Method of making coated article including ion beam treatment of metal oxide protective film

Descriptive Report of the Invention Patent for "METHOD OF PRODUCING A COATED ARTICLE INCLUDING ION BEAM TREATMENT OF A METAL OXIDE PROTECTIVE FILM".

This application is a continuation in part (CIP) of U.S. Serial No. 11/699,080, filed January 29, 2007, and a continuation in part of 11/798,920, filed May 17, 2007, the full descriptions of which are thereby incorporated herein by reference.

The present invention relates to a method of producing heat-treated (HT) coated articles to be used in shower applications, window applications, tabletop applications, or any other suitable applications. For example, certain embodiments of this invention relate to a method of producing a coated article including a heat treatment step of a glass substrate coated with at least one layer comprising diamond-like carbon (DLC) and a protective film extending therefrom. In certain exemplary embodiments, the protective film may include one or both of (a) an oxygen-blocking or barrier layer, and (b) a release layer. In certain exemplary embodiments, the protective film (e.g., of or including zinc oxide) is ion beam treated so as to implant carbon (C) ions into it in order to improve the corrosion resistance of the coated article (i.e., to increase its service life) before heat treatment. Then and/or during heat treatment (e.g., thermal quenching, or similar) the protective film may be wholly or partially removed. Other embodiments of this invention relate to pre-HT coated articles, or post-HT coated articles, or methods of producing them.

BACKGROUND OF THE INVENTION

Coated articles such as transparent shower doors and IG window units are frequently heat treated (HT), such as being thermally tempered, for safety and/or strengthening purposes. For example, coated glass substrates for use in shower doors and/or window units are frequently heat treated at a high temperature(s) (e.g., at least around 580°C, more typically around 600 to 650°C for tempering purposes).

Diamond-like carbon (DLC) is sometimes known for its scratch-resistant properties. For example, different types of DLC are discussed in the following US Patents: 6,303,226; 6,303,225; 6,261,693; 6,338,901; 6,312,808; 6,280,834; 6,284,377; 6,335,086; 5,858,477; 5,635,245; 5,888,593; 5,135,808; 5,900,342; and 5,470,661, all of which are thereby incorporated herein by reference.

It would sometimes be desirable to provide a window unit or other glass article with a protective coating including DLC ​​in order to protect it from scratches and the like. Unfortunately, DLC tends to oxidize and burn at temperatures of approximately 380 to 400°C, as the heat treatment is typically conducted in an atmosphere including oxygen. Therefore, it will be appreciated that DLC as a protective coating cannot withstand heat treatments (HT) at the extremely high temperatures described above that are frequently required in the manufacture of vehicle windows, IG window units, glass tabletops, and/or the like.

Consequently, those skilled in the art will appreciate that a need in the art exists for a method of providing heat-treated (HT) coated articles with a protective coating (one or more layers) comprising DLC. A need for corresponding coated articles, both heat-treated and pre-HT, also exists.

In this particular case, U.S. Patent Application Serial No. 11/798,920 (incorporated herein by reference) describes a method for producing a coated article including a heat treatment step of a glass substrate coated with at least one layer comprising diamond-like carbon (DLC) and a protective zinc oxide film thereon. In certain exemplary embodiments, the protective film may be of or include both (a) an oxygen-blocking or barrier layer, and (b) a release layer. Subsequently and/or during heat treatment (e.g., thermal tempering, or similar) the zinc oxide-based protective film may be wholly or partially removed.

Unfortunately, the pre-HT service life and/or stability of 11/798.920 coated articles are limited. For example, the zinc oxide-based protective film has been found to be susceptible to corrosion before heat treatment (after heat treatment, the protective film often disappears). Samples stored in moderately humid environments begin to stain (when viewed from the side of the glass), suggesting that over time moisture is penetrating the zinc oxide-based protective film and reaching the DLC. Also, the 11/798.920 films as deposited are unable to pass the one-hour test environment under high heat and high humidity condensation (50°C/95°RH).

Consequently, it will be appreciated that there is a need in the art to improve the service life and/or stability of coated articles such as those of 11/798.920 so that they are less prone to staining before heat treatment (HT).

BRIEF SUMMARY OF EXAMPLES OF THE INVENTION

Certain exemplary embodiments of this invention relate to a method of producing a heat-treated (HT) coated article to be used in shower door applications, window applications, tabletop applications, or any other suitable application. For example, certain embodiments of this invention relate to a method of producing a coated article including a heat treatment step of a glass substrate coated with at least one layer comprising diamond-like carbon (DLC) and a protective film extending therefrom. In certain further exemplary embodiments, the protective film may be of or include both (a) an oxygen-blocking or barrier layer, and (b) a release layer. In certain exemplary embodiments, the protective film (e.g., of or including zinc oxide) is treated with an ion beam to implant carbon (C) ions in order to improve the corrosion resistance of the coated article (i.e., increase its service life) before heat treatment. Then, and/or during heat treatment (e.g., thermal quenching, or similar), the protective film may be wholly or partially removed. Certain exemplary embodiments of this invention relate to articles coated with pre-HT, or articles coated with post-HT, or methods of producing them.

