JP5328649B2 - Quenchable infrared reflective layer system and method for producing the same - Google Patents

Description

  The present invention relates to a quenchable infrared reflective layer system on a transparent substrate having a series of infrared reflective layers formed on a substrate, and a method of manufacturing the same. The series of layers includes at least one selectively functional layer.

  The invention also relates to a method for producing such a layer system, in which a series of infrared reflective layers are formed on a transparent substrate by a suitable method.

  In general, an infrared reflective layer system (low emission (Low-E) layer system) consists of a functional layer, a base layer that improves adhesion of the functional layer, and an anti-reflective coating layer, where individual layers are repeated in the layer system. May be. Usually, a functional layer made of a noble metal (usually silver) or an alloy thereof has good selective reflectivity in the infrared region even if the layer thickness is small. If there is only one functional layer in the layer system, these are often referred to as “Single-Low-E”.

  In addition to antireflection, the coating layer is particularly useful for improving mechanical and chemical durability. It usually consists of a high refractive index, dielectric and silicon containing material. In order to improve the transmission of the layer system in the visible range, this antireflection layer is arranged above and / or below the selectively functional layer.

  In order to cure and / or mold the substrate, such infrared reflective and transparent layer systems are treated in a quenching process. In this case, they are layers that make it possible to heat-treat the substrate supporting the layer system and to keep the changes in the optical, mechanical and chemical properties of the layer system that occur at that time within a certain range. It has a series of layers with properties. This layer system is exposed to different atmospheric conditions for different times in the quenching process, depending on the application of the coated substrate.

  Various phenomena that change the reflectivity of the functional layer and the transmittance of the layer system during the production of the subsequent layer system and during the quenching process due to various thermal loads of the already formed series of layers, in particular Diffusion of the components of the antireflection layer into the functional layer and vice versa occurs. In order to avoid such a diffusion phenomenon, a shielding layer serving as a buffer material for the diffusion component is inserted between the antireflection layer and the functional layer. This shielding layer is structured and arranged to accommodate the resulting heat load and protects the sensitive functional layer or layers that are often very thin from being affected by adjacent layers. By inserting one or more shielding layers, in particular the color shift of the layer system and the increase in surface resistance of the layer system due to the quenching process is reduced.

  In particular, NiCr or NiCrOx layers are known as quenchable layer-based shielding layers. For example, in Patent Document 1 and Patent Document 2, this shielding layer surrounds or protects at least one surface of the silver layer (s). However, the shielding layer reduces the conductivity of the silver layer (s). About 5Ω / Sq. When a silver layer having a surface resistance of 5 nm is deposited and embedded in two NiCrOx-layers, the surface resistance is about 1.5 Ω / Sq. 6.5Ω / Sq. Can be.

  Patent Document 3 describes a layer system in which a silver layer is included as a selective functional layer, and a shielding layer made of nickel or nickel chrome is provided on both sides thereof. There, in the case of a single low emission, the layer system is stabilized during heat treatment by inserting a NiCrOx layer into the functional silver layer. The disadvantage is that for this layer system, each of both silver sublayers must be about 7-8 nm thick to avoid silver sublayer islands (Inselbildung). For this reason, the transmittance of the layer system is low. Further, Patent Document 3 describes the use of an unstoichiometric TiOx layer between the shielding layer and the silver layer, which is the occurrence of so-called haze, i.e. to the functional layer. Reduce the change in the optical properties of the functional layer due to the diffusion process. However, this absorptive TiOx layer oxidizes during heat treatment, where substantial changes in transmittance and pre-adjusted chromaticity coordinate shifts occur.

  Patent Document 4 describes a quenchable layer system in which a NiCrOx layer is provided as a shielding layer on both sides of a silver layer which is a highly sensitive layer. Furthermore, in this layer system, dielectric interface layers are respectively provided above and below the shielding layer. Such a layer has various stabilizing effects on the layer system and also functions as a diffusion barrier during the quenching process.

  Furthermore, Patent Document 4 describes the use of a gradient layer for stabilizing a heat-treatable layer system. The disadvantage in this case is that the SiNx layer is under the shielding layer, so that the electrical surface resistance of the layer system and thus the emissivity is not reduced. This solution also provides a series of layers consisting of a sensitive silver layer and a lower layer and two shielding layers each surrounding each silver layer.

  It is also known from US Pat. No. 6,057,836 to form a metal shielding layer, which forms a gradient layer with the functional layer silver in the transition region between both layers. The antireflection layer can be composed of a plurality of metal oxide layers, and a gradient layer composed of both adjacent single layers exists between the respective layers.

  Since the use of a metal oxide for the antireflection layer is not an optimal solution, the antireflection layer of Patent Document 6 is composed of a plurality of single layers of different metal nitrides, where the ratio of the material of one layer Decreases from the initial 100% to 0% and the proportion of adjacent monolayer materials increases on a scale from 0% to 100%. However, it has been found that the desired transmittance cannot be guaranteed even with this layer system.

  These various types of layer structures are still too sensitive to atmospheric conditions, despite various treatments, and can only be adapted to specific quenching processes, so they are difficult or very different in atmospheric conditions. It has been found that it cannot be produced with sufficient quality or yield.

  Even in the case of raw glass with an indeterminate starting state, i.e. a chemical glass composition that is not particularly constant with respect to the proportion of sodium, this layer system is also a quality problem during manufacture. In addition, the effects of another glass (such as corrosion or traces of suction used to handle glass) that are often not visible by visual inspection and cannot be removed by normal cleaning are undesirable layer systems. Cause changes in the characteristics. If there is such a glass influence, it is particularly disadvantageous that its influence on the properties of the layer system becomes apparent only after the quenching process.

