PHOTONIC INTEGRATION PLATFORM

• US 20160077283A1
• Filed: 11/20/2015
• Published: 03/17/2016
• Est. Priority Date: 07/03/2013
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Webster, Mark, Tummidi, Ravi Sekhar
• Granted Patent: US 9,651,739 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G02B 2006/12038 Glass (SiO2 based materials)
• CPC Class Codes: G02B 2006/12061 Silicon
• CPC Class Codes: G02B 2006/121 Channel; buried or the like
• CPC Class Codes: G02B 2006/12147 Coupler
• CPC Class Codes: G02B 2006/12152 Mode converter
• CPC Class Codes: G02B 6/107 Subwavelength-diameter waveguides, e.g. nanowires
• CPC Class Codes: G02B 6/12 of the integrated circuit kind electric integrated circuits H01L27/00
• CPC Class Codes: G02B 6/12002 Three-dimensional structures
• CPC Class Codes: G02B 6/122 Basic optical elements, e.g. light-guiding paths
• CPC Class Codes: G02B 6/1228 Tapered waveguides, e.g. integrated spot-size transformers for coupling with fibres G02B6/305
• CPC Class Codes: G02B 6/132 by deposition of thin films
• CPC Class Codes: G02B 6/14 Mode converters
• CPC Class Codes: G02B 6/30 for use between fibre and thin-film device
• CPC Class Codes: G02B 6/305 and having an integrated mode-size expanding section, e.g. tapered waveguide
• CPC Class Codes: G02B 6/43 Arrangements comprising a plurality of opto-electronic elements and associated optical interconnections

Abstract

A SOI device may include a waveguide adapter that couples light between an external light source—e.g., a fiber optic cable or laser—and a silicon waveguide on the silicon surface layer of the SOI device. In one embodiment, the waveguide adapter is embedded into the insulator layer. Doing so may enable the waveguide adapter to be formed before the surface layer components are added onto the SOI device. Accordingly, fabrication techniques that use high-temperatures may be used without harming other components in the SOI device—e.g., the waveguide adapter is formed before heat-sensitive components are added to the silicon surface layer.

Claims

1. A silicon-on-insulator (SOI) optical device comprising:

a semiconductor substrate;

an insulation layer disposed above the substrate, wherein a waveguide is embedded in the insulation layer; and

a crystalline silicon layer above the insulation layer, the silicon layer comprising a silicon waveguide that overlaps the embedded waveguide such that an optical signal transmitted in the embedded waveguide is transferred to the silicon waveguide.

2. The SOI optical device of claim 1, wherein at least a portion of the embedded waveguide and a portion of the silicon waveguide are tapered where the embedded and silicon waveguides overlap in the optical device.

3. The SOI optical device of claim 1, wherein the embedded waveguide further comprises:

a waveguide adapter comprising multiple prongs exposed at an external coupling surface of the optical device, the external coupling surface is configured to couple to an external light source.

4. The SOI optical device of claim 3, wherein the waveguide adapter comprises a first prong that is disposed above a second prong in the insulation layer relative to the substrate, and wherein a dimension of the second prong decreases as the second prong extends away from the external coupling surface and a dimension of the first prong increases as the first prong extends away from the external coupling surface.

5. The SOI optical device of claim 3, wherein the substrate comprises a groove configured to passively align an external light source at the external coupling surface to introduce light into the multiple prongs of the waveguide adapter.

6. The SOI optical device of claim 1, wherein the embedded and silicon waveguides are spaced apart no more than 500 nanometers where the first and second waveguides overlap.

7. The SOI optical device of claim 1, wherein the insulation layer is a silicon type insulator and the embedded waveguide comprises one of silicon oxynitride and silicon nitride.

15. The SOI optical device of claim 1, wherein the insulation layer completely surrounds the first waveguide.

8-14. -14. (canceled)

16. A SOI optical device, comprising:

a first prong; and

a plurality of second prongs, wherein the first prong and second prongs are configured to at least one of receive and transmit optical energy via a coupling surface of an optical device,

wherein a dimension of the second prongs reduces as the second prongs extend in a direction away from the coupling surface,

wherein a dimension of the first prong increases as the first prong extends away from the coupling surface,

wherein a length of the first prong in the direction that extends away from the coupling surface is greater than each of the respective lengths of the second prongs.

17. The SOI optical device of claim 16, further comprising:

a semiconductor substrate;

an insulation layer disposed above the substrate; and

a crystalline silicon layer disposed above the insulation layer, wherein the first prong and the second prongs are disposed above the crystalline silicon layer.

18. The SOI optical device of claim 17, wherein the silicon layer comprises a silicon waveguide that overlaps at least one of the first prong and the second prongs such that the optical energy transmitted by the first prong and the plurality of second prongs is transferred to the silicon waveguide.

19. The SOI optical device of claim 17, wherein the first prong is located between the silicon layer and at least one of the second prongs.

20. The SOI optical device of claim 19, wherein the first prong is located between the silicon layer and all of the second prongs.

21. The SOI optical device of claim 16, wherein the first prong and second prongs terminate at one of:

(i) the coupling interface and (ii) a plane recessed from and parallel to the coupling interface.

22. A SOI optical device, comprising:

a semiconductor substrate;

an insulation layer disposed on the substrate;

a crystalline silicon layer disposed on the insulation layer and comprising a silicon waveguide; and

a waveguide adapter, wherein the silicon layer is disposed between the waveguide adapter and the insulation layer, the waveguide adapter comprising;

a first prong; and

a plurality of second prongs, wherein the first prong and second prongs are configured to at least one of receive and transmit optical energy via a coupling interface of the optical device,

wherein the first prong and the second prongs are positioned such that the optical energy transmitted by the first prong and the second prongs is transferred to the silicon waveguide, and

wherein the first prong is between at least one of the second prongs and the silicon waveguide.

23. The SOI optical device of claim 22, wherein each of the first prong and second prongs is surrounded by an insulative material such that none of the first or second prongs directly contact.

24. The SOI optical device of claim 22, wherein the first prong is located between the silicon layer and all of the second prongs, wherein a length of the second prongs extending from the coupling interface is the same.

25. The SOI optical device of claim 22, wherein the first prong and second prongs terminate at one of:

(i) the coupling interface and (ii) a plane recessed from and parallel to the coupling interface.

26. The SOI optical device of claim 22, wherein a dimension of the second prongs reduces as the second prongs extend in a direction away from the coupling surface, and wherein a dimension of the first prong increases as the first prong extends away from the coupling surface, wherein at least one of (i) the first prong and (ii) at least one of the second prongs overlaps the silicon waveguide such that an optical signal transmitted by the first prong and the second prongs is transferred to the silicon waveguide.

27. The SOI optical device of claim 26, wherein a length of the first prong in the direction that extends away from the coupling interface is greater than each of the respective lengths of the second prongs.