In certain exemplary embodiments of this invention, a method is provided for producing a heat-treated coated article, the method comprising: providing a glass substrate; forming at least one layer comprising diamond-like carbon (DLC) on the glass substrate; formation of a protective film comprising zinc oxide on the glass substrate over at least the layer comprising DLC, ion beam treatment of the protective film comprising zinc oxide with at least carbon ions; heat treatment of the glass substrate with the layer comprising DLC ​​and the protective film such that during the heat treatment the protective film prevents significant burning of the layer comprising DLC, wherein the heat treatment comprises heating the glass substrate to temperature(s) sufficient for thermal tempering, heat strengthening, and/or heat bending; and exposure of the protective film to a release liquid and removal of at least part of the protective film during and/or after said heat treatment.

In other exemplary embodiments of this invention, a method for producing a heat-treated coated article is provided, the method comprising: providing a glass substrate; forming at least one layer comprising carbon on the glass substrate; forming a protective film comprising at least one metal oxide on the glass substrate over at least the layer comprising carbon; ion beam treatment of the protective film with at least carbon ions; heat treatment of the glass substrate with the layer comprising carbon and the protective film such that during the heat treatment the protective film prevents significant burning of the layer comprising carbon, wherein the heat treatment comprises heating the glass substrate to temperature(s) sufficient for thermal tempering, heat strengthening and/or heat bending.

In further exemplary embodiments of this invention, a coated article is provided comprising: a glass substrate; a layer comprising diamond-like carbon (DLC) on the glass substrate; a protective film comprising zinc oxide on the glass substrate over at least the layer comprising DLC; a layer or portion of a layer comprising zinc oxycarbide provided in a surface portion of the protective film comprising zinc oxide, such that the protective film comprising zinc oxide is graduated, continuously or discontinuously, with respect to carbon content so as to have more carbon at a location in the protective film distant from the glass substrate than at a location in the protective film closer to the glass substrate.

In other exemplary embodiments of this invention, a method for producing a heat-treated coated article is provided, the method comprising: providing a glass substrate; forming at least one layer comprising diamond-like carbon (DLC) on the glass substrate; formation of a protective film comprising zinc oxide on the glass substrate over at least the layer comprising DLC, wherein said protective film comprising zinc oxide is formed using at least one crackling target comprising zinc that is crackled in an atmosphere including at least carbon dioxide; heat treatment of the glass substrate with the layer comprising DLC ​​and the protective film such that during the heat treatment the protective film prevents significant burning of the layer comprising DLC, wherein the heat treatment comprises heating the glass substrate to temperature(s) sufficient for thermal tempering, heat strengthening, and/or heat bending; and exposure of the protective film to a release liquid and removal of at least part of the protective film during and/or after said heat treatment. It is possible that ion beam treatment may not be necessary in this embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS___

Figure 1 is a schematic cross-sectional view of a coated article, before and after heat treatment, according to an exemplary embodiment of this invention.

Figure 2 is a schematic cross-sectional view of a coated article, before and after heat treatment, according to another exemplary embodiment of this invention.

Figure 3 is a schematic cross-sectional view of a coated article, before and after heat treatment, according to another exemplary embodiment of this invention.

Figure 4 is a schematic cross-sectional view of a coated article, before and after heat treatment, according to another exemplary embodiment of this invention.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS OF THE INVENTION

Referring now more specifically to the accompanying drawings in which similar numerical references indicate similar parts through various views.

Certain exemplary embodiments of this invention relate to methods of producing coated articles that may use heat treatment (HT), wherein the coated article includes a coating (one or more layers) including diamond-like carbon (DLC). In certain examples, the HT may involve heating on a glass substrate support, with the DLC on the same, to a temperature(s) of 550 to 800°C, more preferably 580 to 800°C (which is well above the burning temperature of DLC). In particular, certain exemplary embodiments of this invention relate to a technique for enabling DLC ​​to withstand such HT without burning significantly during the same. In certain embodiments, a sacrificial protective film (e.g., of or including one or more layers comprising zinc oxide, or the like) is formed on the glass substrate over the DLC so as to reduce the likelihood of DLC burning during HT. In certain exemplary embodiments, the protective film (e.g., of or including zinc oxide) is treated with an ion beam in order to implant carbon (C) ions into it. It has surprisingly been found that this carbon implantation in the protective film improves the corrosion resistance of the coated article (i.e., increases its service life) before heat treatment. Subsequently and/or during heat treatment (e.g., thermal tempering, or similar), the protective film may be fully or partially removed. In this way, most (if not all) of the DLC remains on the glass substrate and does not burn during heat treatment. Following heat treatment, the sacrificial protective film (which may include one or more layers) may or may not be removed in different embodiments of this invention.

