FR3131743A1 - Solar control and/or low-emission glazing - Google Patents

Abstract

The invention relates to a material comprising a substrate coated with a stack of layers comprising at least one silver-based functional metallic layer and at least two dielectric coatings, each dielectric coating comprising at least one dielectric layer, so that each functional metallic layer is arranged between two dielectric coatings, characterized in that the dielectric coating located above the functional metallic layer comprises: - a zinc-based layer located in contact with the functional layer having a thickness of between 0.3 and 3.0 n m, and - a layer based on titanium oxide located above and in contact with the layer based on zinc having a thickness greater than or equal to 3.0 nm.

Description

Solar control and/or low emissive glazing

The invention relates to a material comprising a transparent substrate coated with a functional coating capable of acting on solar radiation and/or infrared radiation. The invention also relates to glazing comprising these materials as well as the use of such materials to manufacture thermal insulation and/or solar protection glazing. In the remainder of the description, the term “functional” qualifying “functional coating” means “capable of acting on solar radiation and/or infrared radiation”.

These glazings can be used both to equip buildings and vehicles, in particular with a view to:
- reduce the air conditioning effort and/or prevent excessive overheating, so-called “solar control” glazing and/or
- reduce the quantity of energy dissipated to the outside, so-called “low emissive” glazing.

The functional silver-based metallic layers (or silver layers) have advantageous electrical conduction and reflection properties of infrared (IR) radiation, hence their use in so-called “solar control” glazing aimed at reducing the quantity of incoming solar energy and/or in so-called “low-emission” glazing aimed at reducing the quantity of energy dissipated to the outside of a building or vehicle.

These silver layers are deposited between coatings based on dielectric materials generally comprising several dielectric layers (hereinafter “dielectric coatings”) making it possible to adjust the optical properties of the stack. These dielectric layers also make it possible to protect the silver layer from chemical or mechanical attacks.

When we seek to develop solar control glazing, we seek to reduce the solar factor and increase light transmission and selectivity. When we seek to develop low-emissive glazing, we seek to reduce the emissivity and increase the solar factor. In all cases, we seek to minimize heat losses.

Emissivity and resistivity (or resistance) per square vary proportionately. Therefore, it is often possible to evaluate the emissivity of a material by evaluating its resistance per square.

The solar factor of the glazing “FS or g” corresponds to the ratio in % between the total energy entering the room through the glazing and the incident solar energy. The solar factor therefore measures the contribution of glazing to the heating of the “room”. The smaller the solar factor, the lower the solar gains.

Optical and electrical properties such as emissivity depend directly on the quality of the silver layers such as their crystalline state, their homogeneity as well as their environment. By “environment” we mean the nature of the layers near the silver layer and the surface roughness of the interfaces with these layers. Another way to reduce emissivity therefore consists of improving the quality of the silver layer by choosing a favorable environment.

To improve the quality of the functional silver-based metal layers, it is known to use dielectric coatings under the silver layers comprising dielectric layers with a stabilizing function intended to promote wetting and nucleation of the silver layer. . Dielectric layers based on crystallized zinc oxide are used in particular for this purpose. In fact, the zinc oxide deposited by the sputtering process crystallizes without requiring additional heat treatment. The zinc oxide-based layer can therefore serve as an epitaxial growth layer for the silver layer.

Another way to prevent the degradation of the silver layers lies in the choice of the layer located above and in contact with the silver layer. Among the known proposals are the use of so-called blocking layers and/or dielectric layers based on crystallized zinc oxide. The objective is to protect the functional layers from possible degradation during deposition of the upper dielectric coating and/or during heat treatment.

The blocking layers are generally based on a metal chosen from nickel, chromium, titanium, niobium, or an alloy of these different metals. The different metals or alloys mentioned can also be partially oxidized, in particular having a sub-stoichiometry in oxygen (for example TiOx or NiCrOx).

These blocking layers are very thin, normally less than 2 nm thick and are likely at these thicknesses to be partially oxidized during heat treatment or during the deposition of an overlying layer. Generally speaking, these blocking layers are sacrificial layers, capable of capturing oxygen coming from the atmosphere or the substrate, thus preventing the oxidation of the silver layer.

Materials comprising, above the functional layer(s) based on silver, a sequence of a blocking layer based on a nickel and chromium alloy and a layer based on zinc oxide are currently used.

However, the use of these thin blocking layers, even associated with stabilizing layers based on zinc oxide, does not make it possible to obtain sufficiently high-performance glazing, notably having sufficiently low emissivity and good mechanical resistance. Indeed, it remains essential according to the invention that the advantageous emissivity properties are obtained without harming the mechanical resistance. Good mechanical resistance translates into good resistance to scratches and brushes, particularly in the EBT test (“Erichsen brush test”).

Good results in terms of resistivity have also been obtained with a material comprising, above the functional layer(s) based on silver, a thick layer based on titanium oxide in contact with the silver. This layer is deposited from a sub-stoichiometric ceramic target by controlling the oxygen in the deposition atmosphere. The Ag/TiOx sequence makes it possible to reduce the emissivity. In addition, the presence of this layer with a high refractive index in contact with the silver contributes:
- to further improve the solar factor in the case where the stack is used as a low emissive stack on face 3 in double glazing, or
- to improve selectivity in the case where the stack is used as a solar control stack on face 2 in double glazing.

However, when using this Ag/TiOx sequence, it is essential to properly control oxidation during sputtering of the titanium oxide layer. If we want to minimize absorption in the titanium oxide-based layer, a significant proportion of oxygen in the deposition atmosphere is required. However, if excess oxygen is introduced during the sputtering of the first few nanometers of the titanium oxide layer, it causes the silver to oxidize. The resistivity of the silver is then degraded.

Finally, in the absence of oxygen or in the presence of a small quantity of oxygen during the spraying of the titanium oxide layer, a gain in resistance per square is observed. However, higher absorption and degraded mechanical properties are also observed. This results in poor EBT test scores. Control of the oxygen used during deposition is a key parameter.

The layer based on titanium oxide is advantageously deposited from a ceramic target, in particular under stoichiometry, in a controlled atmosphere comprising oxygen. Preferably, a first thin layer based on titanium oxide is deposited in contact with the silver layer, from a ceramic target, in a non-oxidizing or very weakly oxidizing atmosphere. Then, a thicker layer based on titanium oxide is deposited from a ceramic target in an oxidizing atmosphere. The layer based on titanium oxide is made up of these two parts. During deposition, the part of the titanium oxide-based layer in contact with the functional layer is less oxidized than the part furthest from the functional layer. By proceeding in this way we obtain both:
- low resistance per square thanks to the Ag / TiOx interface deposited without oxygen and
- low absorption thanks to the second part of the titanium oxide layer.

This deposition in several stages makes it possible to obtain a majority of titanium oxide layer in the stack with a large quantity of oxygen, while protecting the silver-based functional layer with a first layer of titanium oxide. weakly oxidized. The absorption of the stack is then greatly reduced both in the absence of a heat treatment and following a heat treatment.

The Ag/TiOx sequence allows excellent performance and good durability to be obtained, provided that the deposit parameters are controlled. However, adjusting these settings can be quite tricky. It is necessary to determine both the thicknesses and the optimal oxidation conditions for each part of the thick layer of titanium oxide.

