Optical modulator robust to fabrication errors

Patent metadata

Field	Value
Publication number	US-10823988-B2
Application number	US-201816609069-A
Country	US
Kind code	B2
Filing date	Apr 12, 2018
Priority date	Apr 28, 2017
Publication date	Nov 3, 2020
Grant date	Nov 3, 2020

Abstract

An optical modulator includes a first arm and a second arm, each arm includes an arrangement with an equal amount of p-doped material and an equal amount of n-doped material, such that mask misalignment causes a same effect in both arms; and each arm includes a plurality of segments where electrodes connect for push-pull operation of the first arm and the second arm.

First claim

What is claimed is:

1. An optical modulator comprising:
a first arm and a second arm of an optical component, each arm includes an arrangement with an equal amount of p-doped material and an equal amount of n-doped material, wherein the arrangement of each arm is configured such that misalignment with a division line of p-n junctions overlapped by the optical component, resulting from mask misalignment, causes a same effect in both arms; and
each arm overlapping with a plurality of segments and electrodes connect to the plurality of segments for push-pull operation of the first arm and the second arm.

2. The optical modulator of claim 1 , wherein the optical component comprises a pattern of at least one of semiconductor, oxide, and metal formed on at least one of a wafer, die, and chip that superimposes fabrication patterns of the plurality of segments.

3. The optical modulator of claim 1 , wherein each segment of the plurality of segments includes a p-n junction overlapped by a corresponding one of the first arm and the second arm.

4. The optical modulator of claim 3 , wherein each arm overlaps with multiple p-n junctions resulting in each arm including the equal amount of p-doped material and the equal amount of the n-doped material independent of the misalignment of the multiple p-n junctions with the division line.

5. The optical modulator of claim 3 , wherein corresponding segments overlapped by the first arm and the second arm respectively are back-to-back junction components, the back-to-back junction components including one of a pnnp and a nppn configuration.

6. The optical modulator of claim 5 , wherein the back-to-back junction components are separated by a non-doped region.

7. The optical modulator of claim 1 , wherein corresponding segments overlapped by the first arm and the second arm respectively are back-to-back junction components.

8. An optical modulator circuit comprising:
a plurality of p-n junction segments; and
an optical component including a first arm and a second arm overlapping with corresponding segments of the plurality of p-n junction segments, the optical component including an arrangement where the first arm and the second arm include an equal amount of p-doped material and an equal amount of n-doped material, wherein the arrangement is configured such that misalignment with a division line of p-n junctions overlapped by the optical component, resulting from mask misalignment, causes a same effect in both the first arm and the second arm,
wherein electrodes connect to the plurality of p-n junction segments for push-pull operation of the first arm and the second arm.

9. The optical modulator circuit of claim 8 , wherein the optical component comprises a pattern of at least one of semiconductor, oxide, and metal formed on at least one of a wafer, die, and chip that superimposes fabrication patterns of the plurality of p-n junction segments.

10. The optical modulator circuit of claim 8 , wherein each segment of the plurality of p-n junction segments includes a p-n junction overlapped by a corresponding one of the first arm and the second arm.

11. The optical modulator circuit of claim 10 , wherein each arm overlaps with multiple p-n junctions resulting in each arm including the equal amount of p-doped material and the equal amount of the n-doped material independent of the misalignment of the multiple p-n junctions with the division line.

12. The optical modulator circuit of claim 10 , wherein corresponding segments overlapped by the first arm and the second arm respectively are back-to-back junction components, the back-to-back junction components including one of a pnnp and a nppn configuration.

13. The optical modulator circuit of claim 12 , wherein the back-to-back junction components are separated by a non-doped region.

14. The optical modulator circuit of claim 8 , wherein corresponding segments overlapped by the first arm and the second arm respectively are back-to-back junction components.

15. A method for forming an optical modulator circuit comprising:
forming a plurality of p-n junction segments to align p-n junctions of the p-n junction segments with a division line;
forming an optical component including a first arm and a second arm to overlap with corresponding segments of the plurality of p-n junction segments, wherein the optical component is formed with an arrangement where the first arm and the second arm include an equal amount of p-doped material and an equal amount of n-doped material, wherein the arrangement is configured such that misalignment with the division line of the p-n junctions overlapped by the optical component, resulting from mask misalignment, causes a same effect in both the first arm and the second arm,
wherein electrodes connect to the plurality of p-n junction segments for push-pull operation of the first arm and the second arm.

16. The method of claim 15 , wherein forming the optical component includes forming a pattern of at least one of semiconductor, oxide, and metal formed on at least one of a wafer, die, and chip that superimposes fabrication patterns of the plurality of p-n junction segments.

17. The method of claim 15 , wherein each segment of the plurality of p-n junction segments includes a p-n junction overlapped by a corresponding one of the first arm and the second arm.

18. The method of claim 17 , wherein each arm is formed to overlap with multiple p-n junctions resulting in each arm including the equal amount of p-doped material and the equal amount of the n-doped material independent of the misalignment of the multiple p-n junctions with the division line.

19. The method of claim 17 , wherein corresponding segments overlapped by the first arm and the second arm respectively are formed as back-to-back junction components, the back-to-back junction components including one of a pnnp and a nppn configuration.

20. The method of claim 19 , wherein the back-to-back junction components are separated by a non-doped region formed therebetween.

Assignees

• Ciena Corp

Inventors

• Latrasse Christine
• Painchaud Yves
• Poulin Michel

Classifications

• G02F1/0152

  using free carrier effects, e.g. plasma effect · CPC title

• G02F1/212

  Mach-Zehnder type · CPC title

• G02F1/2257

  the optical waveguides being made of semiconducting material · CPC title

• G02B2006/12061

  Silicon · CPC title

• G02F1/025 Primary

  in an optical waveguide structure (G02F1/017, {G02F1/2257} take precedence) · CPC title