In certain example embodiments, the sacrificial protective film may be of or include both (a) an oxygen-blocking or barrier layer, and (b) a release layer. An example advantage of using distinct and different oxygen-blocking and oxygen-release layers in film 17 is that each layer (17a and 17b) can be optimized for its intended function. Consequently, the optimized performance of the sacrificial film 17 can be improved and it can be produced thinner if desired. Ion treatment of the protective film causes a thin layer of or including zinc oxycarbide 17c to form at least on a surface area of ​​the film 17. In certain exemplary embodiments, following the HT, the DLC inclusive layer protects against abrasion and corrosion, and against mineral adhesion in hard water (e.g., it has good hard water cleanup). In exemplary embodiments alternatively, the protective film 17 (e.g., of or including zinc oxide which may or may not be doped with Al or similar) may be a simple layer which may or may not be oxidation-graded.

Figure 1 is a schematic cross-sectional view of a coated article, before and after heat treatment, according to an exemplary embodiment of this invention. Typically, the coated article on the left side of Figure 1 exists during a manufacturing stage before heat treatment (HT), but it also exists post-HT in certain examples. The coated article shown in Figure 1 includes a glass substrate 1, an inclusive DLC layer 11, and a sacrificial protective film 17 which may include one or more layers. In certain exemplary embodiments, the protective film 17 includes first and second layers 17a and 17b which may be of the same or different materials, and includes an inclusive zinc oxycarbide layer or a layer portion 17c resulting from ion beam treatment. The glass substrate 1 is typically made of, or includes, soda-lime-silica glass, although other types of glass may be used in certain examples.

The inclusive layer of DLC 11 can be about 5 to 1,000 angstroms (A) thick in certain exemplary embodiments of this invention, more preferably 10-300 A thick, and most preferably 20 to 65 A thick, possibly about 25-50 A thick, with an exemplary thickness being about 30 angstroms. In certain exemplary embodiments of this invention, the DLC 11 layer may have an average hardness of at least about 10 GPa, more preferably at least about 20 GPa, and most preferably about 2090 GPa. Such hardness makes the layer(s) 11 resistant to scratching, certain solvents, and/or the like. Layer 11 may, in certain exemplary embodiments, be of or include a special type of DLC known as highly tetrahedral amorphous carbon (t-aC), and may be hydrogenated (t-aC:H) in certain embodiments. In certain hydrogenated embodiments, the t-aC type or any other suitable type of DLC may include from 1 to 30% hydrogen, more preferably from 5-20% H, and most preferably from 10-20% H. This t-aC type of DLC includes more sp bonds.³ carbon-carbon (C--C) bonds more than sp bonds² carbon-carbon (C--C). In certain example embodiments, at least about 30% or 50% of the carbon-carbon bonds in the DLC 11 layer may be sp bonds.³ carbon-carbon (C-C), more preferably at least about 60% of the carbon-carbon bonds in the 11th shell may be sp bonds.³ carbon-carbon (C-C) bonds, and, more preferably, at least about 70% of the carbon-carbon bonds in the 11th shell may be sp bonds.³ carbon-carbon (C-C). In certain exemplary embodiments of this invention, the DLC may have an average density of at least about 2.4 g/cm³.³, more preferably at least about 2.7 gm/cm. Example linear ion beam sources that can be used to deposit inclusive DLC layer 11 on substrate 1 include any of those in any of US Patent Nos. 6,261,693, 6,002,208, 6,335,086, or 6,303,225 (all incorporated herein by reference). When using an ion beam source to deposit layer(s) 11, hydrocarbon feed stock gas(gases) (e.g., C₂H₂), HMDSO, or any other suitable gas, may be used in the ion beam source so as to cause the source to emit an ion beam towards substrate 1 for layer formation 11. It is noted that the hardness and/or density of layer(s) 11 may be adjusted by varying the ion energy of the deposition apparatus.

The DLC 11 layer allows the coated article to be more scratch-resistant than if DLC 11 were not provided. It is noted that while layer 11 is on the glass substrate 1 in certain embodiments of this invention, additional layer(s) may or may not be under layer 11 between substrate 1 and layer 11 in certain exemplary embodiments of this invention. Thus, the phrase "in the substrate," as used here, is not limited to being in direct contact with the substrate, as other layer(s) may also be provided between them.