There is a need for an industrially usable solution with superior performance achieved in a robust and reproducible manner, without requiring delicate, long and tedious setup time. There is also a need for a solution to obtain these properties of low emissivity and good mechanical resistance at the same time:
- when the stack or the substrate carrying the stack has not undergone heat treatment at high temperature and
- when the stack or the substrate carrying the stack undergoes heat treatment at high temperature.

The applicant has surprisingly discovered that the combined use of a zinc-based layer deposited from a metallic zinc cathode combined with a thick titanium oxide-based layer in the dielectric coating located above of the functional layer makes it possible to obtain advantageous properties without requiring tedious adjustment of the deposition conditions of the layers constituting the stack. Thanks to the presence of the zinc-based layer, the titanium oxide-based layer can be deposited in a single step with high proportions of oxygen while guaranteeing low absorption. Thus, the deposition conditions are simpler and easier to determine industrially than the solution using the Ag/TiOx sequence.

The invention therefore relates to a material comprising a substrate coated with a stack of layers comprising at least one functional metallic layer based on silver and at least two dielectric coatings, each dielectric coating comprising at least one dielectric layer, so as to that each functional metal layer is placed between two dielectric coatings, characterized in that the dielectric coating located above the functional metal layer comprises:
- a zinc-based layer located in contact with the functional layer having a thickness of between 0.3 and 3.0 nm, between 0.3 and 2 nm, between 0.3 and 1 nm or between 0.3 and 0 .8nm and
- a layer based on titanium oxide located above and in contact with the layer based on zinc having a thickness greater than or equal to 3.0 nm.

The invention resulting from this combination makes it possible to obtain:
- low resistivity values,
- low absorption values,
- good mechanical properties of brush resistance without and with heat treatment,
- a simplified deposition process allowing properties to be obtained in a more robust manner.

But above all, the material of the invention has the advantage that these advantageous properties are obtained even when the material coated with the stack or the stack alone has not undergone heat treatment at high temperature. The materials according to the invention can be used interchangeably:

- as deposited, that is to say without having been subjected to any heat treatment at high temperature, in this case neither the substrate coated with the stack, nor the stack alone, has undergone heat treatment at high temperature high,

- treated by laser radiation, in this case, only the stack undergoes heat treatment at high temperature,
- treated by annealing or quenching, in this case the substrate and the stack undergo heat treatment at high temperature.

Obtaining properties regardless of the presence or absence of heat treatment allows greater flexibility in inventory management. This is of significant economic interest.

The applicant has surprisingly discovered that the combined use of the zinc-based layer, the thick layer based on titanium oxide and a layer based on zinc and tin oxide in particular also contributes to obtaining the advantageous properties of the invention. It seems that this layer makes it possible to reduce residual absorption in the event of incomplete oxidation of the titanium oxide-based layer.

The solution of the invention is particularly suitable in the case of stacks with several functional layers based on silver, in particular stacks with two or three functional layers which are particularly fragile from the point of view of scratches.

The present invention is also particularly suitable in the case of stacks with a single functional layer based on silver intended for applications where, for example, high levels of light transmission are sought.

The material according to the invention may have the following characteristics alone or in combination:
- the zinc-based layer is deposited from a metallic zinc target,
- the layer based on titanium oxide is deposited from a ceramic target, in particular under stoichiometry preferably in an oxidizing atmosphere whose percentage in volume flow rate of oxygen represents between 0 and 20%, preferably 2 to 15 %,
- the layer based on titanium oxide has a thickness of between 5 and 30 nm,
- the layer based on titanium oxide comprises an oxidation gradient, the part of the layer based on titanium oxide in contact with the layer based on zinc is more oxidized than the part furthest away,
- the dielectric coating located above the functional layer comprises a layer based on zinc and tin oxide comprising at least 10% by mass of tin relative to the total mass of zinc and tin, located above and in contact with the layer based on titanium oxide,
- the layer based on zinc and tin oxide has a thickness:
- greater than 5 nm,
- less than 40 nm.
- the dielectric coating located above the functional layer comprises a layer comprising silicon chosen from layers of silicon nitride or layers of silicon nitride and zirconium,
- the dielectric coating located below the functional layer comprises a layer based on zinc oxide located in contact with the functional layer,
- the dielectric coating located below the functional layer comprises a layer comprising silicon chosen from layers of silicon nitride or layers of silicon nitride and zirconium,
- the dielectric coating located below the functional layer comprises a layer with a refractive index greater than 2.20,
- the layer with a refractive index greater than 2.20 is chosen from layers based on titanium oxide and layers based on silicon nitride and zirconium,
- the thickness of all layers with a refractive index greater than 2.20 in the dielectric coating located below the functional layer is greater than 10 nm, greater than 15 nm, greater than 20 nm,
- the stack comprises a single functional metallic layer based on silver,
- the stack was subjected to rapid thermal annealing,
- the stack and the substrate have been subjected to heat treatment at a high temperature above 500°C such as quenching, annealing or bending.

The invention also relates to:
- glazing comprising a material according to the invention,
- glazing comprising a material according to the invention mounted on a vehicle or on a building, and
- the process for preparing a material or glazing according to the invention,
- the use of glazing according to the invention as solar control and/or low-emission glazing for buildings or vehicles,
- a building, a vehicle or a device comprising glazing according to the invention.

The method for preparing a material according to the invention, the material comprising a substrate coated with a stack of layers comprising at least one functional metallic layer based on silver and at least two dielectric coatings, each dielectric coating comprising at least a dielectric layer, so that each functional metal layer is placed between two dielectric coatings, is characterized in that the dielectric coating located above the functional metal layer comprises:
- a layer of zinc deposited in metallic form located in contact with the functional layer and
- a layer based on titanium oxide located above and in contact with the metallic zinc layer.

Throughout the description, the substrate according to the invention is considered laid horizontally. The stack of thin layers is deposited on top of the substrate. The meaning of the expressions “above” and “below” and “lower” and “superior” must be considered in relation to this orientation. In the absence of specific stipulation, the expressions “above” and “below” do not necessarily mean that two layers and/or coatings are placed in contact with each other. When it is specified that a layer is deposited “in contact” with another layer or a coating, this means that there cannot be one (or more) layer(s) interposed between these two layers (or layer and coating).

All the light characteristics described are obtained according to the principles and methods of European standards EN 410 relating to the determination of the light and solar characteristics of glazing used in glass for construction. Sunlight entering a building is considered to go from the outside to the inside.

According to the invention, the luminous characteristics are measured according to the illuminant D65 at 2° perpendicular to the material mounted in double glazing:
- TL corresponds to the light transmission in the visible in %,
- Rext corresponds to the exterior light reflection in the visible in %, observer side exterior space,
- Rint corresponds to the interior light reflection in the visible in %, observer side interior space,
- a*T and b*T correspond to the transmission colors a* and b* in the L*a*b* system,
- a*Rext and b*Rext correspond to the reflected colors a* and b* in the L*a*b* system, observer on the exterior space side,
- a*Rint and b*Rint correspond to the colors in reflection a* and b* in the L*a*b* system, observer on the interior space side.

As explained previously, according to the invention the properties must be obtained even when the stack or the substrate carrying the stack has not undergone heat treatment at high temperature.

