Devices and techniques for integrated optical data communication

Patent metadata

Field	Value
Publication number	US-10135539-B2
Application number	US-201314436613-A
Country	US
Kind code	B2
Filing date	Feb 15, 2013
Priority date	Oct 19, 2012
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

Devices and techniques for integrated optical data communication. A method of encoding symbols in an optical signal may include encoding a first symbol by injecting charge carriers, at a first rate, into a semiconductor device, such as a PIN diode. The method may also include encoding a second symbol by injecting charge carriers, at a second rate, into the semiconductor device. The first rate may exceed the second rate. A modulator driver circuit may include a resistive circuit coupled between supply terminal and drive terminals. The modulator driver circuit may also include a control circuit coupled between a data terminal and the resistive circuit. The control circuit may modulate a resistance of the resistive circuit by selectively coupling one or more of a plurality of portions of the resistive circuit to the drive terminal based on data to be optically encoded. In some embodiments, a modulator driver circuit and an optical modulator may be integrated on the same die or stacked (3D integrated) die and connected with through-oxide or through-silicon vias.

First claim

What is claimed is:

1. A method of fabricating an integrated circuit in a manufacturing process, comprising:
in a silicon layer of the manufacturing process, fabricating a body of a transistor of a modulator driver circuit configured to control an optical modulator, the transistor being configured to modulate a resistance between an optical modulator and a supply, wherein the silicon layer is a first layer of the manufacturing process;
in a second layer of the manufacturing process, fabricating a gate of the transistor of the modulator driver circuit;
fabricating an optical waveguide core in the silicon layer of the manufacturing process; and
fabricating a diode in the silicon layer of the manufacturing process, wherein a portion of the optical waveguide core is embedded in a portion of the diode.

2. The method of claim 1 , wherein the manufacturing process is a bulk silicon process.

3. The method of claim 1 , wherein the manufacturing process is a 65 nm process, a 45 nm process, a 32 nm process, or a 28 nm process.

4. The method of claim 1 , wherein the manufacturing process is a silicon-on-insulator (SOI) process.

5. The method of claim 1 , wherein the silicon layer is doped.

6. The method of claim 1 , wherein the second layer of the manufacturing process comprises a poly-silicon layer.

7. The method of claim 1 , further comprising capping the second layer of the manufacturing process with a layer of nickel silicide.

8. The method of claim 1 , wherein the second layer of the manufacturing process has a thickness that is between 65 nm and 200 nm.

9. The method of claim 1 , further comprising fabricating an optical resonator in the silicon layer of the manufacturing process.

10. The method of claim 1 , wherein fabricating the optical waveguide core comprises fabricating at least one waveguide core selected from the group consisting of a rib waveguide core and a strip waveguide core.

11. The method of claim 1 , wherein fabricating the diode comprises fabricating at least one diode selected from the group consisting of a PIN diode and a PN junction diode.

Assignees

• Massachusetts Inst Technology

Inventors

• Moss Benjamin Roy
• Orcutt Jason Scott
• Stojanovic Vladimir Marko

Classifications

• G02F1/025

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

• G02F1/0123

  Circuits for the control or stabilisation of the bias voltage, e.g. automatic bias control [ABC] feedback loops · CPC title

• G02F1/0121

  Operation of devices; Circuit arrangements, not otherwise provided for in this subclass · CPC title

• G02F2203/15

  involving resonance effects, e.g. resonantly enhanced interaction · CPC title

• H04B10/516 Primary

  Details of coding or modulation · CPC title