For example, and without limitation, layer 11 of or including DLC ​​may be any of the layers including DLC ​​of any of the US patents Nos. 6,592,993; 6,592,992; 6,531,182; 6,461,731; 6,447,891; 6,303,226; 6,303,225; 6,261,693; 6,338,901; 6,312,808; 6,280,834;

6.284.377; 6.335.086; 5.858.477; 5.635.245; 5.888.593; 5.135.808;

5,900,342; or 5,470,661 (all these patents being, therefore, incorporated herein by reference), or alternatively, they may be any other suitable type of layer, including DLC. The DLC layer 11 may be hydrophobic (high contact angle), hydrophilic (low contact angle), or none, in different embodiments of this invention. DLC 11 may or may not include about 5-30% Si, more preferably about 5-25% Si, and possibly about 10-20% Si in certain exemplary embodiments of this invention. Hydrogen may also be provided in the DLC in certain examples.

The sacrificial protective film 17 is provided to protect the DLC layer 11 during HTX. If film 17 were not provided, the DLC 11 would oxidize significantly during HT and burning, thus rendering the final product defenseless against scratching. However, the presence of sacrificial protective film 17 prevents or reduces the amount of oxygen that can reach the DLC 11 during HT from the surrounding atmosphere, thus preventing the DLC from oxidizing significantly during HT. As a result, after HT, the inclusive DLC layer 11 remains on the glass substrate 1 so as to provide scratch and/or similar resistance. In certain exemplary embodiments, the protective film 17 includes both an oxygen blocking or barrier layer 17a, and a release layer 17b.

It has been surprisingly found that the use of zinc and/or zinc oxide in the sacrificial protective film 17 is/are especially beneficial with regard to reducing and/or preventing oxygen diffusion in the DLC during HT. In Figure 1 of the exemplary embodiment of this invention, the protective film 17 includes a first inclusive layer of zinc 17a and a second inclusive layer of zinc oxide 17b. The first inclusive zinc layer 17a may be substantially metallic, or stoichiometric zinc oxide in different exemplary embodiments of this invention; whereby the second inclusive zinc oxide layer 17b may be of or including zinc oxide in certain exemplary embodiments of this invention. In certain exemplary embodiments, layer 17a is more metallic than layer 17b. In other words, layer 17b contains more oxygen than layer 17a. Thus, layer 17a is able to function as a release layer, while layer 17b is able to function as an oxygen blocking or barrier layer, along with the zinc oxycarbide layer 17c. An oxygen blocking layer or barrier layer means that the layer blocks significant amounts of oxygen from reaching the DLC during HT.

In certain exemplary embodiments of this invention, layer 17a may be of or include ZnO._y and layer 17b may be of or include ZnO_x, where x>y (that is, layer 17b contains more oxygen than layer 17a). Furthermore, in certain exemplary embodiments of this invention, y is from about 0 to 0.9, more preferably from about 0.1 to 0.9, even more preferably from about 0.1 to 0.8, and possibly from about 0.1 to 0.7. Sometimes, in certain exemplary embodiments of this invention, x is greater than y, ex is from about 0.3 to 1.0, more preferably from about 0.3 to 0.99, even more preferably from about 0.5 to 0.95, and possibly from about 0.6 to 0.90. Thus, it will be appreciated that in certain examples, both layers 17a and 17b may be of or include zinc oxide, and both layers 17a and 17b may be stoichiometric.

Advantageously, it was found that the use of zinc oxide layer 17a, which is more metallic than zinc oxide layer 17b (in which 17c is formed), surprisingly allows for more efficient and easier removal of the protective film 17 during and/or after heat treatment (HT). In other words, layer 17a is a release layer. Different compositions of inclusive zinc oxide layers 17a and 17b are used to cause different stresses in layers 17a and 17b, which stresses are manipulated in order to allow film 17 to be more easily removed during and/or after HT. In particular, layer 17a, based on more metallic zinc oxide, can be considered a release layer to allow film 17 to be easily removed from the DLC or substrate during and/or after HT due to its reduced or non-existent oxygen content, whereas layer 17b, based on less metallic (and more oxidized) zinc oxide, can be considered an oxygen-blocking or barrier layer that reduces or prevents the DLC from burning and/or oxidizing during HT. Zinc oxide is an advantageous material for film 17 because it can be easily removed (e.g., using water and/or vinegar) during and/or after HT in a non-toxic manner.