The present invention therefore relates to the non-heat-treated coated substrate. The stack may not have undergone heat treatment at a temperature above 500°C, preferably 300°C.

The present invention also relates to the heat treated material. The heat treatments are chosen from:
- annealing, for example rapid annealing,
- quenching and/or bending.

The material, that is to say the transparent substrate coated with the stack, may have undergone heat treatment at high temperature. The stack and the substrate may have been subjected to heat treatment at an elevated temperature such as quenching, annealing or bending.

It is also possible to heat treat only the stack. In this case, only the stack may have undergone heat treatment.

In these two cases, the stack may have undergone heat treatment at a temperature above 300°C, preferably 500°C. The heat treatment temperature (at the stack level) is greater than 300°C, preferably greater than 400°C, and better still greater than 500°C.

According to the invention, it is possible to carry out rapid thermal annealing (“Rapid Thermal Process”) such as laser or flash lamp annealing. Rapid thermal annealing is for example described in applications WO2008/096089 and WO2015/185848. In these cases, only the stack is subjected to heat treatment. During this type of treatment, each point of the stack is brought to a temperature of at least 300 ^° C while maintaining a temperature less than or equal to 150 ^° C at any point on the face of the substrate opposite to that on which it is placed. locate the stack. This process has the advantage of only heating the stack, without significant heating of the entire substrate.

In the case of laser processing, the coated materials can be treated using a laser line formed from laser sources such as InGaAs laser diodes or Yb:YAG disk laser. These continuous sources emit at a wavelength between 900 and 1100 nm. The laser line has a length of around 3.3 m, equal to the width 1 of the substrate, and an average width at half-height FWHM between 45 and 100 µm.

The materials are arranged on a roller conveyor so as to move in a direction X, parallel to its length. The laser line is fixed and positioned above the coated surface of the substrate with its longitudinal direction Y extending perpendicular to the direction extending over this entire width.
The position of the focal plane of the laser line is adjusted to lie within the thickness of the functional coating when the substrate is positioned on the conveyor. The surface power of the laser line at the focal plane is less than 100kW/cm2. The substrate was moved under the laser line at a speed of approximately 8 m/min.

The stack may therefore have been subjected to rapid thermal annealing in which each point of the stack is brought to a temperature of at least 300 ^° C while maintaining a temperature less than or equal to 150 ^° C at any point on the face. of the substrate opposite to that on which the stack is located.

It is also possible to combine heat treatments. For example, it is possible to carry out rapid thermal annealing followed by quenching.

The stack and the substrate may have been subjected to heat treatment at a high temperature above 500°C such as quenching, annealing or bending. The substrate coated with the stack can be curved or tempered glass.

The stack is deposited by cathode sputtering assisted by a magnetic field (magnetron process). According to this advantageous embodiment, all the layers of the stack are deposited by cathode sputtering assisted by a magnetic field.

In the absence of specific stipulation, the expressions “above” and “below” do not necessarily mean that two layers and/or coatings are placed in contact with each other. When it is specified that a layer is deposited “in contact” with another layer or a coating, this means that there cannot be one (or more) layer(s) interposed between these two layers (or layer and coating).

Unless otherwise stated, the thicknesses mentioned in this document are physical thicknesses and the layers are thin layers. By thin layer is meant a layer having a thickness of between 0.1 nm and 100 micrometers.

In the present description, unless otherwise indicated, the expression "based on", used to qualify a material or a layer as to what it contains, means that the mass fraction of the constituent which it comprises is at least 50%, in particular at least 70%, preferably at least 90%.

The stack of thin layers comprises at least one functional layer and at least two dielectric coatings comprising at least one dielectric layer, so that each functional layer is arranged between two dielectric coatings.

The stack of thin layers may comprise at least two silver-based metallic functional layers and at least three dielectric coatings comprising at least one dielectric layer, so that each functional layer is arranged between two dielectric coatings.

The stack of thin layers may comprise at least three functional layers and at least four dielectric coatings comprising at least one dielectric layer, so that each functional layer is arranged between two dielectric coatings.

The silver-based metallic functional layers comprise at least 95.0%, preferably at least 96.5% and better still at least 98.0% by mass of silver relative to the mass of the functional layer. Preferably, a silver-based functional metal layer comprises less than 1.0% by mass of metals other than silver relative to the mass of the silver-based functional metal layer.

The silver-based metallic functional layers have a thickness:
- greater than 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 10 nm, 11 nm, 12 nm, 13 nm, 14 nm, 15 nm or 16 nm, and/or
- less than 25nm, 22nm, 20nm, 18.nm.

Dielectric coatings include dielectric layers. By “dielectric layer” within the meaning of the present invention, it must be understood that from the point of view of its nature, the material is “non-metallic”, that is to say it is not a metal. In the context of the invention, this term designates a material having an n/k ratio over the entire visible wavelength range (from 380 nm to 780 nm) equal to or greater than 5. n designates the index of real refraction of the material at a given wavelength and k represents the imaginary part of the refractive index at a given wavelength; the ratio n/k being calculated at a given wavelength which is identical for n and for k.

The thickness of a dielectric coating corresponds to the sum of the thicknesses of the layers constituting it. Preferably, the dielectric coatings have a thickness greater than 10 nm, greater than 15 nm, between 15 and 200 nm, between 15 and 100 nm or between 15 and 70 nm.

The dielectric layers of the coatings have the following characteristics alone or in combination:
- they are deposited by magnetic field-assisted cathode sputtering,
- they generally have a thickness greater than 2 nm, preferably between 4 and 200 nm.

The dielectric layers, in addition to their optical function, can have various other functions. As an example, we can cite stabilizing layers, smoothing layers, and barrier layers.

The dielectric layers are conventionally chosen from layers based on oxide, based on nitride or based on oxynitride. The oxide layers of one or more elements comprise mainly oxygen and very little nitrogen. The oxide-based layers include in particular at least 90% in atomic percentage of oxygen relative to the oxygen and nitrogen in said layer. Nitride-based layers consist mainly of nitrogen and very little oxygen. The nitride-based layers comprise at least 90 atomic percent nitrogen relative to the oxygen and nitrogen in said layer. Oxynitride-based layers include a mixture of oxygen and nitrogen. The layers based on silicon oxynitride comprise 10 to 90% (limits excluded) in atomic percentage of nitrogen relative to the oxygen and nitrogen in said layer.

The quantities of oxygen and nitrogen in a layer are determined as atomic percentages relative to the total quantities of oxygen and nitrogen in the layer considered.

The dielectric layers are conventionally chosen from:
- the layers comprising silicon, aluminum and/or zirconium, optionally doped with at least one other element,
- layers based on zinc and tin oxide,
- layers based on titanium oxide,
- layers based on zinc oxide.

According to the invention, a zinc-based layer is located in contact with the functional layer. In the following paragraphs, the zinc-based layers are defined as they are obtained during deposition. To the extent that these layers are thin, it is not possible to determine with certainty, depending on the thicknesses deposited, how this zinc-based layer is modified following the deposition of the titanium oxide layer.

