Heat treatable coated article and method of making same
View Patent ↗A coated article or layer system is provided which includes at least one infrared (IR) reflecting layer including niobium (Nb) sandwiched between at least a pair of dielectric layers. In certain embodiments, a Cr inclusive barrier layer is provided to protect the Nb inclusive IR reflecting layer, for chemical durability purposes. In other example embodiments, a protective overcoat including a zirconium oxide inclusive layer may be provided to protect the Nb inclusive IR reflecting layer for durability purposes.
1. A coated article including a layer system supported by a glass substrate, the layer system comprising at least the following layers from the glass substrate outwardly:
a dielectric layer;
a first Cr inclusive barrier layer;
a first Nb inclusive IR reflecting layer located over and contacting the first Cr inclusive barrier layer;
a second Cr inclusive barrier layer located over and contacting the first Nb inclusive IR reflecting layer;
a second Nb inclusive IR reflecting layer located over and contacting the second Cr inclusive barrier layer;
a third Cr inclusive barrier layer located over and directly contacting the second Nb inclusive IR reflecting layer; and
another dielectric layer located over the third Cr inclusive barrier layer.
2. The coated article of claim 1 , wherein at least two of the Cr inclusive barrier layers comprises chromium nitride.
3. The coated article of claim 1 wherein at least one of the dielectric layers comprises silicon nitride.
4. The coated article of claim 1 , wherein the coated article is heat treated and has a ΔE* value (glass side reflective) of no greater than 3.0 after and/or due to heat treatment.
5. The coated article of claim 1 , wherein the coated article has a visible transmission of from 8 to 80%.
6. The coated article of claim 1 , wherein the coated article has a ΔE* value (glass side reflective) of no greater than 1.8 after and/or due to heat treatment.
7. The coated article of claim 1 , wherein at least two of the Cr inclusive barrier layers consist essentially of Cr or a nitride of Cr.
8. The coated article of claim 1 , wherein the coated article has no metallic infrared (IR) reflecting layer including Ag or Au.
9. The coated article of claim 1 , wherein the coated article is an IG window unit, a monolithic window, or a laminated window.
10. The coated article of claim 1 , wherein said another dielectric layer comprises silicon nitride and is in contact with the third Cr inclusive barrier layer.
11. The coated article of claim 1 , wherein the dielectric layer is in contact with the glass substrate and comprises silicon nitride and has an index of refraction “n” of from 1.9 to 2.2.