Method of forming optical waveguides in a semiconductor substrate

• US 20050211664A1
• Filed: 05/16/2005
• Published: 09/29/2005
• Est. Priority Date: 09/19/2001
• Status: Abandoned Application

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Kumar, Ajay, Khan, Anisul
• Application Number:
  US11/130,553
• Publication Number:
  US 20050211664A1
• Time in Patent Office: Days
• US Class Current: 216/24
• CPC Class Codes: G02B 2006/12061 Silicon
• CPC Class Codes: G02B 2006/12078 Gallium arsenide or alloys (GaAs, GaAlAs, GaAsP, GaInAs)
• CPC Class Codes: G02B 2006/12176 Etching
• CPC Class Codes: G02B 6/122 Basic optical elements, e.g. light-guiding paths
• CPC Class Codes: G02B 6/30 for use between fibre and thin-film device

Abstract

Embodiments of optical waveguides and method for their fabrication are provided herein. In one embodiment, a method of making an optical waveguide, includes the steps of providing a substrate comprising a semiconductor layer disposed on a first insulating layer. A hard mask is formed on the semiconductor layer. An opening is then etched in the semiconductor layer to expose a portion of the first insulating layer using the hard mask. A core material is deposited on the first insulating layer to fill the opening. The core material is then planarized and the hard mask removed. A top cladding layer is finally deposited over the core material.

Claims

1. A method of making an optical waveguide, comprising:

providing a substrate comprising a semiconductor layer disposed on a first insulating layer;

forming a hard mask on the semiconductor layer;

etching an opening in the semiconductor layer to expose a portion of the first insulating layer using the hard mask;

depositing a core material on the first insulating layer to fill the opening;

planarizing the core material;

removing the hard mask; and

depositing a top cladding layer over the core material.

2. The method of claim 1, wherein the semiconductor layer comprises silicon.

3. The method of claim 1, wherein the substrate further comprises a second insulating layer having the first insulating layer disposed thereon.

4. The method of claim 1, wherein the first insulating layer is comprised of at least one of glass or silicon oxide.

5. The method of claim 1, wherein the hard mask further comprises:

a silicon oxide layer formed over a silicon nitride layer.

6. The method of claim 1, wherein the core material contacts the semiconductor layer along a sidewall of the opening.

7. The method of claim 1, further comprising:

conformally depositing a bottom cladding layer in the opening, the bottom cladding layer having a different refractive index than the core material.

8. The method of claim 7, wherein the bottom cladding layer is silicon oxide.

9. The method of claim 7, wherein the step of planarizing further comprises:

removing a portion of the bottom cladding layer.

10. The method of claim 1, wherein the step of providing a substrate further comprises:

providing a substrate having integrated circuit features at least partially formed therein.

11. A method of making an optical waveguide, comprising:

providing a substrate comprising a semiconductor layer disposed on a first insulating layer;

depositing a silicon oxide layer over a silicon nitride layer on the semiconductor layer;

depositing a masking layer on the silicon oxide layer;

masking and patterning an opening in the masking layer;

etching through the silicon oxide and silicon nitride layers to form a hard mask;

etching an opening in the semiconductor layer to expose a portion of the first insulating layer;

depositing a core material on the first insulating layer to fill the opening;

planarizing the core material;

removing the silicon oxide layer and the silicon nitride layer; and

depositing a top cladding layer having a different refractive index than the core material.

12. The method of claim 11, wherein the semiconductor layer comprises silicon.

13. The method of claim 11, wherein the substrate further comprises a second insulating layer having the first insulating layer disposed thereon.

14. The method of claim 11, wherein the first insulating layer is comprised of at least one of glass or silicon oxide.

15. The method of claim 11, wherein the core material contacts the semiconductor layer along a sidewall of the opening.

16. The method of claim 11, wherein the step of providing a substrate further comprises:

providing a substrate having integrated circuit features at least partially formed therein.