The zinc-based layer is deposited by sputtering from a metallic zinc target. The deposition atmosphere is without oxygen or includes very little oxygen, preferably without oxygen, i.e. non-oxidizing. This zinc-based layer is partly oxidized to zinc oxide during the deposition of the titanium oxide-based layer. Following the deposition of the titanium oxide layer, there is preferably no absorption due to the non-oxidation of the metallic zinc. However, when the zinc-based layer is deposited in metallic form, the zinc seems to alloy or associate with silver in the form of an AgZn phase. It is possible to carry out analyzes proving the presence of this AgZn phase. When this phase is detected, there is a strong presumption that the zinc in contact with the silver has indeed been deposited from a metallic target in the absence of oxygen or under low oxidizing conditions.

The thickness of this layer can be as thin as that of a standard blocking layer (<1nm), as long as the functional silver-based layer is not degraded by the oxygen present during the deposition of the silver. next layer based on titanium oxide, deposited with more oxygen. It has a thickness between 0.3 and 3.0 nm, between 0.3 and 2 nm, between 0.3 and 1 nm or between 0.3 and 0.8 nm.

The zinc-based layers are deposited in metallic form. The zinc-based layers comprise at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% by mass of zinc relative to the total mass of elements other than oxygen and nitrogen in the layer to be zinc base. Zinc-based layers can be chosen from:
- the zinc layers,
- the doped zinc layers,
- layers based on zinc alloy.

According to the invention, the term “zinc layer” means metallic layers of pure zinc which may still include some impurities. In this case, the total mass of zinc represents at least 99% by mass relative to the total mass of the elements other than oxygen and nitrogen in the zinc-based layer.

According to the invention, the doped zinc layers comprise at least 90.0%, at least 95%, at least 96%, at least 97% or at least 98% by mass of zinc relative to the total mass of the other elements. as oxygen and nitrogen in the zinc-based layer.

The doped zinc layers can be chosen from layers based on zinc and at least one element chosen from titanium, nickel, aluminum, tin, niobium, chromium, magnesium, copper, silicon, silver or gold.

According to the invention, the layers based on zinc alloy comprise at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%. or at least 90% by mass of zinc relative to the total mass of elements other than oxygen and nitrogen in the zinc-based layer.

The layers based on zinc alloy can be chosen from layers based on zinc and at least one element chosen from titanium, nickel, chromium, tin. By way of example, we can cite binary alloys of zinc and titanium such as Zn ₂ Ti or ternary alloys based on zinc, nickel and chromium such as ZnNiCr.

The thickness of the zinc-based layer can be:
- greater than or equal to 0.3 nm, greater than or equal to 0.5 nm and/or
- less than or equal to 3.0 nm, less than or equal to 2.0 nm, less than or equal to 1.5 nm, less than or equal to 1.0 nm, less than or equal to 0.8 nm.

The stack comprises at least one layer based on titanium oxide located above and in contact with the layer based on zinc having a thickness greater than equal to 3 nm. The layer is a layer based on titanium oxide over this entire thickness. According to the invention, this layer based on titanium oxide is part of a dielectric coating located above the silver layer. This means that when determining the thickness of this dielectric coating, we take into consideration the thickness of this layer.

This layer based on thick titanium oxide close to the silver contributes to obtaining the advantageous properties of the invention. This oxide layer is non-absorbent, especially when it is mainly deposited from a ceramic target in an oxidizing atmosphere.

The layers based on titanium oxide comprise at least 50%, at least 60%, at least 70%, at least 80%, at least 95.0%, at least 96.5% and better still at least 98.0 % by mass of titanium relative to the mass of all the elements constituting the layer based on titanium oxide other than oxygen.

The layers based on titanium oxide can have a thickness:
- greater than or equal to 3 nm, greater than or equal to 4 nm, greater than or equal to 5 nm, and/or
- less than or equal to 30 nm, less than or equal to 25 nm, less than or equal to 20 nm, less than or equal to 15 nm, less than or equal to 10 nm, less than or equal to 8 nm, less than or equal to 6 nm.
The layers based on titanium oxide can have a thickness of between 5 and 30 nm.

The titanium oxide-based layers may include or consist of elements other than titanium and oxygen. These elements can be chosen from silicon, chromium and zirconium. Preferably, the elements are chosen from zirconium. Preferably, the layer based on titanium oxide comprises at most 35%, at most 20% or at most 10% by mass of elements other than titanium relative to the mass of all the elements constituting the layer based on titanium oxide. titanium oxide other than oxygen.

Layers based on titanium oxide can be obtained:
- by cathode sputtering,
- from a metallic titanium target or a ceramic target based on titanium oxide, preferably under stoichiometry.
When the titanium oxide-based layer is obtained from a metallic target, the deposition atmosphere includes significant proportions of oxygen.
The layers based on titanium oxide are preferably obtained from a ceramic target of titanium oxide, preferably under oxygen stoichiometry, in an atmosphere comprising oxygen. The quantity of oxygen in the deposition atmosphere can be adapted according to the desired properties.
The layer based on titanium oxide is preferably deposited from a ceramic target, in particular sub-stoichiometrically in an oxidizing atmosphere, preferably whose percentage in oxygen volume flow represents between 0 and 20%, preferably 2 at 15%.

According to the preferred embodiment, a layer based on titanium oxide is deposited from a ceramic target, in particular under stoichiometry. The titanium oxide-based layer can be deposited from a sub-stoichiometric TiO _x ceramic target, where x is a number different from the stoichiometry of the titanium oxide TiO ₂ , i.e. different from 2 and preferably less than 2, in particular between 0.75 times and 0.99 times the normal stoichiometry of the oxide. TiOx can in particular be such that 1.5 < x < 1.98 or 1.5 < x < 1.7, or even 1.7 < x < 1.95.

According to the invention, it is deposited in an atmosphere comprising an optimized quantity of oxygen to obtain the desired properties. The deposition atmosphere includes a mixture of noble gas (He, Ne, Xe, Ar, Kr) and oxygen. The noble gas is preferably argon. The following parameters allow you to define the conditions for deposition by sputtering:
- the deposition pressure,
- the composition of the gases in volume flow (scm unit “standard cubic centimeter per minute”). According to the invention, the following parameters were used:
- the pressure in the deposition enclosure is between 1 and 15 µbar, preferably 2 and 10 µbar or 2 and 8 µbar,
- the deposition atmosphere includes a mixture of argon and oxygen.

The maximum oxygen threshold may vary to some extent depending on, for example:
- the nature of the TiOx target, in particular its oxygen substoichiometry or
- power,
- the configuration of the cathode sputtering deposition chamber (geometry, locations of gas inlets, etc.)
Indeed, if a low deposition power is used, the quantities of oxygen volume flow that can be used during deposition will be lower because the TiOx is deposited more slowly and is therefore more likely to oxidize.

Those skilled in the art are able to define a satisfactory controlled atmosphere by varying these parameters to a certain extent. Those skilled in the art are particularly able to determine the power to be applied to the target and the volume flow rates of oxygen and noble gases.

According to one embodiment, the layer based on titanium oxide is deposited from a ceramic target, in particular under stoichiometry, in an atmosphere comprising oxygen.

According to one embodiment, a first thin layer based on titanium oxide is deposited in contact with the zinc-based layer, from a ceramic target, in a slightly oxidizing atmosphere. Then, a thicker layer based on titanium oxide is deposited from a ceramic target in a more oxidizing atmosphere. The layer based on thick titanium oxide according to the invention consists of these two thicknesses. The part of the titanium oxide-based layer in contact with the zinc-based layer is less oxidized than the part furthest away. The layer based on titanium oxide includes an oxidation gradient, the part of the layer based on titanium oxide in contact with the layer based on zinc is more oxidized than the part furthest away.

