Silicon photonics device for LIDAR sensor and method for fabrication

Patent metadata

Field	Value
Publication number	US-12320925-B2
Application number	US-202418412119-A
Country	US
Kind code	B2
Filing date	Jan 12, 2024
Priority date	Nov 24, 2021
Publication date	Jun 3, 2025
Grant date	Jun 3, 2025

Abstract

A structure of a silicon photonics device for LIDAR includes a first insulating structure and a second insulating structure disposed above one or more etched silicon structures overlying a substrate member. A metal layer is disposed above the first insulating structure without a prior deposition of a diffusion barrier and adhesion layer. A thin insulating structure is disposed above the second insulating structure. A first configuration of the metal layer, the first insulating structure and the one or more etched silicon structures forms a free-space coupler. A second configuration of the thin insulating structure above the second insulating structure forms an edge coupler.

First claim

What is claimed is:

1. A silicon photonics device for a LIDAR sensor of a vehicle, comprising:
a substrate member; and
a first antenna of the LIDAR sensor formed on the substrate member, the first antenna being a one-dimensional grating coupler and including:
a first grating structure coupled to the substrate member; and
a first metal layer coupled to the first grating structure.

2. The silicon photonics device of claim 1 , further comprising:
an edge coupler formed on the substrate member, the edge coupler including:
a first dielectric structure coupled to the substrate member; and
a second dielectric structure coupled to the first dielectric structure.

3. The silicon photonics device of claim 2 , further comprising:
a second antenna of the LIDAR sensor formed on the substrate member, the second antenna including:
a second grating structure coupled to the substrate member;
a third dielectric structure coupled to the second grating structure; and
the first metal layer coupled to the third dielectric structure.

4. The silicon photonics device of claim 3 , further comprising:
a first frequency mixer formed on the substrate member and coupled to the first antenna; and
a second frequency mixer formed on the substrate member and coupled to the second antenna.

5. The silicon photonics device of claim 1 , wherein the first antenna further includes:
a diffusion barrier and adhesion layer on top of the first metal layer, the diffusion barrier and adhesion layer and the first metal layer forming a reflective mirror structure.

6. The silicon photonics device of claim 1 , further comprising a silicon-on-insulator (SOI) layer formed on the substrate member.

7. The silicon photonics device of claim 1 , wherein the first antenna further includes an intermediate oxide layer between the first grating structure and the first metal layer.

8. The silicon photonics device of claim 1 , wherein the first metal layer is a Metal 0 (MT0) layer.

9. The silicon photonics device of claim 1 , wherein a coupling loss of the first antenna is 0.25 decibels.

10. The silicon photonics device of claim 2 , wherein a thickness of the second dielectric structure is lesser than a thickness of the first dielectric structure.

11. The silicon photonics device of claim 2 , wherein the edge coupler includes an intermediate oxide layer between the first dielectric structure and the second dielectric structure.

12. The silicon photonics device of claim 5 , wherein the diffusion barrier and adhesion layer is one from a group of tantalum nitride, indium oxide, copper silicide, tungsten nitride, and titanium nitride.

13. The silicon photonics device of claim 5 , wherein a reflectivity of the first metal layer is higher than a reflectivity of the diffusion barrier and adhesion layer.

14. The silicon photonics device of claim 2 , wherein a distance between a top of the first dielectric structure and a bottom of the second dielectric structure is about 450 nanometers.

15. The silicon photonics device of claim 2 , wherein the second dielectric structure overlaps the first dielectric structure from edge to edge.

16. The silicon photonics device of claim 2 , wherein a height of the second dielectric structure is less than that of the first dielectric structure by a factor of about 3.

17. The silicon photonics device of claim 5 , wherein a height of the first metal layer is twice than that of the diffusion barrier and adhesion layer.

18. A LIDAR sensor for a vehicle, the LIDAR sensor comprising:
a silicon photonics device, the silicon photonics device including:
a substrate member; and
a first antenna of the LIDAR sensor formed on the substrate member, the first antenna being a one-dimensional grating coupler and including:
a first grating structure coupled to the substrate member; and
a first metal layer coupled to the first grating structure.

19. The LIDAR sensor of claim 18 , wherein the silicon photonics device further comprises:
a second antenna formed on the substrate member, the second antenna including:
a second grating structure coupled to the substrate member;
a first dielectric structure coupled to the second grating structure; and
the first metal layer coupled to the first dielectric structure.

20. An autonomous vehicle control system comprising:
a silicon photonics device for a LIDAR sensor of a vehicle, the silicon photonics device including:
a substrate member; and
an antenna of the LIDAR sensor formed on the substrate member, the antenna being a one-dimensional grating coupler and including:
a first grating structure coupled to the substrate member; and
a first metal layer coupled to the first grating structure.

Assignees

• Aurora Operations Inc

Inventors

• Lin Sen
• Michaels Andrew Steil

Classifications

• G01S17/931 Primary

  of land vehicles · CPC title

• H10F30/222

  the potential barrier being a PN heterojunction · CPC title

• H10F77/122

  comprising only Group IV materials · CPC title

• H10F77/413

  directly associated or integrated with the devices, e.g. back reflectors (directly associated or integrated with photovoltaic cells H10F77/42) · CPC title

• G01S17/34

  using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal · CPC title