Low-E glazing performance by seed structure optimization
View Patent ↗A bi-layer seed layer can exhibit good seed property for an infrared reflective layer, together with improved thermal stability. The bi-layer seed layer can include a thin zinc oxide layer having a desired crystallographic orientation for a silver infrared reflective layer disposed on a bottom layer having a desired thermal stability. The thermal stable layer can include aluminum, magnesium, or bismuth doped tin oxide (AlSnO, MgSnO, or BiSnO), which can have better thermal stability than zinc oxide but poorer lattice matching for serving as a seed layer template for silver (111).
1. A low emissivity panel, comprising:
a transparent substrate;
a first layer formed above the transparent substrate, wherein the first layer consists of bismuth doped tin oxide with a doping concentration between 3 and 35 wt %; and
a second layer formed above the transparent substrate and first layer, wherein the second layer is operable as an infrared reflective layer.
2. The low emissivity panel of claim 1 further comprising a third layer formed between the first layer and the second layer, and wherein the third layer comprises zinc oxide and is formed directly on the first layer, and the second layer is formed directly on the third layer.
3. The low emissivity panel of claim 1 wherein the first layer has a thickness between 6 nm and 50 nm, and the second layer has a thickness of less than about 8 nm.
4. The low emissivity panel of claim 3 wherein the second layer comprises silver.
5. A low emissivity panel, comprising:
a transparent substrate;
a lower protective layer formed above the transparent substrate, wherein the lower protective layer comprises a nitride material;
a lower oxide layer formed above the lower protective layer, wherein the lower oxide layer comprises a metal oxide or a metal alloy oxide;
a thermal stability layer formed above the lower oxide layer, wherein the thermal stability layer consists of bismuth doped tin oxide with a doping concentration between 3 and 35 wt %;
a seed layer formed directly on the thermal stability layer, wherein the seed layer comprises zinc oxide having a (002) crystallographic orientation;
a reflective layer formed directly on the seed layer, wherein the reflective layer comprises silver having a (111) crystallographic orientation; and
a barrier layer formed above the reflective layer, wherein the barrier layer comprises at least one of titanium, nickel, or a combination thereof.
6. The low emissivity panel of claim 5 wherein the thermal stability layer has a thickness between 6 nm and 50 nm.
7. The low emissivity panel of claim 6 wherein the seed layer has a thickness of less than about 8 nm.
8. The low emissivity panel of claim 5 further comprising an upper oxide layer formed above the barrier layer, wherein the upper oxide layer comprises at least one of titanium dioxide, silicon nitride, silicon dioxide, silicon oxynitride, niobium oxide, silicon zirconium nitride, tin oxide, zinc oxide, or a combination thereof.
9. The low emissivity panel of claim 8 further comprising an optical filler layer formed above the upper oxide layer, wherein the optical filler layer comprises tin oxide.
10. The low emissivity panel of claim 9 further comprising an upper protective layer formed above the optical filler layer, wherein the upper protective layer comprises at least one of silicon nitride, silicon oxynitride, titanium oxide, tin oxide, zinc oxide, niobium oxide, silicon zirconium nitride, or a combination thereof.