The titanium oxide-based layer is located below and in contact with a dielectric layer. The dielectric layer may be based on oxide, nitride or oxynitride of one or more elements chosen from silicon, zirconium, titanium, aluminum, tin and/or zinc. Preferably, this dielectric layer has a thickness greater than 5 nm, 8 nm, 10 nm or 15 nm.

The stack may comprise at least one layer comprising silicon or aluminum. Preferably, the dielectric coating located above the functional layer may comprise a layer comprising silicon chosen in particular from layers of silicon nitride or layers of silicon nitride and zirconium. Each dielectric coating may also comprise at least one layer comprising silicon.

The layers comprising silicon are extremely stable to thermal treatments. For example, we do not observe any migration of the elements constituting them. Consequently, these elements are not likely to alter the silver layer. Layers comprising silicon therefore also contribute to the non-alteration of the silver layers and therefore to obtaining a low emissivity after heat treatment.

The layers comprising silicon comprise at least 50% by mass of silicon relative to the mass of all the elements constituting the layer comprising silicon other than nitrogen and oxygen.

The layers comprising silicon can be chosen from layers based on oxide, based on nitride or based on oxynitride such as layers based on silicon oxide, layers based on silicon nitride and layers based on silicon oxynitride.

The silicon oxide-based layers comprise at least 90 atomic percent oxygen relative to the oxygen and nitrogen in the silicon oxide-based layer. The silicon nitride-based layers comprise at least 90 atomic percent nitrogen relative to the oxygen and nitrogen in the silicon nitride-based layer. The layers based on silicon oxynitride include 10 to 90% (excluding limits) in atomic percentage of nitrogen relative to the oxygen and nitrogen in the layer based on silicon oxide. Preferably, the layers based on silicon oxide are characterized by a refractive index at 550 nm, less than or equal to 1.55. Preferably, the layers based on silicon nitride are characterized by a refractive index at 550 nm, greater than or equal to 1.95.

The layers comprising silicon may comprise or consist of elements other than silicon, oxygen and nitrogen. These elements can be chosen from aluminum, boron, titanium, and zirconium. The layers comprising silicon may comprise at least 2%, at least 5% or at least 8% by mass of aluminum relative to the mass of all the elements constituting the layer comprising silicon other than oxygen and nitrogen.

The layers comprising aluminum can be chosen from layers based on oxide, based on nitride or based on oxynitride such as layers based on aluminum oxide such as Al2O3, layers based on aluminum nitride such as AIN and layers based on aluminum oxynitride such as AlOxNy.

The layers based on silicon nitride and zirconium Si _x Zr _y N _z are part of the layers comprising silicon, in particular layers based on silicon nitride. The refractive index of the layers based on silicon nitride and zirconium increases with the increase in the proportions of zirconium in said layer.

The silicon nitride-based layers may include aluminum and/or zirconium. Such layers may include, in atomic proportion relative to the atomic proportion of Si, Zr and Al:

- 50 to 98%, 60 to 90%, 60 to 70 atomic% of silicon,

- 0 to 10%, 2 to 10 atomic % of aluminum

- 0 to 30%, 10 to 40% or 15 to 30 atomic% of zirconium.

Preferably, the dielectric coating located above the silver layer comprises a layer comprising silicon. These layers comprising silicon have, in order of increasing preference, a thickness:
- less than or equal to 40 nm and/or
- greater than or equal to 5 nm, greater than or equal to 10 nm or greater than or equal to 15 nm.

Preferably, at least one dielectric coating comprises a layer comprising silicon chosen from layers based on silicon nitride. Preferably, the dielectric coating located above the functional layer based on silver comprises a layer comprising silicon chosen from layers based on silicon nitride. Each dielectric coating may comprise a layer comprising silicon chosen from layers based on silicon nitride.

Preferably, the sum of the thicknesses of all layers comprising silicon in the dielectric coating located above the first functional silver-based metal layer may be greater than 35%, greater than 50%, of the total thickness. of the dielectric coating.

Preferably, the sum of the thicknesses of all layers comprising silicon based on silicon nitride in each dielectric coating located above the first functional metal layer based on silver can be greater than 35%, greater than 50% , of the total thickness of the dielectric coating.

The dielectric coating located above the functional layer may comprise a layer based on zinc and tin oxide comprising at least 10% by mass of tin relative to the total mass of zinc and tin, located above and in contact with the layer based on titanium oxide.

The layer based on zinc and tin oxide comprises in mass of tin relative to the total mass of zinc and tin:
- at least 10%, at least 15%, at least 20%, at least 30%, at least 40%, at least 45%, at least 50% or at least 55%,
- not more than 90%, not more than 80%, not more than 70%, not more than 65% or not more than 60% by mass of zinc. The layer based on zinc and tin oxide located in the dielectric coating above the functional layer based on silver has a thickness:
- greater than 5 nm, greater than 10 nm, greater than 15 nm, greater than 18 nm,
- less than 40 nm, less than 30 nm, less than 25 nm.

The dielectric coating located above the silver layer may include:
- a zinc-based layer,
- a layer based on titanium oxide,
- a layer comprising silicon, preferably a layer based on silicon nitride or a layer based on silicon nitride and zirconium or a combination of these two layers.

The dielectric coating located above the silver layer may include:
- a zinc-based layer,
- a layer based on titanium oxide,
- a layer based on zinc and tin oxide comprising at least 10% by mass of tin relative to the total mass of zinc and tin, located above and in contact with the layer based on tin titanium oxide,
- a layer comprising silicon, located above and in contact with the layer based on zinc and tin oxide, preferably a layer based on silicon nitride or a layer based on silicon nitride and zirconium or a combination of these two layers.

The dielectric coating located below the functional layer may include a so-called stabilizing layer which reinforces the adhesion of the functional layer to the layers surrounding it. The stabilizing layers are preferably layers based on zinc oxide optionally doped, for example, with aluminum. The zinc oxide is crystallized. The layer based on zinc oxide comprises, in increasing order of preference, at least 90.0%, at least 92%, at least 95%, at least 98.0% by mass of zinc relative to the mass of elements other than oxygen in the zinc oxide-based layer.

According to this embodiment, the dielectric coating located below the functional layer may comprise a layer based on zinc oxide located directly in contact with the functional layer. Indeed, it is advantageous to have a stabilizing layer, below and in contact with a functional layer, because it facilitates the adhesion and crystallization of the silver-based functional layer and increases its quality and stability. . The metallic functional layer is deposited above and in contact with a layer based on zinc oxide. The zinc oxide-based layer can be deposited from a ceramic target, with or without oxygen or from a metallic target. The zinc oxide layers have a thickness:
- at least 1.0 nm, at least 2.0 nm, at least 3.0 nm, at least 4.0 nm, at least 5.0 nm, at least 6.0nm and/or
- not more than 25 nm, not more than 10 nm, not more than 8.0 nm.

The dielectric coating located below the silver layer may also comprise a layer based on zinc and tin oxide comprising at least 10% by mass of tin relative to the total mass of zinc and tin. , located below and in contact with the zinc oxide-based layer.

