Extending the reflection bandwith of silver coating stacks for highly reflective mirrors
AssigneeCorning Incorporated
InventorsJason Scott Ballou, Gary Allen Hart, Leonard Gerard Wamboldt
Life of this patent
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Abstract
A highly reflective mirror for use in the wavelength range of 0.300 μm to 15 μm includes a substrate, a first interface layer, a reflective layer, a second interface layer, a plurality of tuning layers including a combination of a low index material and a high index material wherein the high index material is HfO2, and a protective layer. The highly reflective mirror has a reflectivity of at least 90% over the wavelength range of 335 nm to 1000 nm at an angle of incidence (AOI) of 45°.
Claims20
A highly reflective mirror for use in a wavelength range of 0.300 μm to 15 μm, the highly reflective mirror comprising:
- a substrate;
- a barrier layer comprising an abrasion resistant layer and a stress tuning layer;
- a first interface layer;
- a reflective layer;
- a second interface layer;
- a plurality of tuning layers comprising at least a first layer and a second layer, the first layer comprising a low refractive index material and the second layer comprising a high refractive index material, the high refractive index material comprising HfO2, and wherein the second layer has a thickness in a range of 20 nm to 60 nm and a total thickness of the plurality of tuning layers is in a range of 60 nm to 360 nm;
- and
- a protective layer,
- wherein the highly reflective mirror has a reflectivity of at least 90% over a wavelength range of 335 nm to 1000 nm at an angle of incidence (AOI) of 45°.
A method for making a highly reflective mirror for use in a wavelength range of 0.300 μm to 15 μm, the method comprising the steps of:
- providing a substrate;
- polishing the substrate to a roughness of less than 10 nm;
- applying a barrier layer on top of the substrate, the barrier layer comprising an abrasion resistant layer and a stress tuning layer;
- applying a first interface layer having a thickness in a range of 0.2 nm to 25 nm on top of the barrier layer;
- applying a reflective layer having a thickness in a range of 75 nm to 300 nm on top of the first interface layer;
- applying a second interface layer having a thickness in a range of 5 nm to 20 nm;
- applying a plurality of tuning layer comprising at least a first layer and a second layer, the first layer comprising a low refractive index material and the second layer comprising a high refractive index material, the high refractive index material comprising HfO2, and wherein the second layer has a thickness in a range of 20 nm to 60 nm and a total thickness of the plurality of tuning layers is in a range of 60 nm to 360 nm;
- and
- applying a protective layer on top of the plurality of tuning layers.
Dependencies are inferred from the claim text.