As noted above, one or both of layers 17a and 17b, when containing or including zinc and/or zinc oxide, may be substoichiometric. This is advantageous for the proposed method of obtaining oxygen during HT. If the zinc oxide of the total layer 17 is highly oxidized (i.e., fully stoichiometric) prior to HT, then oxygen can diffuse through the zinc oxide. However, the substoichiometric nature of layer(s) 17a and/or 17b allows the zinc to obtain oxygen during HT, so that at least layer 17a (and possibly layer 17b) does not burn during HT. It is noted that layer 17b based on top zinc oxide and/or zinc oxycarbide (or zinc aluminum oxycarbide 17c) may or may not burn (fully or partially) during HT in embodiments of examples other than this invention. It is noted that another advantage of the stoichiometric zinc oxide example (compared to fully stoichiometric zinc oxide) is that it can be deposited (e.g., via cracking or similar) more rapidly. One or both of layers 17a, 17b can be deposited by cracking in a stoichiometric form, in any suitable manner; for example, by varying the oxygen gas flow in the cracking chamber(s). For example, as a non-limiting example, layer 17a can be deposited by decrepitation using 10 ml/kW (relative to the oxygen gas flow rate), so layer 17b can be deposited by decrepitation using 12 ml/kW (with the remainder of the gas being Ar or similar) in the examples.

It is noted that one or more of the inclusive zinc oxide layers 17a, 17b and 17c may be doped with other materials such as Al, N, Zr, Ni, Fe, Cr, Ti, Mg, mixtures thereof, or similar materials, in certain exemplary embodiments of this invention.

In certain exemplary embodiments of this invention, the release layer 17a (e.g., of zinc or stoichiometric zinc oxide) can be deposited (e.g., via crepitation) so as to be about 50-20,000 Å thick, more preferably about 50-3,000 Å thick, even more preferably about 100-1,000 Å thick, with an exemplary thickness being about 100-300 Å. In certain embodiments, an inclusive layer of zinc oxide 17b can be deposited (e.g., via decrepitation) so as to be approximately 20013

10,000 Å thick, more preferably about 500-5,000 Å thick, more preferably about 1,000-3,000 Å thick, with an example thickness being about 2,000 Å. In certain exemplary embodiments, the zinc oxycarbide or layer, including zinc aluminum oxycarbide, or layer portion 17c, may be at least about 50 Å thick in certain exemplary embodiments (e.g., 50-500 Å thick), more preferably at least about 100 Å (e.g., 100-500 Å thick), 150 Å (e.g., 150-400 Å thick), or 200 Å thick (e.g., 200-400 Å thick). The more metallic layer 17a may be thicker than the less metallic layer 17b (17b includes 17c in this particular) in certain exemplary embodiments of this invention; layer 17a may be at least twice as thick as layer 17b in certain examples prior to HT. A preferred thickness of 17 total sacrificial film in certain exemplary embodiments is less than about 10,000 A, more preferably less than about 3,000 A, and most preferably less than about 1,000 A.

Figure 2 illustrates another exemplary embodiment of this invention. The embodiment in Figure 2 is the same as the embodiment in Figure 1 discussed above, except that in the embodiment in Figure 2 a barrier layer 6 is provided between the glass substrate 1 and the inclusive DLC layer 11. The barrier layer 6 may be a dielectric in certain exemplary embodiments of this invention. Optional barrier layer 6 is for preventing or reducing oxygen and/or sodium (Na) migration from glass 1 into DLC 11 during HT. In this particular case, such optional barrier layer 6 can improve the overall optical characteristics of the post-HT coated article. Barrier layer 6 may be of or include silicon oxide, silicon nitride, silicon oxynitride, and/or similar materials, although other barrier materials may also be used. Barrier layer 6 is formed on the glass substrate 1 via crackling, or via any other suitable technique. Barrier layer 6 can be about 10 to 1,000 Å thick in certain exemplary embodiments, more preferably 50 to 500 Å thick, and most preferably 50 to 200 Å thick. It is noted that a barrier layer 6 may also be provided in other exemplary embodiments of this invention, for example in any of Figures 4-7 if desired between the DLC 11 and the glass substrate 1.

Figure 3 illustrates another exemplary embodiment of this invention. The embodiment in Figure 3 is the same as the embodiment in Figure 1 (or even the embodiment in Figure 2 if barrier layer 6 is used, which may be the case in the embodiment in Figure 3), except that instead of two discrete layers 17a and 17b, the protective film 17 is made of a layer that is graduated by oxidation (continuously or non-continuously) through its thickness. In the embodiment of Figure 3, film 17 is provided in such a way that film 17 includes more oxygen at a location distant from the DLC 11 layer than at another location in the film closer to the DLC 11 layer. It is noted that film 17 in the embodiments of Figures 1-2 can also be considered oxidation-graded because the total film 17 is more oxidized in layer 17b distant from DLC 11 than in layer 17a closer to DLC 11. However, in the embodiment of Figure 3, it is also possible that continuous or substantially continuous oxidation gradation may occur through the film 17 completely or substantially completely in certain examples.