The stack can therefore comprise one or more layers based on zinc and tin oxide comprising at least 10% by mass of tin relative to the total mass of zinc and tin, located above and at the bottom. contact of the layer based on titanium oxide. The layers based on zinc and tin oxide preferably comprise by mass of tin relative to the total mass of zinc and tin:
- at least 10%, at least 15%, at least 20%, at least 30%, at least 40%, at least 45%, at least 50% or at least 55%,
- not more than 90%, not more than 80%, not more than 70%, not more than 65% or not more than 60% by mass of zinc.
The layers based on zinc and tin oxide have a thickness:
- greater than 5 nm, and/or
- less than 40 nm, less than 30 nm, less than 25 nm.

The dielectric coating located below the functional layer may comprise a layer comprising silicon chosen from silicon nitride layers or silicon nitride and zirconium layers.

The dielectric coating located below the functional layer may include a layer with a refractive index greater than 2.20. The presence of high index layers above and below the silver-based functional layer contributes to obtaining high light transmission.

Among the dielectric layers, we distinguish, depending on their refractive index at 550 nm, layers with a low refractive index, layers with an intermediate refractive index and layers with a high refractive index. Low to low refractive index layers have a refractive index less than 1.70. Intermediate refractive index layers have a refractive index between 1.70 and 2.2. High refractive index layers have a refractive index greater than 2.2.

High refractive index layers can be chosen from:
- layers based on titanium oxide (n550=2.4),
- layers based on mixed titanium oxide and another component chosen from the group consisting of Zn, Zr and Sn,
- the layers based on a layer of zirconium nitride (n 550 = 2.55),
- layers based on silicon nitride and zirconium (n550 nm = 2.20 - 2.40),
- the layers based on a layer of zirconium oxide,
- layers based on manganese oxide MnO (n550 = 2.16),
- the layers based on a layer of tungsten oxide (n550 = 2.15),
- the layers based on a layer of niobium oxide (n550 = 2.30),
- layers based on a layer of bismuth oxide (n 550 = 2.60).
Preferably, the high refractive index layer is chosen from the layers based on titanium oxide and the layer based on silicon nitride and zirconium.

Preferably, the stack does not include a metallic or titanium oxide-based blocking layer below and in contact with the functional silver-based metallic layer. In this case, the functional silver-based metal layer is located above and in contact with a dielectric layer of the dielectric coating. Preferably, this dielectric layer is a stabilizing layer.

The dielectric coating located below the functional layer may comprise a sequence of layers, defined starting from the substrate, chosen from:
- layer based on titanium oxide (high index layer) // layer based on zinc oxide,
- layer based on silicon nitride // layer based on zinc oxide,
- layer based on silicon nitride and zirconium (high index layer) // layer based on zinc oxide,
- layer based on silicon nitride // layer based on silicon nitride and zirconium (high index layer) // layer based on zinc oxide,
- layer based on silicon nitride // layer based on titanium oxide (high index layer) // layer based on zinc oxide,
- layer based on silicon nitride and zirconium (high index layer) // layer based on titanium oxide (high index layer) // layer based on zinc oxide,
- layer based on silicon nitride // layer based on silicon nitride and zirconium // layer based on titanium oxide (high index layer) // layer based on zinc oxide,
- layer based on titanium oxide (high index layer) // layer based on zinc and tin oxide // layer based on zinc oxide,
- layer based on silicon nitride // layer based on zinc and tin oxide // layer based on zinc oxide,
- layer based on silicon nitride and zirconium (high index layer) // layer based on zinc and tin oxide // layer based on zinc oxide,
- layer based on silicon nitride // layer based on silicon nitride and zirconium (high index layer) // layer based on zinc and tin oxide // layer based on zinc oxide,
- layer based on silicon nitride // layer based on titanium oxide (high index layer) // layer based on zinc and tin oxide // layer based on zinc oxide?
- layer based on silicon nitride and zirconium // layer based on titanium oxide (high index layer) // layer based on zinc and tin oxide // layer based on zinc oxide ,
- layer based on silicon nitride // layer based on silicon nitride and zirconium // layer based on titanium oxide (high index layer) // layer based on zinc and tin oxide / / layer based on zinc oxide.

When the stack includes a layer of silicon nitride and a layer of silicon nitride and zirconium, these layers are different, that is to say they are not composed of the same elements in the same proportions.

The dielectric coating located above the functional layer may comprise a sequence of layers, defined starting from the substrate, chosen from:
- the zinc-based layer // the titanium oxide-based layer // silicon nitride-based layer,
- the layer based on zinc // the layer based on titanium oxide // layer based on silicon nitride and zirconium,
- the layer based on zinc // the layer based on titanium oxide // layer based on silicon nitride and zirconium // layer based on silicon nitride,
- the zinc-based layer // the titanium oxide-based layer // zinc and tin oxide-based layer // silicon nitride-based layer,
- the zinc-based layer // the titanium oxide-based layer // zinc and tin oxide-based layer // silicon oxide-based layer,
- the layer based on zinc // the layer based on titanium oxide // layer based on zinc and tin oxide // layer based on silicon nitride and zirconium,
- the layer based on zinc // the layer based on titanium oxide // layer based on zinc and tin oxide // layer based on silicon nitride and zirconium // layer based on silicon nitride,
- the zinc-based layer // the titanium oxide-based layer // zinc and tin oxide-based layer // silicon nitride-based layer // tin oxide-based layer zinc and tin,
- the zinc-based layer // the titanium oxide-based layer // silicon nitride-based layer // silicon oxide-based layer,
- the zinc-based layer // the titanium oxide-based layer // zinc and tin oxide-based layer // silicon nitride-based layer // tin oxide-based layer silicon,
- the layer based on zinc // the layer based on titanium oxide // layer based on silicon nitride and zirconium // layer based on silicon nitride // layer based on silicon oxide.

The stack of thin layers may optionally include a protective layer. The protective layer is preferably the last layer of the stack, that is to say the layer furthest from the coated substrate of the stack (before heat treatment). These layers generally have a thickness of between 0.5 and 10 nm, between 1 and 5 nm, between 1 and 3 nm or between 1 and 2.5 nm. This protective layer can be chosen from a layer of titanium, zirconium, hafnium, silicon, zinc and/or tin, this or these metals being in metallic, oxidized or nitrided form.

According to one embodiment, the protective layer is based on zirconium oxide and/or titanium oxide, preferably based on zirconium oxide, titanium oxide or titanium and zirconium oxide. When we determine the thickness of a dielectric coating, we take into account the thickness of the protective layer.

The transparent substrates according to the invention are preferably made of a rigid mineral material, such as glass, or organic based on polymers (or polymer).

The organic transparent substrates according to the invention can also be made of polymer, rigid or flexible. Examples of polymers suitable according to the invention include, in particular:
- polyethylene,
- polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN);
- polyacrylates such as polymethyl methacrylate (PMMA);
- polycarbonates;
- polyurethanes;
- polyamides;
- polyimides;
- fluoropolymers such as fluoroesters such as ethylene tetrafluoroethylene (ETFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), ethylene of chlorotrifluoroethylene (ECTFE), ethylene-propylene fluorinated copolymers (FEP);
- photocrosslinkable and/or photopolymerizable resins, such as thiolene, polyurethane, urethane-acrylate, polyester-acrylate and
- polythiourethanes.

