Methods of forming optical system components and optical coatings

• US 10,131,571 B2
• Filed: 05/12/2017
• Issued: 11/20/2018
• Est. Priority Date: 09/08/2015
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Oudard, Jean-Francois, Platten, James Edward, Wang, Jue
• Primary Examiner(s): Chen, Bret P
• Application Number:
  US15/593,961
• Publication Number:
  US 20170247290A1
• Time in Patent Office: 557 Days
• CPC Class Codes: C03C 17/245 by deposition from the vapour phase
• CPC Class Codes: C03C 17/2456 Coating containing TiO2
• CPC Class Codes: C03C 17/3417 all coatings being oxide coatings
• CPC Class Codes: C03C 2217/213 SiO2
• CPC Class Codes: C03C 2217/218 V2O5, Nb2O5, Ta2O5
• CPC Class Codes: C03C 2217/734 comprising an alternation of high and low refractive indexes
• CPC Class Codes: C03C 2218/153 by plasma-enhanced cvd
• CPC Class Codes: C23C 16/402 Silicon dioxide
• CPC Class Codes: C23C 16/405 of refractory metals or yttrium
• CPC Class Codes: C23C 16/50 using electric discharges generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34
• CPC Class Codes: C23C 16/513 using plasma jets
• CPC Class Codes: G02B 1/115 Multilayers
• CPC Class Codes: G02B 1/12 by surface treatment, e.g. by irradiation
• CPC Class Codes: G02B 1/18 Coatings for keeping optical surfaces clean, e.g. hydrophobic or photo-catalytic films G02B1/16 takes precedence
• CPC Class Codes: H01J 2237/327 Arrangements for generating the plasma
• CPC Class Codes: H01J 2237/3321 CVD [Chemical Vapor Deposition]
• CPC Class Codes: H01J 37/32009 Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources plasma generation in general H05H1/24

Abstract

A method of forming an optical coating, including the steps: depositing a buffer layer on a glass substrate via plasma deposition at a first plasma bias voltage; and depositing at least one layer of an optical coating on the buffer layer via plasma deposition, the deposition of the optical coating carried out at a second plasma bias voltage.

Claims

1. A method of forming an optical system component, comprising the steps of:

depositing a first portion of a first layer of an optical coating via plasma deposition on a glass substrate at a first plasma bias voltage, wherein the glass substrate comprises one or more fluorides and the first portion has a thickness from about 5 nm to about 10 nm and the overall thickness of the first layer is greater than about 20 nm;

depositing a second portion of the first layer of the optical coating via plasma deposition on the first portion at a second plasma bias voltage, wherein the second plasma bias voltage is greater than the first plasma bias voltage; and

depositing a second layer of the optical coating on the first layer.

2. The method of claim 1, wherein a thermal damage threshold of the glass substrate is less than about 500°

C.

3. The method of claim 2, wherein the first plasma bias voltage is between about 50 V and about 90 V.

4. The method of claim 1, wherein the first layer comprises a material having a refractive index greater than about 2.0.

5. The method of claim 1, wherein the first portion of the first layer has a packing density of about 90% or greater.

6. The method of claim 5, wherein the first portion and second portion of the first layer comprise a same dielectric material.

7. The method of claim 1, wherein the optical coating comprises layers of alternating dielectric materials, the first layer comprising at least one of Ta₂O₅, Nb₂O₅, TiO₂, and HfO₂, and the second layer comprising SiO₂.

8. The method of claim 1, wherein the glass substrate with the optical coating has a transmittance loss of the electromagnetic radiation of less than about 0.1% over an electromagnetic wavelength of about 350 nm to about 800 nm.

9. A method of forming an optical coating, comprising the steps:

providing a glass substrate;

depositing a buffer layer on the substrate via plasma deposition at a first plasma bias voltage; and

depositing at least one layer of an optical coating on the buffer layer via plasma deposition, the deposition of the optical coating carried out at a second plasma bias voltage,

wherein the second plasma bias voltage is greater than the first plasma bias voltage and the buffer layer has a packing density greater than about 94%.

10. The method of forming an optical coating of claim 9, wherein the first plasma bias voltage ranges from about 50 V to about 90 V and the second plasma bias voltage ranges from about 100 V to about 140 V.

11. The method of forming an optical coating of claim 10, wherein the glass substrate comprises at least one fluoride.

12. The method of forming an optical coating of claim 11, wherein at least one of the buffer layer and the optical coating layers has a non-uniform thickness across the glass substrate.

13. The method of forming an optical coating of claim 12, wherein the buffer layer and the at least one layer of the optical coating comprise the same material.

14. A method of forming an optical system component, comprising the steps:

depositing a buffer layer on a substrate comprising glass, wherein the buffer layer is deposited via plasma deposition at a first plasma bias voltage; and

depositing at least one layer of an optical coating on the buffer layer via plasma deposition, the deposition of the optical coating carried out at a second plasma bias voltage,

wherein the buffer layer has a packing density of about 94% or greater.

15. The method of forming an optical system component of claim 14, wherein at least one of the buffer layer and the optical coating has a non-uniform thickness across the substrate.

16. The method of forming an optical system component of claim 14, wherein the buffer layer and the at least one layer of the optical coating comprise the same material.

17. The method of forming an optical system component of claim 14, wherein the substrate comprises one or more fluorides and the buffer layer has a thickness between about 5 nm and about 10 nm.

18. The method of forming an optical system component of claim 14, wherein the first plasma bias voltage is between about 50 V and about 90 V.

19. The method of forming an optical system component of claim 14, wherein the optical coating comprises at least one of Ta₂O₅, Nb₂O₅, TiO₂, and HfO₂.