In each of the embodiments of Figures 1-3, the protective film 17 (e.g., of or including zinc oxide) can be treated with an ion beam so as to implant at least carbon (C) into the film 17, at least in a surface area thereof. It has surprisingly been found that this carbon implantation into the protective film improves the corrosion resistance of the coated article (i.e., increases its service life) before heat treatment. Ion beam treatment can be carried out using one or more ion sources 18. Gas such as acetylene (C2H2), carbon dioxide, or similar can be used in the ion source 18 during such ion source treatment in order to cause carbon ions to be directed towards eae in the film 17. In certain exemplary embodiments, the carbon can be implanted to at least about 50 Å below the surface of film 17, more preferably to at least about 100 Å, 150 Å, or 200 Å below the surface of film 17. The ion beam treatment causes at least some zinc oxycarbide to form in at least one surface area of ​​film 17. Thus, the zinc oxycarbide 17c inclusive layer can be at least about 50 Å thick in certain exemplary embodiments, more preferably at least about 100 Å, 150 Å, or 200 Å thick. Because zinc oxycarbide is hermetically adherent and relatively insoluble, the film 17 becomes more corrosion-resistant and more durable, thereby extending its pre-HT service life. Samples treated using carbon dioxide have been found to have an improved shelf life compared to samples treated using only oxygen.

In different embodiments of this invention, the ion beam treatment of film 17 can be performed: (a) after the film 17 has been deposited by desiccation, and/or (b) while the film 17 is being deposited by desiccation. The first case may be referred to as peening, while the latter case may be referred to as ion beam assisted deposition (IBAD) in certain examples. IBAD-type ion beam treatment is performed simultaneously with crepitation, so that the ion beam is being used to treat film 17 as it is being deposited by crepitation.

An example of ion beam treatment according to a type of peening (a) of ion beam treatment for film 17 can be described as follows. A film 17 (including one or both of 17a, 17b) (e.g., ZnO_x) is deposited by crackling on the glass substrate 1. The crackled zinc oxide film 17 may or may not be doped with other elements (e.g., Al) in different embodiments of this invention. After the ZnO_xIf the inclusive film 17 has been crackled onto substrate 1 over DLC 11, the coated article is moved relative to at least one ion source 18 so as to be in a position for crackling. At least one gas including carbon (e.g., a dehydrocarbon gas such as C₂H₂ or similar) is fed through or used in ion source 18 such that the ion source causes an ion source including at least carbon (C) ions to be emitted towards the ZnO film._x 17. The C ions in the ion beam are provided with sufficient energy so that they can implant into the film, including ZnO._x as shown in Figures 1-3. It is noted that the ion beam from source 18 can be focused, diffused, or collimated in the different embodiments of this invention.

Implantation of C/atom ions in the film including 17 of ZnO_x The crackling action causes a layer comprising zinc oxycarbide 17c to form at least near the surface of the film, as shown in Figures 1-3. This implantation of C/atom ions into film 17 causes the corrosion resistance of the resulting film 17 to improve significantly compared to that of a film 17 before the C/atom ions were implanted.

When implanted in the ZnO film_x 17, in certain examples the carbon ions have sufficient ion energy to eliminate oxygen (O) from ZnO molecules._x in order to enable a substantially continuous layer or portion of a layer comprising zinc oxycarbide 17c to form near a surface of the previously crepitated layer as shown in Figures 1-3. In certain exemplary embodiments, the zinc oxycarbide 17c layer may be characterized at least in part by ZnO_xW_y, where x/y is from 0.5 to 1.5.

A relatively high voltage is required at the ion source 18 in order to provide sufficient energy for the carbon ions in the beam from the ion source to: (a) implant in the ZnO film_x crackling 17, (b) elimination of oxygen from ZnO molecules_x, and (c) carry out (a) and (b) to a sufficient extent so that a substantially continuous layer of zinc oxycarbide 17c can be formed. In order to achieve sufficient energy in this particular case, according to certain exemplary embodiments of this invention, the ion source 18 uses an anode-cathode voltage of at least about 800 V, more preferably at least about 1,500 V, even more preferably at least about 2,000 V, and even more preferably at least about 2,500 V. A source voltage of at least about 3,500 V may also be used in certain examples. The aforementioned voltage (or acceleration voltage) used in the ion source 18 to cause implantation of C ions/atoms in the film 17 is the voltage between the anode and cathode of the ion source. As is known in the art, ion energy is related to this anode/cathode voltage, but is different. The ion energy of a molecular fragment is half (1/2) the acceleration voltage for molecular acetylene (C₂H₂), for example. Thus, the ion energy of a molecular fragment, given a voltage of 2,000 V, would be 2,000/2 = 1,000 V. Furthermore, in the case of C ions formed from acetylene (C₂H₂In the ion source, where C is used as a feedstock gas, there are two carbon atoms per molecular fragment. Therefore, the energy per carbon ion is the molecular fragment ion energy divided by 2.₂H₂ It is used as the feedstock gas to form C-ions in the beam. In other words, for the sake of example only, in the case where C-ions are formed using C-₂H₂ As the feedstock gas in the ion source, the ion source voltages (i.e., at least about 800 V, 1,500 V, 2,000 V and/or 2,500 V as explained above) translate into ion energies of at least about 200 eV per C ion, more preferably at least about 375 eV per C ion, even more preferably at least about 500 eV per C ion, and even more preferably at least about 625 eV per C ion. If a very low ion energy (or voltage in the ion source) is used, C-ion implantation and/or formation of a continuous layer comprising titanium oxycarbide cannot be achieved.

