Patterning of multi-depth optical devices

Patent metadata

Field	Value
Publication number	US-2020326621-A1
Application number	US-202016844636-A
Country	US
Kind code	A1
Filing date	Apr 9, 2020
Priority date	Apr 11, 2019
Publication date	Oct 15, 2020
Grant date	—

Abstract

Methods for patterning of multi-depth layers for the fabrication of optical devices are provided. In one embodiment, a method is provided that includes disposing a resist layer over a device layer disposed over a top surface of a substrate, the device layer having a first portion and a second portion, patterning the resist layer to form a first resist layer pattern having a plurality of first openings and a second resist layer pattern having a plurality of second openings, and etching exposed portions of the device layer defined by the plurality of first openings and the plurality of second openings, wherein the plurality of first openings are configured to form at least a portion of a plurality of first structures within the optical device, and the plurality of second openings are configured to form at least a portion of a plurality of second structures within the optical device.

First claim

What is claimed is:

1 . A method of forming an optical device, comprising:
disposing a resist layer over a device layer disposed over a top surface of a substrate, the device layer having:
a first portion having a first height from the top surface of the substrate; and
a second portion having a second height from the top surface of the substrate;
patterning the resist layer to:
form a first resist layer pattern having a plurality of first openings formed therein over the first portion of the device layer; and
form a second resist layer pattern having a plurality of second openings formed therein over the second portion of the device layer; and
etching exposed portions of the device layer defined by the plurality of first openings and the plurality of second openings, wherein
the plurality of first openings in the first resist layer pattern are configured to form at least a portion of a plurality of first structures within the optical device, and the first structures have a first depth relative to the top surface of the substrate, and
the plurality of second openings in the second resist layer pattern are configured to form at least a portion of a plurality of second structures within the optical device, and the second structures have a second depth relative to the top surface of the substrate.

2 . The method of claim 1 , wherein the etching the exposed portions of the device layer defined by the plurality of first openings and the plurality of second openings comprises at least one of ion implantation, ion beam etching (IBE), reactive ion etching (RIE), directional RIE, plasma etching, and thermal atomic layer etching.

3 . The method of claim 2 , wherein the device layer comprises one or more of titanium dioxide, zinc oxide, tin dioxide, aluminum-doped zinc oxide, fluorine-doped tin oxide, cadmium stannate, niobium oxide, zinc stannate, silicon nitride, and amorphous silicon containing materials.

4 . The method of claim 1 , wherein an etch stop layer is disposed on the substrate.

5 . The method of claim 4 , wherein the etch stop layer is non-transparent.

6 . The method of claim 1 , wherein the first depth is less than the second depth.

7 . The method of claim 1 , wherein the plurality of first structures and the plurality of second structures are perpendicular to the top surface of the substrate.

8 . The method of claim 1 , wherein the plurality of first structures and the plurality of second structures are at an angle relative to the top surface of the substrate.

9 . A method of forming an optical device, comprising:
disposing a hardmask over a device layer disposed over a top surface of a substrate, the device layer having:
a first portion having a first height from the top surface of the substrate; and
a second portion having a second height from the top surface of the substrate;
disposing a resist layer over the hardmask, the resist layer having a top surface parallel to the top surface of the substrate; patterning the resist layer to:
form a first resist layer pattern having a plurality of first openings formed therein over the first portion of the device layer; and
form a second resist layer pattern having a plurality of second openings formed therein over the second portion of the device layer;
etching exposed portions of the hardmask defined by the plurality of first openings and the plurality of second openings to:
expose unmasked first device layer segments of the first portion of the device layer; and
expose unmasked second device layer segments of the second portion of the device layer; and
etching the first device layer segments and the second device layer segments, wherein
the first device layer segments are configured to form at least a portion of a plurality of first structures within the optical device, and the first structures have a first depth relative to the top surface of the substrate; and
the second device layer segments are configured to form at least a portion of a plurality of second structures within the optical device, and the second structures have a second depth relative to the top surface of the substrate.

10 . The method of claim 9 , wherein the first depth is less than the second depth.

11 . The method of claim 9 , wherein the plurality of first structures and the plurality of second structures are perpendicular to the top surface of the substrate.

12 . The method of claim 9 , wherein the plurality of first structures and the plurality of second structures are at an angle relative to the top surface of the substrate.

13 . The method of claim 9 , wherein the hardmask is non-transparent.

14 . The method of claim 13 , further comprising:
removing the hardmask.

15 . A method of forming an optical device, comprising:
disposing a planarization layer over a device layer disposed over a top surface of a substrate, the device layer having:
a first portion having a first height from the top surface of the substrate; and
a second portion having a second height from the top surface of the substrate;
disposing a resist layer over the planarization layer; patterning the resist layer to:
form a first resist layer pattern having a plurality of first openings formed therein over the first portion of the device layer; and;
form a second resist layer pattern having a plurality of second openings formed therein over the second portion of the device layer;
etching exposed portions of the planarization layer defined by the plurality of first openings and the plurality of second openings to:
expose unmasked first device layer segments of the first portion of the device layer; and
expose unmasked second device layer segments of the second portion of the device layer; and
etching the first device layer segments and the second device layer segments, wherein
the first device layer segments are configured to form at least a portion of a plurality of first structures within the optical device, and the first structures have a first depth relative to the top surface of the substrate, and
the second device layer segments are configured to form at least a plurality of second structures within the optical device, and the second structures have a second depth relative to the top surface of the substrate.

16 . The method of claim 15 , wherein an etch stop layer is disposed on the substrate.

17 . The method of claim 16 , wherein the etch stop layer comprises a nitrogen-containing material.

18 . The method of claim 15 , wherein the first depth is less than the second depth.

19 . The method of claim 15 , wherein the plurality of first structures and the plurality of second structures are perpendicular to the top surface of the substrate.

20 . The method of claim 15 , wherein the plurality of first structures and the plurality of second structures are at an angle relative to the top surface of the substrate.

Assignees

• Applied Materials Inc

Inventors

• Godet Ludovic
• Chen Chien-An
• Cohen Brian Alexander
• Mcmillan Wayne
• Mcmackin Ian Matthew

Classifications

• G02B5/1857

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

• G02B5/0268

  characterized by the fabrication or manufacturing method · CPC title

• G02B1/12 Primary

  by surface treatment, e.g. by irradiation · CPC title

• G02B2006/12173

  Masking · CPC title

• G02B2006/12176

  Etching · CPC title