Opto-electronic sensor

Patent metadata

Field	Value
Publication number	US-9417186-B2
Application number	US-201213598841-A
Country	US
Kind code	B2
Filing date	Aug 30, 2012
Priority date	Aug 30, 2012
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

Some embodiments of the present disclosure relate to an infrared (IR) opto-electronic sensor having a silicon waveguide implemented on a single silicon integrated chip. The IR sensor has a semiconductor substrate having a silicon waveguide extends along a length between a radiation input conduit and a radiation output conduit. The radiation input conduit couples radiation into the silicon waveguide, while the radiation output conduit couples radiation out from the silicon waveguide. The silicon waveguide conveys the IR radiation from the radiation input conduit to the radiation output conduit at a single mode. As the radiation is conveyed by the silicon waveguide, an evanescent field is formed that extends outward from the silicon waveguide to interact with a sample positioned between the radiation input conduit and the radiation output conduit.

First claim

What is claimed is:

1. An infrared opto-electronic (IR) sensor, comprising:
a semiconductor substrate comprising a silicon waveguide consisting of silicon and continuously extending between a radiation input conduit configured to couple radiation into the silicon waveguide and a radiation output conduit configured to couple radiation from the silicon waveguide;
a buffer layer having a planar upper surface that continuously contacts a lower surface of the silicon waveguide between the radiation input conduit and the radiation output conduit, wherein the silicon waveguide is configured to convey the radiation from the radiation input conduit to the radiation output conduit at a single mode in a manner that results in an evanescent field that extends outward from the silicon waveguide to interact with a sample; and
a coupling element configured to couple radiation from a radiation source into the silicon waveguide, wherein the coupling element comprises a plurality of separate layers comprising different materials vertically extending from an upper surface of the silicon waveguide to the buffer layer and stacked in a direction horizontally extending along a length of the silicon waveguide.

2. The IR sensor of claim 1 , further comprising:
a radiation source configured to generate the radiation that is coupled into the silicon waveguide at the radiation input conduit; and
a radiation detector configured to measure one or more characteristics of the radiation is coupled from the silicon waveguide at the radiation output conduit.

3. The IR sensor of claim 1 , wherein the buffer layer is positioned between the semiconductor substrate and the silicon waveguide, wherein the buffer layer optically isolates the radiation from the semiconductor substrate.

4. The IR sensor of claim 3 , wherein the buffer layer comprises an amorphous carbon layer.

5. The IR sensor of claim 3 , further comprising:
one or more backside cavities positioned vertically below the silicon waveguide and vertically extending from a backside of the semiconductor substrate to the buffer layer.

6. The IR sensor of claim 3 , wherein the silicon waveguide comprises a rib waveguide comprising a silicon fin located above the buffer layer.

7. An infrared opto-electronic (IR) sensor, comprising:
an infrared radiation (IR) source configured to generate IR radiation having a wavelength in an infrared region of the electromagnetic spectrum;
an infrared radiation (IR) detector configured to measure one or more properties of the IR radiation;
a silicon substrate;
a buffer layer located above the silicon substrate; and
a layer of silicon material arranged over the buffer layer and comprising the IR source, the IR detector, and a silicon waveguide consisting of silicon, wherein the IR source and the IR detector are arranged within the layer of silicon material at locations laterally offset from the silicon waveguide.

8. The IR sensor of claim 7 , further comprising:
one or more backside cavities positioned vertically below the silicon waveguide and vertically extending from a backside of the silicon substrate to the buffer layer.

9. The IR sensor of claim 7 , wherein the silicon waveguide comprises a rib waveguide comprising a silicon fin located above the buffer layer.

10. The IR sensor of claim 1 ,
wherein the radiation detector is located along a backside of the semiconductor substrate that faces away from the silicon waveguide, and
wherein the radiation detector is in communication with the silicon waveguide by way of a first cavity in the backside of the semiconductor substrate which extends from a backside of the semiconductor substrate to the buffer layer.

11. The IR sensor of claim 3 , wherein the buffer layer is connected to the semiconductor substrate by way of an adhesion layer disposed between the buffer layer and the semiconductor substrate.

12. The IR sensor of claim 3 , wherein the buffer layer comprises a plurality of dielectric layers disposed on top of one another so as to form a plurality of interfaces at which different refractive indices meet.

13. The IR sensor of claim 7 ,
wherein the IR detector comprises an IR path that extends from the layer of silicon to a backside of the silicon substrate that faces away from the silicon waveguide, and
wherein the IR detector is in communication with the silicon waveguide by way of a first cavity in the backside of the silicon substrate which extends from a backside of the silicon substrate to the buffer layer.

14. The IR sensor of claim 7 , wherein the buffer layer comprises a plurality of dielectric layers disposed on top of one another so as to form a plurality of interfaces at which different refractive indices meet.

15. The IR sensor of claim 1 , wherein the coupling element is configured to provide thermal insulation between the radiation source and the silicon waveguide without significantly attenuating the radiation in an infrared region of the electromagnetic spectrum.

16. The IR sensor of claim 7 , further comprising:
a coupling element comprising one or more layers having a same height as the silicon waveguide and laterally arranged between the IR source and the silicon waveguide.

Assignees

• Jakoby Bernhard
• Lachiev Ventsislav
• Grille Thomas
• Irsigler Peter
• Hedenig Ursula
• Sgouridis Sokratis
• Ostermann Thomas Krotscheck
• Infineon Technologies Ag

Inventors

• Jakoby Bernhard
• Lachiev Ventsislav
• Grille Thomas
• Irsigler Peter
• Hedenig Ursula
• Sgouridis Sokratis
• Ostermann Thomas Krotscheck

Classifications

• G01N21/648

  using evanescent coupling or surface plasmon coupling for the excitation of fluorescence · CPC title

• G01N21/7703

  using reagent-clad optical fibres or optical waveguides (using measurement of total internal reflection or attenuated total reflection G01N21/552; optical fibres or waveguides per se G02B) · CPC title

• G01N21/552 Primary

  Attenuated total reflection · CPC title

• G01N21/7746

  the waveguide coupled to a cavity resonator · CPC title