It will be recognized that when a hydrocarbon gas such as C₂H₂ It is used as the feedstock gas in source 18, the ions in the resulting beam will include both C ions and H ions. Thus, the zinc oxycarbide layer or layer portion 17c can be doped with H (in addition to Al or similar) in certain embodiments of this invention. In certain exemplary embodiments, layer 17c may include from 0 to 20% H, more preferably from about 1 to 18% H, and even more preferably from about 5 to 15% H.

In certain embodiments of this invention, C ions are implanted deep enough into the ZnO film._x crepitated film 17 so as to enable a substantially continuous layer comprising zinc oxycarbide 17c to form at least near a top portion thereof. In certain exemplary embodiments, at least some C ions (and/or C atoms) are implanted in the crepitated film 17 at a depth d” of at least 25 Å below the top surface of the crepitated film 17 (more preferably at least 50 Å, even more preferably at least 100 Å). Insufficient implementation can contribute to a lack of increased durability, or similar issues, or excessively rapid wear.

In certain exemplary embodiments of this invention, the ion source 18 can be operated so as to emit only sufficient C ions towards the film 17 so as to cause C ion/atom implantation in the film 17 as shown in Figures 1-3, but not cause an amorphous DLC layer (e.g., ta-C or ta-C:H) to form on the zinc oxycarbide layer 17c. Alternatively, in other embodiments of this invention, source 18 is operated so as to cause a thin layer (not shown) comprising amorphous DLC (e.g., ta-C or ta-C:H) to form on the zinc oxycarbide layer 17c. Exemplary features of such DLC layers are discussed in U.S. Patent No. 6,261,693, which is hereby incorporated by reference. This thin DLC layer (not shown) can be about 1-30 Å thick in certain example embodiments, more preferably about 1-20 Å thick. It is noted that other layers may also be provided over the oxycarbide in certain examples. Furthermore, this very thin inclusive DLC layer may in certain embodiments be sacrificial, wherein it is designed so that it may wear away (i.e., disappear) over time, especially during HT. Thus, for example, such a thin layer comprising DLC ​​can be used to protect the coated article from scratches or similar damage during loading, processing, or similar, and then wear off over time (or burn during HT). Optionally, this extending layer comprising DLC ​​(not shown) can be even thicker than 30 Å in certain examples. Such extending layer(s) including DLC ​​shown herein may include a large number of sp bonds.³ carbon-carbon (for example, at least 40% of the C-C bonds in the layer may be such bonds, more preferably at least 50%), may or may not be hydrogenated (for example, from about 1-25% H, more preferably from about 3-18% H) or include other dopants in different embodiments of this invention, and/or may have a density of at least 2.4 gms/cm³ in certain examples.

The ion sources 18 examples that can be used for film ion beam treatment 17 are described in US Patents Nos. 6,002,208, 7,052,585, and 2005/0258029, all of which are thereby incorporated herein by reference.

