HIGH REFRACTIVE INDEX WAVEGUIDES AND METHOD OF FABRICATION

• US 20180348431A1
• Filed: 12/02/2016
• Published: 12/06/2018
• Est. Priority Date: 12/02/2015
• Status: Active Grant

• Current Assignee: Trustees Of The University Of Pennsylvania (University of Pennsylvania)
• Original Assignee: Trustees Of The University Of Pennsylvania (University of Pennsylvania)
• Inventors: Bassett, Lee, Grote, Richard
• Granted Patent: US 10,585,243 B2
• Time in Patent Office: Days
• CPC Class Codes: G02B 2006/12035 Materials
• CPC Class Codes: G02B 2006/12038 Glass (SiO2 based materials)
• CPC Class Codes: G02B 2006/12088 Monomode
• CPC Class Codes: G02B 2006/12097 Ridge, rib or the like
• CPC Class Codes: G02B 2006/12173 Masking
• CPC Class Codes: G02B 6/12004 Combinations of two or more optical elements
• CPC Class Codes: G02B 6/1223 high refractive index type, i.e. high-contrast waveguides
• CPC Class Codes: G02B 6/132 by deposition of thin films
• CPC Class Codes: G02B 6/136 by etching

Abstract

Optical component and methods for forming optical components are described. The optical component includes a substrate having a base and a fin extending from the base, a buffer layer formed on the substrate leaving a portion of the fin exposed, and a confinement layer deposited over the buffer layer and the fin. The refractive index of the substrate is greater than the refractive index of the confinement layer, and the refractive index of the confinement layer is greater than the refractive index of the buffer layer.

Claims

1. A method for fabricating an optical component, comprising:

forming, on a substrate having a base and a fin extending from the base, a buffer layer leaving a portion of the fin exposed, the substrate having a first refractive index and the buffer material having a second refractive index; and

depositing a confinement layer over the buffer layer and the fin to form an optical waveguide, the confinement layer having a third refractive index;

wherein the first refractive index is greater than the third refractive index, and the third refractive index is greater than the second refractive index.

2. The method of claim 1, wherein;

the substrate is diamond, silicon or silicon carbide, the buffer layer is silicon dioxide, and the confinement layer is silicon nitride.

3. The method of claim 1, further comprising:

fabricating electronic circuitry and photonic integrated circuit devices on the substrate and connecting the electronic circuitry via the optical waveguide.

4. An optical component, comprising:

a substrate having a base and a fin extending from the base, the substrate having a first refractive index;

a buffer layer formed on the substrate leaving a portion of the fin exposed, the buffer layer having a second refractive index; and

a confinement layer deposited over the buffer layer and the fin, the confinement layer having a third refractive index;

wherein the first refractive index is greater than the third refractive index, and the third refractive index is greater than the second refractive index.

5. The optical component of claim 4, wherein;

the substrate is diamond, silicon or silicon carbide, the buffer layer is silicon dioxide, and the confinement layer is silicon nitride.

6. The optical component of claim 4, further comprising:

electronic circuitry and photonic integrated circuit devices fabricated on the substrate and connected via the optical waveguide.

7. A method for fabricating an optical component, comprising:

producing a hard mask on a substrate;

hard etching the substrate with the produced hard mask to create a fin;

depositing a low index material covering the fin;

removing at least a portion of the deposited low index material to expose a portion of the fin; and

depositing a high index material over the exposed portion of the fin to create the optical component.

8. The method of claim 7, further comprising:

exposing a cross section of the fin waveguide by laser cutting, cleaving, or etching to create a path for optical coupling with the optical component.

9. The method of claim 7, further comprising:

depositing the low index material by isotropically growing a first layer of the low index material on the etched substrate to cover the fin; and

removing the at least a portion of the deposited low index material by anisotropically etching the low-index material to expose the portion of a fin above a locally planar layer of low-index material.

10. The method of claim 7, further comprising:

depositing the low index material by isotropically growing a first layer of the low index material on the etched substrate to cover the fin; and

removing the at least a portion of the deposited low index material by;

planarizing the entire substrate, and

selectively etching the low index material to expose the portion of the fin above the planar layer of low-index material.