Silicon chip with refractive index gradient for optical communication

Patent metadata

Field	Value
Publication number	US-9829663-B2
Application number	US-201415101009-A
Country	US
Kind code	B2
Filing date	Feb 25, 2014
Priority date	Feb 25, 2014
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

Technologies pertaining to a chip with a refractive index gradient, including fabrication thereof, are generally described. The refractive index gradient may be formed by creating atomic scale inclusions throughout a thickness of the chip by inducing nanoporosity into the chip, dissociating and diffusing oxygen into the chip, or performing chemical vapor deposition. One or more integrated circuit (IC) components and optical transceiver devices may be provided by mounting, growing, or etching the IC components and optical transceiver devices at a surface of the chip. The optical transceiver devices may be configured to transmit and/or receive an optical communication signal to and/or from at least one IC component or other optical transceiver device via an optical communication path within the thickness of the chip. The optical communication path may include a direction and distance, within the thickness of the chip, based on the refractive index gradient and angle of incidence.

First claim

What is claimed is:

1. An apparatus that includes optical communication capability, the apparatus comprising:
a chip;
a refractive index gradient formed from atomic scale inclusions across a thickness of the chip, wherein a density of the inclusions increases from a surface of the chip that comprises one or more integrated circuit (IC) components and one or more optical transceiver devices to an opposite surface of the chip;
the one or more IC components at the surface of the chip; and
the one or more optical transceiver devices at the surface of the chip and configured to transmit an optical communication signal to, or receive the optical communication signal from, at least one of the one or more IC components via an optical communication path, within the thickness of the chip,
wherein the optical communication path includes a direction and distance, within the thickness of the chip, that is based on the refractive index gradient and an angle of incidence.

2. The apparatus of claim 1 , wherein the one or more optical transceiver devices include at least one of a laser emitter or a laser detector.

3. The apparatus of claim 1 , wherein the refractive index decreases from the surface of the chip that comprises the one or more IC components and the one or more optical transceiver devices to the opposite surface of the chip.

4. The apparatus of claim 1 , wherein the inclusions have a lower refractive index than the chip.

5. The apparatus of claim 1 , further comprising:
a layer of conductive traces located at one of: the surface of the chip and within the thickness of the chip.

6. The apparatus of claim 5 , wherein a location of the layer of conductive traces is based on a density of the one or more IC components at the surface of the chip.

7. The apparatus of claim 1 , wherein the one or more optical transceiver devices are configured to at least one of statically project and dynamically project optical communication signals in one or more directions into the chip.

8. The apparatus of claim 7 , wherein a direction and an incident angle of a projected optical communication signal is based on a particular planar direction and a distance to be traveled by the projected optical communication signal.

9. The apparatus of claim 7 , wherein at least one of the optical communication signals includes a collimated beam that comprises one of: a laser beam, a visible light beam, and an infrared beam.

10. A method to fabricate a chip to facilitate optical communication, the method comprising:
forming a refractive index gradient by creating atomic scale inclusions across a thickness of the chip, wherein creating the atomic scale inclusions comprises forming the inclusions such that a density of the inclusions increases from a surface of the chip that comprises one or more integrated circuit (IC) components and one or more optical transceiver devices to an opposite surface of the chip;
forming the one or more IC components at the surface of the chip; and
providing the one or more optical transceiver devices at the surface of the chip, wherein the one or more optical transceiver devices are configured to transmit an optical communication signal to, or receive the optical communication signal from, at least one of the one or more IC components or other optical transceiver device via an optical communication path within the thickness of the chip, and wherein the optical communication path includes a direction and distance, within the thickness of the chip, that is based on the refractive index gradient formed and an angle of incidence.

11. The method of claim 10 , further comprising forming the chip of silicon.

12. The method of claim 10 , wherein the inclusions have a lower refractive index than the chip.

13. The method of claim 10 , wherein creating the atomic scale inclusions comprises forming the inclusions of silica.

14. The method of claim 10 , wherein creating the atomic scale inclusions comprises one of:
inducing nanoporosity into the chip;
dissociating and diffusing oxygen into the chip; and
performing chemical vapor deposition.

15. The method of claim 14 , wherein inducing the nanoporosity into the chip comprises inducing the nanoporosity into the chip via one of sputter deposition and anodization to create the inclusions.

16. The method of claim 14 , wherein dissociating and diffusing oxygen into the chip includes:
forming a layer of silica on the surface of the chip;
raising the layer of silica to a high temperature; and
keeping the layer of silica at the high temperature for a particular time period to dissociate and diffuse oxygen into the chip to create the inclusions.

17. The method of claim 14 , wherein performing the chemical vapor deposition comprises performing the chemical vapor deposition by silane deposition of silicon and introduction of increasing concentrations Of oxygen to create the inclusions.

18. The method of claim 10 , wherein providing the one or more optical transceiver devices at the surface of the chip includes at least one of: mounting, growing, and etching the one or more optical transceiver devices on the surface of the chip.

19. A method to operate a chip to facilitate optical communication, the method comprising:
outputting, an optical communication signal from a first optical transceiver device located at a surface of the chip, wherein the chip includes a refractive index gradient formed from atomic scale inclusions across a thickness of the chip, and wherein a density of the inclusions increases from the surface of the chip that comprises the first optical transceiver device to an opposite surface of the chip; and
propagating the optical communication signal from the first optical transceiver device to a second optical transceiver device, located at a same surface of the chip, via an optical communication path within the thickness of the chip, wherein the optical communication path includes a direction and distance, within the thickness of the chip, that is based on the refractive index gradient and an angle of incidence.

20. The method of claim 19 , wherein propagating the optical communication signal from the first optical transceiver device to the second optical transceiver device comprises one of statically projecting and dynamically projecting the optical communication signal.

21. The method of claim 19 , wherein a direction and an incident angle of the propagated optical communication signal is based on a particular planar direction and a distance to be traveled by the propagated optical communication signal via the optical communication path.

22. The method of claim 19 , wherein the chip comprises a first chip, wherein the optical communication signal comprises a first optical communication signal, and wherein the method further comprises transmitting a second optical communication signal from the first optical transceiver device to a third optical transceiver device located on a second chip, wherein the second chip is positioned beneath the first chip in a stacked formation.

Assignees

• Empire Technology Dev Llc

Inventors

• Millar Benjamin William

Classifications

• H04B10/801

  using optical interconnects, e.g. light coupled isolators, circuit board interconnections · CPC title

• G02B6/132

  by deposition of thin films · CPC title

• G02B6/122

  Basic optical elements, e.g. light-guiding paths · CPC title

• G02B6/43 Primary

  Arrangements comprising a plurality of opto-electronic elements and associated optical interconnections · CPC title

• G02B6/1342

  using diffusion (diffusion in single crystals C30B31/00; diffusion in glass C03C23/00) · CPC title