IP Library › Granted Patent US 12669723
Granted Patent B2
US 12669723 · App. 18/155,300 · Granted Jun 30, 2026

Embedded radio frequency shield between integrated optical modulator and silicon substrate

Inventors: Long Chen (Marlboro, NJ); Qianfan Xu (San Jose, CA); Li Chen (Marlboro, NJ); Mark A. Webster (Bethlehem, PA)
Assignee: CISCO TECHNOLOGY, INC.
G02F1/0356G02B6/13G02F1/025G02B2006/12142G02F1/2255G02F1/2257G02F2201/127G02F2201/501
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 12669723
App. No.
18/155,300
Granted
Jun 30, 2026
Kind
B2
Abstract

A device and a method of fabricating the device are provided. The device includes an optical modulator formed in a dielectric material, a silicon substrate adjacent the dielectric material, and a metal shield formed in the dielectric material between the optical modulator and the silicon substrate. The metal shield blocks an electromagnetic field of a driving signal of the optical modulator from extending into the silicon substrate.

Claims (28)

1 . A method comprising:

fabricating a first wafer, the first wafer including an optical modulator formed in a dielectric material, the optical modulator including a silicon diode electrically coupled to a plurality of electrodes;

fabricating a second wafer, the second wafer including a metal shield formed in the dielectric material on top of a silicon substrate, wherein the metal shield is a floating metal shield that includes a plurality of metal bars placed in a transverse direction of an electrode propagation direction of the optical modulator with a certain pitch;

inverting the first wafer to form an inverted first wafer; and

bonding the inverted first wafer to the second wafer such that the metal shield is positioned between the plurality of electrodes of the optical modulator and the silicon substrate.

2 . The method of claim 1 , wherein the metal shield is patterned to include the plurality of metal bars.

3 . The method of claim 1 , wherein the silicon substrate is a low resistivity silicon substrate.

4 . The method of claim 1 , wherein the floating metal shield is not connected to an electrode.

5 . The method of claim 1 , wherein each of the plurality of metal bars is isolated and not connected to other metal bars of the plurality of metal bars.

6 . The method of claim 1 , wherein the floating metal shield is positioned between the plurality of electrodes and the silicon substrate.

7 . The method of claim 1 , wherein the metal shield blocks an electromagnetic field emanating from the optical modulator from entering the silicon substrate.

8 . The method of claim 1 , wherein the plurality of metal bars of the metal shield are vertically separated from the plurality of electrodes.

9 . The method of claim 1 , wherein bonding the inverted first wafer to the second wafer includes bonding a first layer of the dielectric material of the first wafer to a second layer of the dielectric material of the second wafer.

10 . The method of claim 1 , wherein the plurality of metal bars are parallel to one another.

11 . A method comprising:

providing an optical modulator in a first layer of dielectric material;

providing a silicon substrate adjacent the first layer of dielectric material; and

providing a floating metal shield in a second layer of dielectric material between the optical modulator and the silicon substrate, the floating metal shield blocking an electromagnetic field of a driving signal of the optical modulator from extending into the silicon substrate, the floating metal shield including a plurality of metal bars positioned in a transverse direction of the driving signal with a certain pitch.

12 . The method of claim 11 , wherein the floating metal shield is not connected to an electrode.

13 . The method of claim 11 , wherein each of the plurality of metal bars is isolated and not connected to other metal bars of the plurality of metal bars.

14 . The method of claim 11 , wherein providing the floating metal shield in the second layer of dielectric material between the optical modulator and the silicon substrate further comprises:

bonding a first wafer to an inverted second wafer, the first wafer including the floating metal shield and the inverted second wafer including the optical modulator.

15 . The method of claim 11 , wherein the silicon substrate is a low resistivity silicon substrate.

16 . The method of claim 11 , wherein the floating metal shield is patterned to include the plurality of metal bars.

17 . The method of claim 11 , wherein the optical modulator includes a silicon diode electrically coupled to a plurality of electrodes, and wherein the floating metal shield is positioned between the plurality of electrodes and the silicon substrate.

18 . The method of claim 11 , wherein the floating metal shield blocks an electromagnetic field emanating from the optical modulator from entering the silicon substrate.

19 . The method of claim 11 , wherein the optical modulator includes a silicon diode electrically coupled to a plurality of electrodes, and wherein the plurality of metal bars of the floating metal shield are vertically separated from the plurality of electrodes.

20 . The method of claim 11 , wherein the plurality of metal bars are parallel to one another.