The substrate is preferably a sheet of glass or glass ceramic. The substrate is preferably transparent, colorless (it is then a clear or extra-clear glass) or colored, for example blue, gray or bronze. The glass is preferably of the soda-lime-silico type, but it can also be of borosilicate or alumino-borosilicate type glass. According to a preferred embodiment, the substrate is made of glass, in particular silico-soda-lime or of polymeric organic material.

The substrate advantageously has at least one dimension greater than or equal to 1 m, or even 2 m and even 3 m. The thickness of the substrate generally varies between 0.5 mm and 19 mm, preferably between 0.7 and 9 mm, in particular between 2 and 8 mm, or even between 4 and 6 mm. The substrate can be flat or curved, or even flexible.

As explained previously, the solution of the invention is suitable:
- for low emissive applications when an increase in light transmission and solar factor is sought and
- for solar control applications when an increase in selectivity is sought.

The invention also relates to glazing comprising at least one material according to the invention. The invention relates to glazing which can be in the form of monolithic, laminated and/or multiple glazing, in particular double glazing or triple glazing.

Double glazing has 4 faces, face 1 is outside the building and therefore constitutes the exterior wall of the glazing, face 4 is inside the building and therefore constitutes the interior wall of the glazing, faces 2 and 3 being inside the double glazing. The stack according to the invention is located on face 2 or on face 3.

Triple glazing has 6 faces, face 1 is outside the building and therefore constitutes the exterior wall of the glazing, face 6 is inside the building and therefore constitutes the interior wall of the glazing, faces 2 and 3 and 4 and 5 being inside the double glazing. The stack according to the invention can be found on face 2, on face 3 and/or on face 5.

Laminated glazing comprises at least one first substrate/sheet(s)/second substrate type structure. The polymeric sheet may in particular be based on polyvinyl butyral PVB, ethylene vinyl acetate EVA, polyethylene terephthalate PET, polyvinyl chloride PVC. The stack of thin layers is positioned on at least one of the faces of one of the substrates.

The invention therefore concerns:
- multiple glazing of double glazing type with stacking on face 2,
- multiple glazing of double glazing type with stacking on face 3,
- multiple glazing of triple glazing type with stacking on face 2 and face 5,
- laminated glazing with stacking on face 2 or 3.
These glazings can be mounted on a building or a vehicle.

The following examples illustrate the invention.

Examples

I. Preparation of substrates: Stacks, deposition conditions
Stacks of thin layers defined below are deposited on clear soda-lime glass substrates with a thickness of 4 mm. In the examples of the invention:
- the functional layers are silver layers (Ag),
- the dielectric layers are based on silicon nitride doped with aluminum (Si₃NOT₄: Al), based on silicon zirconium nitride doped with aluminum (SiZrN: Al), based on zinc tin oxide (SnZnO), based on zinc oxide doped with aluminum (ZnO: Al).
TiOx titanium oxide layers are deposited from a ceramic TiOx target with or without oxygen in the deposition atmosphere.
The zinc-based layers are deposited using a metallic zinc target doped with aluminum.
The conditions for deposition of the layers, which were deposited by sputtering (so-called “cathode magnetron sputtering”), are summarized in Table 1.

Materials Composition target Pressure Power Gas sccm Ar _O2 No. ₂ Ar/O ₂ (90/10) ZnO ZnO:Al 2%wt ceramic 2 µbar 1300W 40 2 - - Zn Zn:Al 2%wt metallic 2 µbar 750W 10 28 - - TiOx_0% TiOx ceramic 2 µbar 2000W 30 0 - - TiOx_5% TiOx ceramic 2 µbar 2000W 20 0 - 20 SnZnO Sn:Zn 60/40%wt metallic 2 µbar 1000W 7 44 Ag Ag metallic 8 µbar 210W 80 - - - Si3N4 Si:Al 8%wt metallic 2 µbar 2000W 18 - 24 - SiZrN Si:Zr 27% at metallic 2 µbar 1000W 15 - 15 -

%wt: % by weight; at%: atomic.

Different stacks on glass substrate were tested.
The materials according to the invention are intended to be used:
- as deposited, i.e. without having been subjected to any heat treatment at high temperature, hereinafter BT. Neither the coated substrate of the stack, nor the stack alone, has undergone heat treatment at high temperature,
- treated by laser radiation, hereinafter laser, in this case, only the stack undergoes heat treatment at high temperature,
- treated in the Naber® oven at 650°C for 10 min, hereinafter “Naber®”,
- treated by quenching, hereinafter “Tempered”.

Laser radiation processing involves processing coated substrates using a laser line formed from a disk laser. The following conditions were used:
- disk laser source: Yb:YAG,
- wavelength: 1030nm,
- width: 60µm,
- power density: 70kW/cm².

The square resistance Rsq, corresponding to the resistance referred to the surface, is measured by induction with a Nagy SMR-12.
Brush resistance tests were carried out before and after heat treatment (“Erichsen brush test” before EBT heat treatment, after L-EBT laser heat treatment, after TT-EBT quenching type heat treatment). Each sample is observed after 300 cycles. The Ok boxes indicate good performance in the EBT or L-EBT test after 300 cycles, i.e. the absence of scratches or delamination. The Nok boxes indicate poor performance in the EBT or L-EBT test after 300 cycles, i.e. the presence of scratches and/or delamination.

I I. First series of tests
The table below lists the materials and physical thicknesses in nanometers (unless otherwise indicated) of each layer or coating which constitutes the stacks according to their positions with respect to the substrate carrying the stack.

Materials Layers Ref.1a Ref.1b Ref.1c Ref.1d I.1a Rev. dielectric TiOx 1.5 1.5 1.5 1.5 1.5 If ₃ N ₄ 40 40 40 40 40 TiOx 5% - 0 5 4 5 TiOx 0% - 5 0 1 - ZnO 5 - - - - Zn - - - - 0.5 NiCr 0.7 - - - - Functional layer Ag 11 11 11 11 11 Rev. dielectric ZnO 5 5 5 5 5 SiZrN 15 15 15 15 15 Si3N4 15 15 15 15 15 Substrate (mm) glass 4 4 4 4 4

The table below shows all the results, Rsq, Abs, and EBT and L-EBT tests.

Ref.1a Ref.1b Ref.1c Ref.1d I.1a Rsq Abs Rsq Abs Rsq Abs Rsq Abs Rsq Abs BT 4.6 9.1 4 , 1 9.0 6.9 9.1 4 , 4 7 , 7 4 , 4 7 , 1 Laser 3.6 6.0 3 , 0 6.4 3.6 4 , 7 3 , 0 5 , 3 3 , 3 4 , 7 Naber® 3.5 5.6 3.3 7.1 3.4 4 , 7 3 , 1 4 , 3 3 , 4 4 , 8 Soaked 3.5 5.7 3.2 7.9 4.3 12.5 2 , 9 5 , 6 3 , 3 5 , 1 EBT and L-EBT OK nok OK nok OK

1. Material x such s that filed s
For the material as deposited (BT), the resistance per square and the absorption are both degraded in the case of using a layer of titanium oxide deposited in an oxidizing atmosphere in contact with silver (comparison Ref.1c and Ref.1a). This is due to excessive amounts of oxygen during deposition of the titanium oxide layer and the resulting degradation of silver.
The introduction of the metallic zinc layer prevents the degradation of the silver layer even at such thin thicknesses (0.5 nm) and leads to the lowest absorption values (7.1% for the example of the invention I.1a compared to the references).
But above all, the EBT of the stack according to the invention is satisfactory whereas this is not the case for references Ref.1b and Ref.1d comprising in contact with silver a layer of TiOx deposited without oxygen.

