors, and wherein said second metal conductors include one or more low-melting-temperature metals with melting point less than 750° C., or a metallic mesh.

12. The transient antenna of claim 11 , wherein said polymer is selected from the group consisting of polyvinylfluoride, polytetrafluorethylene, polyvinylidene fluoride, polychlorotrifluoroethylene, perfluoroalkoxy polymer, polyethylenetetrafluoroethylene, and combinations thereof.

13. The transient antenna of claim 11 , wherein said oxidant for silicon is selected from the group consisting of a perchlorate, a perfluoropolymer, a metal oxide, a permanganate, sulfur, and combinations, precursors, or derivatives thereof.

14. The transient antenna of claim 11 , wherein said second metal conductors include indium, tin, aluminum, gold-indium alloy, copper-tin alloy, gold-tin alloy, a silver nanowire array, or a combination thereof.

15. The transient antenna of claim 11 , wherein said first metal conductors are bridged or strapped by said second metal conductors parallel and perpendicular relative to a conductor trace direction.

16. The transient antenna of claim 15 , wherein metal line widths of said first metal conductors and said second metal conductors are about 200 microns or less.

17. An off-chip transient antenna comprising:
(a) a flexible substrate containing a polymer, nanoporous silicon particles and an oxidant for silicon, wherein said flexible polymeric substrate is thermally disintegrable; and
(b) a conductor, disposed on said flexible substrate, comprising a shape-changing nanowire that recoils into nanospheres upon heating.

18. The transient antenna of claim 17 , wherein said polymer is selected from the group consisting of polyvinylfluoride, polytetrafluorethylene, polyvinylidene fluoride, polychlorotrifluoroethylene, perfluoroalkoxy polymer, polyethylenetetrafluoroethylene, and combinations thereof.

19. The transient antenna of claim 17 , wherein said oxidant for silicon is selected from the group consisting of a perchlorate, a perfluoropolymer, a metal oxide, a permanganate, sulfur, and combinations, precursors, or derivatives thereof.

20. The transient antenna of claim 17 , wherein said nanowire comprises silver.

Assignees

• Hrl Lab Llc

Inventors

• Brewer Peter D
• Wheeler Dana C
• Hussain Tahir
• Son Kyung-Ah
• Song Hyok J
• Moyer Harris P
• Colburn Joseph S
• Schaffner James H

Classifications

• H10W90/754

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W72/884

  Die-attach connectors and bond wires · CPC title

• H10W44/248

  for antennas · CPC title

• H10W42/40

  protecting against tampering, e.g. unauthorised inspection or reverse engineering · CPC title

• H10W44/20 Primary

  at high-frequency [HF] or radio frequency [RF] · CPC title