An example process for manufacturing a coated article will now be described, with reference to Figures 1-3. Initially, the glass substrate 1 is provided, and at least one barrier layer 6 (e.g., silicon oxide, silicon nitride, silicon oxynitride, or similar) may optionally be crackled onto a surface thereof. Optionally, a multilayer solar control coating (not shown) may be deposited (e.g., via crackling) on ​​the surface of the glass substrate 1 opposite the barrier layer 6. At least one layer 11 of or including DLC ​​is deposited (e.g., via ion beam deposition) on the glass substrate 1, over at least the optional barrier layer 6 if present. Then, the protective film 17, for example, including one or more layers (e.g., of or including zinc oxide), is deposited on substrate 1 over the inclusive DLC layer 11. The protective film 17 can be deposited via crackling, CVD, ion beam deposition, or any other suitable technique. The protective film 17 is then treated with an ion beam with at least γ- ions as discussed above. Optionally, a thin protective layer comprising DLC, silicon nitride, aluminum nitride, or aluminum silicon nitride (not shown), may be provided over film 17 prior to HT in certain examples, for proposed durability and/or oxygen barrier. As shown in Figures 1-3, the glass substrate 1 with films 6 (optional), 11 and 17 is then heat treated (HT) for proposed thermal tempering, heat bending, heat strengthening, and/or similar purposes. At least part of this HT can be conducted, for example, in an atmosphere including oxygen as known in the art at temperature(s) from 550 to 800°C, more preferably from 580 to 800°C (i.e., temperature(s) above the DLC burning temperature). The HT can last at least one minute, more preferably from 1-10 minutes, in certain non-limiting exemplary embodiments of this invention. During HT, the presence of protective film 17 protects layer 11, including DLC, from HT and prevents layer 11 from significantly oxidizing and/or burning due to significant oxidation during HT. While in some examples some of layer 11 may burn during HT, most if not all of layer 11, including DLC, remains on substrate 1 even after HT due to the presence of protective film 17. However, film 17 can be removed during and/or after HT. A significant advantage associated with the use of zinc and/or zinc oxide in film 17 is its ease of removal after HT. It has been found that when film 17 is made of zinc and/or zinc oxide, soluble in vinegar and/or water (possibly only water with no vinegar required in certain preferred embodiments), the application of vinegar and/or water allows portions of film 17 that remain after HT to be easily removed in a non-toxic manner. Again, in certain example embodiments, it is possible to remove zinc oxide with just water (no vinegar needed), which is advantageous from a cost and process standpoint. In certain examples, friction with such liquids can be especially beneficial in removing film 17 after HT when the coated article is still hot (for example, when film 17 is about 80-200°C, more preferably about 100-180°C; although film 17 removal can also occur at room temperature in certain exemplary embodiments). After film 17 has been removed, the remaining coated article is shown on the right side of Figures 1-3, and includes an outer layer comprising scratch-resistant DLC. The aforementioned processes are advantageous in that they provide a technique for allowing a coated article including an inclusive protective DLC layer 11 to be heat treated without the DLC layer 11 burning during such HT. In other words, it becomes possible to provide an inclusive protective DLC layer 11 on a heat-treated (e.g., thermally tempered) product in a commercially available manner.

Figure 4 is a schematic cross-sectional view of a method for producing a coated article according to another exemplary embodiment of this invention. No ion beam treatment of the layer or film 17 is required in this embodiment, although ion beam treatment may be used to treat film 17 after it has been deposited according to the embodiment of Figure 4. In the embodiment of Figure 4, one or more T-crackle targets (e.g., magnetron spin targets) of or including Zn or ZnO_x The film(s) 17 are used to deposit by decrepitation onto substrate 1 as the substrate moves in direction D, possibly over DLC 11. Film 17 may be of or include zinc oxide as in any of the embodiments discussed above with respect to Figures 1-3. In the embodiment of Figure 4, gas including carbon (for example, one or more of carbon dioxide, acetylene, or similar) is introduced into the crackling chambers so that the target(s) T is/are crackled in an atmosphere including carbon gas and possibly another gas such as oxygen gas and/or argon gas so as to deposit by crackling a film including zinc oxide 17. Due to the presence of carbon dioxide in the crackling chamber, the zinc oxide film 17 is deposited in a manner that includes carbon. In this embodiment, carbon can be provided throughout the thickness of the film 17 (or a layer thereof) in a substantially constant manner in certain exemplary embodiments.

It is also possible to deposit layer 17a using one or more T-crepitation targets (e.g., magnetron spin targets) of or including Zn or ZnO._x in an oxygen and/or argon atmosphere (no or little carbon), and then deposit the 17b layer using one or more T-crackle targets (e.g., magnetron spin targets of or including Zn or ZnO)._x in an atmosphere including carbon dioxide in addition to oxygen and/or argon as discussed above. In this particular case, film 17 would be graded, continuously or discontinuously, with respect to carbon content throughout the film.

The embodiment in Figure 4 is similar to the embodiments in Figure 1-3 in that the presence of carbon in film 17 causes zinc oxycarbide to be formed in film 17 (through all or only part of it, including on its top surface). This zinc oxycarbide in film 17 causes the corrosion resistance of the resulting film 17 to improve significantly compared to that of a zinc oxide film not including oxycarbide. After the formation of film 17 in the embodiment of Figure 4, the coated article can be heat treated (HT), and film 17 can be removed, as described above in conjunction with the embodiments of Figure 1-3.

According to certain exemplary embodiments of this invention, the coated articles herein lose no more than about 15% of their visible transmission due to HT, more preferably no more than about 10%. Furthermore, monolithic coated articles herein preferably have a visible transmission after HT of at least about 50%, more preferably at least about 60 or 75%.

In certain exemplary embodiments of this invention, Mg can replace or supplement Zn in the protective film 17.

While the invention has been described in conjunction with what are currently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not limited to the embodiments described, but, on the contrary, is intended to cover various equivalent modifications and arrangements included within the spirit and scope of the appended claims.