Coated article with sputter-deposited transparent conductive coating for refrigeration/freezer units, and method of making the same
Certain example embodiments relate to sputter-deposited transparent conductive coatings (TCCs) for use in, for example, refrigeration and/or freezer units (e.g., as doors, windows, etc.). The TCC may include a silver-based conductive layer, at least partially protected by a zirconium oxide overcoat. Such TCCs may be provided in connection with monolithic or multi-substrate arrangements in different example embodiments. Certain example embodiments may involve “active” modes, where a silver-based layer in the TCC may receive a voltage, e.g., to reduce the likelihood of frosting, freezing, fogging, condensation, and/or the like, on the glass substrate that supports the TCC.
1 . A method of making an article for a refrigeration or freezer unit, the method comprising:
providing first and second substantially parallel and spaced apart glass substrates, the first substrate being provided for an interior side of the article and the second substrate being provided for an exterior side of the article;
sputter-depositing one or more transparent conductive coatings (TCCs), respectively, on one or more major surfaces of the first and/or second substrates; and
thermally tempering at least the first and second substrates,
wherein each said TCC is silver-based and includes a zirconium oxide protective overcoat.
2 . The method of claim 1 , wherein:
each said TCC comprises:
a first barrier layer of silicon nitride provided on the second substrate,
a first nickel chromium inclusive contact layer provided on the first barrier layer,
a silver-inclusive conductive layer provided on the first contact layer,
a second nickel chromium inclusive contact layer provided on the conductive layer, and
a second barrier layer of silicon nitride provided on the second contact layer, and
the protective overcoat is provided on the second contact layer.
3 . The method of claim 2 , wherein each said TCC has a sheet resistance of about 4 ohms/square.
4 . The method of claim 2 , wherein each said TCC has a sheet resistance of about 5 ohms/square.
5 . The method of claim 2 , wherein each said TCC has a sheet resistance of 3-15 ohms/square.
6 . The method of claim 2 , wherein the first and/or second barrier layer(s) is/are doped with aluminum.
7 . The method of claim 2 , wherein each said contact layer is about 5-20 angstroms thick.
8 . The method of claim 7 , wherein the silver-inclusive conductive layer is about 3-20 nm thick.
9 . The method of claim 1 , further comprising electrically connecting each said TCC to a power source via at least one bus bar.
10 . The method of claim 9 , wherein the power source, in operation, is configured to provide a voltage to the TCC to reduce the likelihood of frosting, freezing, fogging, and/or condensation in or on the article.
11 . The method of claim 1 , wherein the article is a door for the refrigeration or freezer unit.
12 . The method of claim 1 , further comprising providing at least two TCCs on major surfaces of the first and/or second substrates.
13 . A method of making a refrigeration or freezer unit, the method comprising:
making an article according to the method of claim 1 ; and
building the article into the unit.
14 . A method of making an article for a refrigeration or freezer unit, the method comprising:
providing a glass substrate;
sputter-depositing one or more transparent conductive coatings (TCCs) on one or more respective major surfaces of the substrate;
thermally tempering at least the substrate,
wherein each said TCC comprises:
a first barrier layer of silicon nitride provided on the second substrate,
a first nickel chromium inclusive contact layer provided on the first barrier layer,
a silver-inclusive conductive layer provided on the first contact layer,
a second nickel chromium inclusive contact layer provided on the conductive layer, and
a second barrier layer of silicon nitride provided on the second contact layer, and
a protective overcoat comprising zirconium oxide provided on the second contact layer, and
wherein each said TCC has a sheet resistance between about 3-15 ohms/square.
15 . The method of claim 14 , wherein the first and/or second barrier layer(s) is/are doped with aluminum.
16 . The method of claim 14 , wherein each said contact layer is about 5-20 angstroms thick, and wherein the silver-inclusive conductive layer is about 3-20 nm thick.
17 . The method of claim 14 , further comprising electrically connecting each said TCC to a power source via at least one bus bar.
18 . An assembly for a refrigeration or freezer unit, comprising:
first and second substantially parallel and spaced apart glass substrates;
at least one sputter-deposited transparent conductive coating (TCC), each said TCC being supported by one major surface of the first or second substrate;
wherein each said TCC comprises:
a first barrier layer of silicon nitride provided on the second substrate,
a first nickel chromium inclusive contact layer provided on the first barrier layer,
a silver-inclusive conductive layer provided on the first contact layer,
a second nickel chromium inclusive contact layer provided on the conductive layer,
a second barrier layer of silicon nitride provided on the second contact layer, and
a zirconium oxide protective overcoat provided on the second contact layer, and
wherein each said TCC has a sheet resistance of about 3-15 ohms/square.
19 . The assembly of claim 18 , wherein the first and/or second barrier layer(s) is/are doped with aluminum.
20 . The assembly of claim 18 , wherein the first and second substrates have a visible transmission of at least 50%.
21 . The assembly of claim 18 , wherein each said contact layer is about 5-20 angstroms thick, and
wherein the silver-inclusive conductive layer is about 3-20 nm thick.
22 . The assembly of claim 18 , further comprising one or more contacts in electrical connection with (1) each said TCC, respectively, and (2) at least one bus bar.
23 . The assembly of claim 22 , further comprising a seal between the first and second substrates around edges thereof.
24 . The assembly of claim 23 , wherein a cavity between the first and second substrates is filled with an inert gas.
25 . A refrigeration or freezer unit, comprising the assembly of claim 18 .
26 . An assembly for a refrigeration or freezer unit, comprising:
a glass substrate;
at least one sputter-deposited transparent conductive coating (TCC), each said TCC being supported by one major surface of the substrate;
wherein each said TCC comprises:
a first barrier layer of silicon nitride provided on the second substrate,
a first nickel chromium inclusive contact layer provided on the first barrier layer,
a silver-inclusive conductive layer provided on the first contact layer,
a second nickel chromium inclusive contact layer provided on the conductive layer,
a second barrier layer of silicon nitride provided on the second contact layer, and
a zirconium oxide protective overcoat provided on the second contact layer, and
wherein each said TCC has a sheet resistance of about 3-15 ohms/square.
27 . The assembly of claim 26 , wherein the first and/or second barrier layer(s) is/are doped with aluminum.
28 . The assembly of claim 27 , wherein each said contact layer is about 5-20 angstroms thick, and wherein the silver-inclusive conductive layer is about 3-20 nm thick.
29 . The assembly of claim 26 , further comprising one or more contacts in electrical connection with (1) each said TCC, respectively, and (2) at least one bus bar.
30 . A refrigeration or freezer unit, comprising the assembly of claim 26 .
31 . A method of making a coated article, the method comprising:
providing a glass substrate having at least one major surface to be coated; and
sputtering, on the glass substrate, a transparent conductive coating (TCC) comprising, in order from nearest to farthest from the glass substrate:
a first barrier layer of silicon nitride,
a first nickel chromium inclusive contact layer provided on the first barrier layer,
a silver-inclusive conductive layer provided on the first contact layer,
a second nickel chromium inclusive contact layer provided on the conductive layer,
a second barrier layer of silicon nitride provided on the second contact layer, and
a zirconium oxide protective overcoat provided on the second contact layer,
wherein each said contact layer is about 5-20 angstroms thick, and
wherein the silver-inclusive conductive layer is about 3-20 nm thick, causing the TCC to have a sheet resistance of about 3-15 ohms/square.
32 . A method of making a horizontally oriented refrigerator/freezer unit, the method comprising:
providing a coated article according to the method of claim 31 ; and
building the coated article into the horizontally oriented refrigerator/freezer unit as a door or window.