2. Material x laser treated
For laser-treated stacks, a similar trend is observed. The stacking of the invention leads to the lowest absorptions. The resistance per square is satisfactory.

3. Material x treaty s at Naber ®
For the case of stacks treated with Naber®, the stacks of the invention have both low absorption and low resistance per square and satisfactory mechanical properties.

II. Second series of tests
In these examples, we test the influence of the presence of a layer of zinc and tin oxide in the dielectric coating located above the silver layer.

Materials Layers Ref.2a Ref.2b Ref.2c Ref.2d I.2a Rev. dielectric TiOx 1.5 1.5 1.5 1.5 1.5 If ₃ N ₄ 35 35 35 35 35 SnZnO 5 5 5 5 5 TiOx 5% - 0 5 4 5 TiOx 0% - 5 0 1 - ZnO 5 - - - - Zn - - - - 0.5 NiCr 0.7 - - - - Functional layer Ag 11 11 11 11 11 Rev. dielectric ZnO 5 5 5 5 5 SiZrN 15 15 15 15 15 Si3N4 15 15 15 15 15 Substrate (mm) glass 4 4 4 4 4

Ref.2a Ref.2b Ref.2c Ref.2d I.2a Rsq Abs Rsq Abs Rsq Abs Rsq Abs Rsq Abs BT 4.7 8.9 4.3 7.8 7.9 9.0 4.8 7.3 4.3 6.4 Laser 3.4 5.0 3.3 5.1 3.7 4.6 3.5 4.6 3.0 4.2 Naber® 3.3 5.3 3.9 5.6 3.4 4.5 3.5 4.8 3.1 4.5 Soaked 4.7 5.7 8.2 10.2 7.9 8.8 6.7 9.1 4.9 6.9 EBT and L-EBT OK nok OK OK OK TT EBT nok OK OK OK OK

1. Material x as deposited s
For the material as deposited (BT), the resistance per square and the absorption are both degraded in the case of using a layer of titanium oxide deposited in an oxidizing atmosphere in contact with silver (comparison Ref.2c and Ref.2a). This is due to excessive amounts of oxygen during deposition of the titanium oxide layer and the resulting silver degradation.
The introduction of the metallic zinc layer prevents the degradation of the silver layer even at such thin thicknesses (0.5 nm) and leads to the lowest absorption values (6.4% for the example of invention I.2a compared to the references) and the lowest resistance values per square (4.3Ω/□).
But above all, the EBT of the stack according to the invention is satisfactory whereas this is not the case for references Ref.2b comprising in contact with silver a layer of TiOx deposited without oxygen.

2. Laser processed materials
For laser-treated stacks, a similar trend is observed. The stacking of the invention leads to the lowest absorption and resistance values per square (4.2% and 3.0Ω/□). The introduction of the zinc and tin oxide layer leads to a notable improvement in square resistance and absorption (I.1a compared to I.2a).
The L-EBT test of the stack according to the invention is satisfactory whereas this is not the case for references Ref.2b comprising, in contact with silver, a layer of TiOx deposited without oxygen.

3. Material x treated with Naber ® or quenching
For the case of stacks treated with Naber®, the stack of the invention leads to the lowest absorption and resistance values per square (4.5% and 3.1 Ω/□).
For the case of quenched stacks, the presence of the layer based on zinc and tin oxide in contact with the titanium oxide layer causes an oxidation-reduction reaction between the TiOx and the SnZnO leading to a degradation of resistance per square and absorption. All stacks comprising the TiOx/SnZnO sequence have degraded performance after quenching. However, surprisingly, the stack of the invention presents a lower level of degradation.

Claims (17)

Material comprising a substrate coated with a stack of layers comprising at least one functional metallic layer based on silver and at least two dielectric coatings, each dielectric coating comprising at least one dielectric layer, so that each functional metallic layer is placed between two dielectric coatings, characterized in that the dielectric coating located above the functional metal layer comprises:
- a zinc-based layer located in contact with the functional layer having a thickness of between 0.3 and 3.0 nm, and
- a layer based on titanium oxide located above and in contact with the layer based on zinc having a thickness greater than or equal to 3.0 nm. Material according to the preceding claim, characterized in that the zinc-based layer is deposited from a metallic zinc target. Material according to any one of the preceding claims, characterized in that the layer based on titanium oxide is deposited from a ceramic target, in particular under stoichiometry. Material according to any one of the preceding claims, characterized in that the layer based on titanium oxide has a thickness of between 5 and 30 nm. Material according to any one of the preceding claims, characterized in that the layer based on titanium oxide comprises an oxidation gradient, the part of the layer based on titanium oxide in contact with the layer based on zinc is more oxidized than the furthest part. Material according to any one of the preceding claims, characterized in that the dielectric coating located above the functional layer comprises a layer based on zinc oxide and tin comprising at least 10% by mass of tin relative to to the total mass of zinc and tin, located above and in contact with the layer based on titanium oxide. Material according to the preceding claim characterized in that the layer based on zinc and tin oxide has a thickness:
- greater than 5 nm,
- less than 40 nm. Material according to any one of the preceding claims, characterized in that the dielectric coating located above the functional layer comprises a layer comprising silicon chosen from layers of silicon nitride or layers of silicon nitride and zirconium. Material according to any one of the preceding claims, characterized in that the dielectric coating located below the functional layer comprises a layer based on zinc oxide located in contact with the functional layer. Material according to any one of the preceding claims, characterized in that the dielectric coating located below the functional layer comprises a layer comprising silicon chosen from layers of silicon nitride or layers of silicon nitride and zirconium. Material according to any one of the preceding claims, characterized in that the dielectric coating located below the functional layer comprises a layer with a refractive index at 550 nm greater than 2.20. 12. Material according to the preceding claim characterized in that the layer with a refractive index greater than 2.20 is chosen from layers based on titanium oxide and layers based on silicon nitride and zirconium. 13. Material according to claim 11 or 12 characterized in that the thickness of all layers with a refractive index greater than 2.20 in the dielectric coating located below the functional layer is greater than 10 nm. Material according to any one of the preceding claims, characterized in that the stack comprises a single functional metallic layer based on silver. 15. Material according to any one of the preceding claims, characterized in that the stack has been subjected to rapid thermal annealing. 16. Material according to any one of claims 1 to 14 characterized in that the stack and the substrate have been subjected to a heat treatment at a high temperature greater than 500 ° C such as quenching, annealing or bending. Process for preparing a material according to any one of claims 1 to 16, the material comprising a substrate coated with a stack of layers comprising at least one functional metallic layer based on silver and at least two dielectric coatings, each dielectric coating comprising at least one dielectric layer, so that each functional metal layer is placed between two dielectric coatings, characterized in that the dielectric coating located above the functional metal layer comprises:
- a layer of zinc deposited in metallic form located in contact with the functional layer and
- a layer based on titanium oxide located above and in contact with the metallic zinc layer.