High bandwidth RF or microwave interconnects for optical modulators

Patent metadata

Field	Value
Publication number	US-10502987-B2
Application number	US-201615091307-A
Country	US
Kind code	B2
Filing date	Apr 5, 2016
Priority date	Apr 7, 2015
Publication date	Dec 10, 2019
Grant date	Dec 10, 2019

Abstract

A radio frequency (RF) interconnect for an optical modulator may comprise a circuit board to route a set of RF signals from a corresponding set of RF feeds to a substrate interface on a surface of a substrate of the optical modulator. The circuit board may be positioned along the surface of the substrate of the optical modulator. The circuit board may include a set of traces. A trace, of the set of traces, may be connected to a corresponding RF feed, of the set of RF feeds, at a height different than a height of the surface of the substrate of the optical modulator. The trace may be connected to the substrate interface.

First claim

What is claimed is:

1. A radio frequency (RF) interconnect for an optical modulator, the RF interconnect comprising:
a circuit board to route a set of RF signals from a corresponding set of RF feeds to a substrate interface, via an interposer interface, on a surface of a substrate of the optical modulator,
the interposer interface being aligned with the substrate interface in a vertical direction only,
the circuit board being positioned along the surface of the substrate of the optical modulator, and
the circuit board including a set of traces,
a trace, of the set of traces, being connected to a corresponding RF feed, of the set of RF feeds, at a height different than a height of the surface of the substrate of the optical modulator,
the trace being connected to the substrate interface; and

an interposer positioned in a cavity of the circuit board such that the set of traces are to be routed from the circuit board to the substrate interface via the interposer.

2. The RF interconnect of claim 1 , where the substrate interface is located at a start of, or within, an active region of the substrate of the optical modulator.

3. The RF interconnect of claim 1 , where the circuit board is to route the set of RF signals in a horizontal direction and a vertical direction within the circuit board.

4. The RF interconnect of claim 1 , where the set of RF feeds is positioned substantially parallel or substantially perpendicular to the surface of the substrate of the optical modulator.

5. The RF interconnect of claim 1 , where the circuit board includes a circuit board patterned interface on a surface of the circuit board,
the circuit board patterned interface connecting the set of traces to the substrate interface.

6. The RF interconnect of claim 5 , where the circuit board is positioned such that the circuit board patterned interface is aligned with the substrate interface,
a first amount of RF loss, associated with a substrate of the circuit board, being less than a second amount of RF loss associated with the substrate of the optical modulator, and
a first trace width, associated with the circuit board patterned interface, being greater than a second trace width associated with the substrate interface.

7. The RF interconnect of claim 5 , further comprising:
a conductive component comprising a micro-bump array, a micro-pipe array or a set if micro-copper pillars,
the circuit board patterned interface being connected to the substrate interface via the conductive component.

8. The RF interconnect of claim 1 , where the circuit board includes a center step.

9. An interconnect, comprising:
an interposer to route a signal from a signal feed to a substrate interface, via an interposer interface, of an optical modulator,
the interposer interface being aligned with the substrate interface in a vertical direction only,
the interposer being positioned along a surface of a substrate of the optical modulator, and
the interposer including a trace,
the trace being connected to the signal feed at a height different than a height of the surface of the substrate of the optical modulator, the trace being connected to the substrate interface, and the interposer including a cavity and another interposer,
the other interposer being positioned in the cavity of the interposer such that the trace is to be routed through or on the other interposer.

10. The interconnect of claim 9 , where the substrate interface is located at a start of, or within, an active region of the substrate of the optical modulator.

11. The interconnect of claim 9 , where the trace is to route the signal in a horizontal direction or a vertical direction within the interposer.

12. The interconnect of claim 9 , further comprising a conductive component comprising a micro-bump array, a micro-pipe array or a set if micro-copper pillars,
the trace being connected to the substrate interface via the conductive component.

13. The interconnect of claim 9 , where the interposer interface is located on a surface of the interposer,
the interposer interface being connected to the trace,
a configuration of the interposer interface matching a configuration of the substrate interface, and

the interposer is aligned with the interposer interface.

14. The interconnect of claim 9 , where the interposer includes a cavity,
the cavity being oriented such that one or more sides of the cavity are substantially orthogonal to one or more sides of the interposer.

15. The interconnect of claim 9 , where the interposer is a micro-air coaxial stack.

16. An electrical interconnect, comprising:
an interposer positioned along a substrate surface of an optical substrate,
the interposer including a trace associated with routing an electrical signal to an active region of the optical substrate via an interposer interface,
the interposer interface being aligned with the active region in a vertical direction only,
the interposer including a cavity that is oriented such that one or more sides of the cavity are substantially orthogonal to one or more sides of the interposer,
the trace being commenced on the interposer in a plane that is at a different height than a plane corresponding to the substrate surface, and
the trace connecting to a substrate interface of the optical substrate proximal to the active region.

17. The electrical interconnect of claim 16 , where the interposer includes a patterned interface on a surface of the interposer,
the patterned interface connecting the trace to the substrate interface, and
the patterned interface having a configuration complementary to a configuration of the substrate interface.

18. The electrical interconnect of claim 16 , where the interposer is to route the electrical signal to the substrate interface via a micro-bump array, a micro-pipe array, or a set of micro-copper pillars.

19. The RF interconnect of claim 1 , where at least one of a shape or a configuration of the interposer interface matches a corresponding shape or configuration of the substrate interface.

20. The RF interconnect of claim 1 , where the cavity that is oriented such that one or more sides of the cavity are substantially orthogonal to one or more sides of the interposer.

21. The electrical interconnect of claim 16 , where at least one of a shape or a configuration of the interposer interface matches a corresponding shape or configuration of the active region.

Assignees

• Lumentum Operations Llc

Inventors

• Cheung Siu Kwan
• Drake Glen
• Kissa Karl

Classifications

• H05K1/116

  Lands, clearance holes or other lay-out details concerning the surrounding of a via · CPC title

• H05K1/0222

  for shielding around a single via or around a group of vias, e.g. coaxial vias or vias surrounded by a grounded via fence · CPC title

• H05K2201/10356

  Cables · CPC title

• G02F1/011

  in optical waveguides, not otherwise provided for in this subclass · CPC title

• H05K2201/10962

  Component not directly connected to the PCB · CPC title