Method and system for a vertical junction high-speed phase modulator

• US 10,444,593 B2
• Filed: 09/01/2017
• Issued: 10/15/2019
• Est. Priority Date: 09/01/2016
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Luxtera Incorporated (Cisco Systems, Inc.)
• Inventors: Mekis, Attila, Sahni, Subal, De Koninck, Yannick, Masini, Gianlorenzo, Gholami, Faezeh
• Primary Examiner(s): Kianni, Kaveh C
• Application Number:
  US15/694,236
• Publication Number:
  US 20180059504A1
• Time in Patent Office: 774 Days
• Field of Search: 385 3, 385 14
• CPC Class Codes: G02F 1/025 in an optical waveguide structure G02F1/017, G02F1/2257 take precedence
• CPC Class Codes: G02F 1/21 by interference
• CPC Class Codes: G02F 1/212 Mach-Zehnder type
• CPC Class Codes: G02F 1/2257 the optical waveguides being made of semiconducting material
• CPC Class Codes: G02F 2201/063 ridge; rib; strip loaded
• CPC Class Codes: G02F 2201/12 electrode

Abstract

Methods and systems for a vertical junction high-speed phase modulator are disclosed and may include a semiconductor device having a semiconductor waveguide including a slab section, a rib section extending above the slab section, and raised ridges extending above the slab section on both sides of the rib section. The semiconductor device has a vertical pn junction with p-doped material and n-doped material arranged vertically with respect to each other in the rib and slab sections. The rib section may be either fully n-doped or p-doped in each cross-section along the semiconductor waveguide. Electrical connection to the p-doped and n-doped material may be enabled by forming contacts on the raised ridges, and electrical connection may be provided to the rib section from one of the contacts via periodically arranged sections of the semiconductor waveguide, where a cross-section of both the rib section and the slab section in the periodically arranged sections may be fully n-doped or fully p-doped.

Claims

1. A semiconductor device, the device comprising:

a semiconductor waveguide comprising a slab section, a rib section extending above the slab section, and raised ridges extending above the slab section on both sides of the rib section;

a vertical pn junction with p-doped material and n-doped material arranged vertically with respect to each other in the rib and slab sections, wherein the rib section is either fully n-doped or fully p-doped in each cross-section along the semiconductor waveguide;

contacts on the raised ridges that enable electrical connection to the p-doped material and n-doped material; and

wherein one of the contacts enables electrical connection to the rib section via periodically arranged sections of the semiconductor waveguide where a cross-section of both the rib section and the slab section in the periodically arranged sections is fully n-doped or fully p-doped.

2. The device according to claim 1, wherein the rib section is fully n-doped or fully p-doped along a full length of the semiconductor waveguide.

3. The device according to claim 1, wherein the rib section alternates between fully p-doped or fully n-doped in sections along a full length of the semiconductor waveguide.

4. The device according to claim 1, wherein the slab section alternates between fully p-doped or fully n-doped in sections along a full length of the semiconductor waveguide.

5. The device according to claim 1, wherein the slab section is fully n-doped or fully p-doped along a full length of the semiconductor waveguide except for in the periodically arranged sections.

6. The device according to claim 1, wherein the raised ridges are separated from the rib by trenches.

7. The device according to claim 1, wherein the semiconductor waveguide comprises a first phase modulation section of an optical modulator.

8. A method for communication, the method comprising:

in a semiconductor waveguide comprising;

a slab section, a rib section extending above the slab section, and raised ridges extending above the slab section on both sides of the rib section;

a vertical pn junction with p-doped material and n-doped material arranged vertically with respect to each other in the rib and slab sections, wherein the rib section is either fully n-doped or fully p-doped in each cross-section along the semiconductor waveguide;

contacts on the raised ridges to enable an electrical connection to the p-doped material and n-doped material; and

wherein one of the contacts enable an electrical connection to the rib section from via periodically arranged sections of the semiconductor waveguide where a cross-section of both the rib section and the slab section in the periodically arranged sections is fully n-doped or fully p-doped;

receiving a continuous-wave optical signal in the semiconductor waveguide; and

generating a modulated optical signal by applying a modulating voltage to the contacts.

9. The method according to claim 8, wherein the rib section is fully n-doped or fully p-doped along a full length of the semiconductor waveguide.

10. The method according to claim 8, wherein the rib section alternates between fully p-doped or fully n-doped in sections along a full length of the semiconductor waveguide.

11. The method according to claim 8, wherein the slab section alternates between fully p-doped or fully n-doped in sections along a full length of the semiconductor waveguide.

12. The method according to claim 8, wherein the slab section is fully n-doped or fully p-doped along a full length of the semiconductor waveguide except for in the periodically arranged sections.

13. The method according to claim 8, wherein the raised ridges are separated from the rib by trenches.

14. The method according to claim 8, wherein the semiconductor waveguide comprises a first phase modulation section of an optical modulator.