Method of manufacturing optical waveguide element

Patent metadata

Field	Value
Publication number	US-2025389893-A1
Application number	US-202519239025-A
Country	US
Kind code	A1
Filing date	Jun 16, 2025
Priority date	Jun 24, 2024
Publication date	Dec 25, 2025
Grant date	—

Abstract

A method of manufacturing an optical waveguide element includes: a step of preparing a structure including a substrate and a ridge-shaped optical waveguide layer provided on the substrate and made of a crystal material having an electro-optic effect; a step of depositing all of a cladding layer covering the optical waveguide layer; and a step of performing a heat treatment on the structure on which the cladding layer has been deposited.

First claim

What is claimed is:

1 . A method of manufacturing an optical waveguide element, comprising:
a step of preparing a structure including a substrate and a ridge-shaped optical waveguide layer provided on the substrate and made of a crystal material having an electro-optic effect; a step of depositing all of a cladding layer covering the optical waveguide layer; and a step of performing a heat treatment on the structure on which the cladding layer has been deposited.

2 . The method of manufacturing an optical waveguide element according to claim 1 , wherein a temperature of the heat treatment is 400° C. or more and 700° C. or less.

3 . A method of manufacturing an optical waveguide element, comprising:
a step of preparing a structure including a substrate and a ridge-shaped optical waveguide layer provided on the substrate and made of a crystal material having an electro-optic effect; a step of depositing a partial portion of a cladding layer covering the optical waveguide layer; a step of performing a heat treatment on the structure on which the partial portion of the cladding layer is deposited; and a step of depositing a remaining portion of the cladding layer so as to cover the partial portion of the cladding layer after the heat treatment.

4 . The method of manufacturing an optical waveguide element according to claim 3 , wherein a film thickness of the partial portion of the cladding layer is smaller than a film thickness of the remaining portion of the cladding layer.

5 . The method of manufacturing an optical waveguide element according to claim 3 , wherein a film thickness of the partial portion of the cladding layer is 10 nm or more and 100 nm or less.

6 . The method of manufacturing an optical waveguide element according to claim 3 , wherein a temperature of the heat treatment performed on the structure on which the partial portion of the cladding layer is deposited is 400° C. or more and 700° C. or less.

7 . The method of manufacturing an optical waveguide element according to claim 3 , further comprising a step of performing a heat treatment on the structure on which the cladding layer has been deposited by depositing the remaining portion of the cladding layer.

8 . The method of manufacturing an optical waveguide element according to claim 7 , wherein a temperature of the heat treatment performed on the structure on which the cladding layer has been deposited is 550° C. or more and 650° C. or less.

9 . The method of manufacturing an optical waveguide element according to claim 1 , wherein the step of preparing the structure comprises:
a step of forming a crystal film made of the crystal material on the substrate; a step of forming the optical waveguide layer by etching the crystal film; and a step of performing a heat treatment on the optical waveguide layer.

10 . The method of manufacturing an optical waveguide element according to claim 1 , wherein the crystal material is lithium niobate or lithium tantalate.

11 . The method of manufacturing an optical waveguide element according to claim 1 , wherein the optical waveguide layer has c-axis orientation.

12 . The method of manufacturing an optical waveguide element according to claim 1 , wherein the cladding layer is made of silicon oxide.

13 . The method of manufacturing an optical waveguide element according to claim 1 , further comprising:
a step of planarizing the cladding layer; a step of performing a heat treatment on the structure after the cladding layer is planarized; a step of depositing a buffer layer on the planarized cladding layer; a step of performing a heat treatment on the structure after the buffer layer is deposited; and a step of forming an electrode on the buffer layer.

Assignees

• Tdk Corp

Inventors

• Hara Hiroki
• Yoshinari Jiro
• Mieda Shigeru
• Sasaki Kenji

Classifications

• G02B2006/1204

  Lithium niobate (LiNbO3) · CPC title

• G02B2006/12097

  Ridge, rib or the like · CPC title

• G02B2006/12045

  Lithium tantalate (LiTaO3) · CPC title

• G02B2006/12169

  Annealing · CPC title

• G02F1/035 Primary

  in an optical waveguide structure · CPC title