Variable height slanted grating method

Patent metadata

Field	Value
Publication number	US-11480724-B2
Application number	US-201917257767-A
Country	US
Kind code	B2
Filing date	Jul 1, 2019
Priority date	Jul 19, 2018
Publication date	Oct 25, 2022
Grant date	Oct 25, 2022

Abstract

An apparatus with a grating structure and a method for forming the same are disclosed. The grating structure includes forming a recess in a grating layer. A plurality of channels is formed in the grating layer to define slanted grating structures therein. The recess and the slanted grating structures are formed using a selective etch process.

First claim

What is claimed is:

1. A structure for use in a waveguide, comprising:
a substrate having a grating layer thereon, wherein a recessed structure is formed in the grating layer, the recessed structure comprising:
a first end;
a second end; and

a depth, wherein the depth changes from the first end to the second end; and
a plurality of channels formed in the grating layer below the recessed structure, each channel partially defining a portion of a plurality of grating structures, wherein:
bottom ends of the plurality of channels are coplanar;
top surfaces of the plurality of grating structures are coplanar and partially define the changing depth of the recessed structure; and

a depth of the plurality of grating structures changes from the first end to the second end defined by the recessed structure.

2. The structure of claim 1 , wherein the depth of the plurality of grating structures changes linearly from the first end to the second end.

3. The structure of claim 1 , wherein each grating structure has a depth between about 5 nm and about 700 nm.

4. The structure of claim 1 , wherein each grating structure is slanted at an angle between about 0 degrees and about 70 degrees.

5. The structure of claim 1 , wherein the grating layer is formed from an optically transparent material having a refractive index of about 1.3 or higher.

6. A structure for use in a waveguide, comprising:
a substrate having a grating layer thereon;
a recess formed in the grating layer, wherein the recess has a depth that changes a first direction, a second direction, and a third direction to define a three dimensional shape; and
a plurality of channels formed in the grating layer below the recess, each channel partially defining a portion of a plurality of grating structures, wherein bottom ends of the plurality of channels are coplanar, and wherein a depth of the plurality of grating structures changes in the first direction, the second direction, and the third direction as defined by the recess.

7. The structure of claim 6 , wherein the recess has a saddle-point shape.

8. The structure of claim 6 , wherein the recess has a positive curvature.

9. The structure of claim 6 , wherein the recess has a negative curvature.

10. The structure of claim 6 , wherein the grating layer is formed from an optically transparent material having a refractive index of about 1.3 or higher.

11. The structure of claim 6 , wherein each grating structure has a depth between about 5 nm and about 700 nm.

12. The structure of claim 6 , wherein each grating structure is slanted at an angle between about 0 degrees and about 70 degrees.

13. A structure for use in a waveguide, comprising:
a substrate having a grating layer thereon, wherein a recessed structure is formed in the grating layer, the recessed structure comprising:
a first end;
a second end; and

a depth, wherein the depth of the recessed structure changes from the first end to the second end; and
a plurality of channels formed in the grating layer below the recessed structure, each channel partially defining a portion of a plurality of grating structures, wherein bottom ends of the plurality of channels are coplanar, and wherein a depth of the plurality of grating structures changes non-linearly from the first end to the second end as defined by the recessed structure.

14. The structure of claim 13 , wherein the depth of the plurality of grating structures oscillates from the first end to the second end.

15. The structure of claim 13 , wherein the depth of the recess changes in the first direction and the second direction to define a curved shape.

16. The structure of claim 13 , wherein each grating structure has a depth between about 5 nm and about 700 nm.

17. The structure of claim 13 , wherein each grating structure is slanted at an angle between about 0 degrees and about 70 degrees.

18. The structure of claim 13 , wherein the grating layer is formed from an optically transparent material having a refractive index of about 1.3 or higher.

Assignees

• Applied Materials Inc

Inventors

• Evans Morgan
• Meyer Timmerman Thijssen Rutger

Classifications

• G02B5/1857 Primary

  using exposure or etching means, e.g. holography, photolithography, exposure to electron or ion beams · CPC title

• G02B6/0045 Primary

  by shaping at least a portion of the light guide · CPC title

• G02B6/0038

  Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide · CPC title

• G02B6/0016

  Grooves, prisms, gratings, scattering particles or rough surfaces · CPC title

• G02B27/0172

  characterised by optical features · CPC title