German Patent Invention No. 035 43 178 EP 1 174 379 EP 0 999 192B1 EP 1 238 950 A2 German Patent Invention No. 100 46 810 German Patent Invention No. 101 31 932

  Therefore, the object of the present invention is to provide a sufficient quality under the severe atmospheric conditions of the heat treatment of the substrate and / or under indeterminate conditions in the case of a glass substrate, in particular an adjustable transmittance of about 10-80% in the visible range, As well as providing a layer system and a method for its production which guarantees a low emissivity and at the same time allows a sufficient stability of the chromaticity coordinates of the layer system.

  The object of the present invention is solved by a layer system having the features of claim 1 and a method having the features of claim 23. Advantageous embodiments of the invention are the subject of the dependent claims.

  A hardenable, infrared reflective and absorptive layer system for coating the dielectric substrate (S0) according to the invention can be applied in the following order on the substrate (S0): At least one transparent high refractive index dielectric layer S2, one substrate-side absorption or shielding layer S3, one functional metal reflective layer S4, one upper absorption or shielding layer S5, and one transparent high refraction. It has a dielectric constant layer S6.

  The layer system according to the present invention is a quenchable that can be tuned between about 10% and about 80% of the transmittance of visible light region and the nature of a quenchable IR reflective layer system (low emission) on a glass substrate. It is possible to combine the characteristics of a solar control system.

  Advantageously, the layer S4 consists of silver or a silver alloy.

  According to one embodiment of the present invention, the refractive index of at least one of the layers S2 and S6 is 2.0 to 2.5 for light having a wavelength of 550 nm.

  The layer S2 can then consist of a metal, a semiconductor, or an oxide or nitride of a semiconductor alloy. Furthermore, the layer 6 may comprise silicon.

  In another embodiment of the invention, at least one of the layers S3 and S5 comprises a metal, metal oxide, metal nitride, or alloy.

  Furthermore, at least one of the layers S3 and S5 can comprise chromium or a chromium compound. For example, at least one of the layers S3 and S5 can include CrNx.

  According to another form of the invention, layers S3 and S5 have the same stoichiometric composition and layer thickness (symmetric system) when using the same material.

  Alternatively, layers S3 and S5 may have different stoichiometric compositions and / or layer thicknesses (asymmetric systems) when using the same material.

  In one embodiment of the invention, at least one of the layers S3 and S5 is made of SiOxNy (1.5 <n <2.1), NiCr or NiCr compound (NiCrNx or NiCrNx).

  According to another aspect of the invention, a transparent medium to low refractive index dielectric barrier and / or adhesive layer S1 is disposed between the substrate S0 and the layer S2.

  According to yet another aspect of the invention, a transparent medium to low refractive index dielectric barrier and / or adhesive layer S7 is disposed on the layer S6.

  Advantageously, the refractive index of the layer S1 can be smaller than the refractive index of the layer S2.

  More advantageously, the refractive index of the layer S7 can be smaller than the refractive index of the layer S6.

  Particularly preferably, the refractive index of at least one of the layers S1 and S7 is 1.60 to 1.75 for light with a wavelength of 550 nm.

  Furthermore, the material of at least one of the layers S1 and S7 can be selected such that its refractive index is close to the refractive index of the substrate S0.

  Furthermore, at least one of the layers S1 and S7 can comprise a metal, a semiconductor, or a semiconductor alloy oxynitride. Advantageously, at least one of the layers S1 and S7 comprises silicon oxynitride.

Particularly advantageously, the optical thickness (n ^* d) of S1 is less than λ / 4, where λ is the centroid wavelength of the transparent spectral region.

  According to yet another aspect of the invention, at least one other metallic reflective layer is disposed between the layers S1 and S7.

  Advantageously, the at least one other metallic reflective layer comprises silver.

  The process according to the invention for such a layer system is characterized in that at least one layer is formed by sputtering, preferably by DC- or MF-magnetron sputtering.

  Advantageously, at least one of the layers S1 and S7 is formed by CVD- or a CVD-process using plasma.

  Preferably, at least one of the layers S1 and S7 is formed by reactive magnetron sputtering of silicon or a silicon aluminum alloy in an atmosphere containing oxygen and / or nitrogen.

  Particularly preferably, at least one of the layers S1 and S7 is formed by reactive magnetron sputtering of silicon or a silicon aluminum alloy in an argon atmosphere containing oxygen and / or nitrogen.

  Furthermore, according to the present invention, at least one of the layers S1 and S7 has a different chemistry by reactive magnetron sputtering of silicon or silicon aluminum alloy in an atmosphere containing oxygen and / or nitrogen and / or argon. It is formed as a gradient layer having a stoichiometric composition.

Examples of possible layer systems according to the invention are as follows:
S0 / S1 / Si3N4 / CrNx / Ag / CrNx / Si3N4 / S7
S0 / S1 / Si3N4 / NiCrNx / Ag / CrNx / Si3N4 / S7
S0 / S1 / Si3N4 / CrNx / Ag / NiCrNx / Si3N4 / S7
S0 / S1 / Si3N4 / SiOxNy / Ag / CrNx / Si3N4 / S7

  The layers S3 and S5 function as an absorptive and reflective layer, and the transmittance of the layer system can be adjusted by the thickness. By using Cr or CrNx compounds of different thicknesses in at least one absorption layer to achieve the desired transmittance, the color shift after quenching can be kept very small. Cr or CrNx is an excellent shielding material for protecting the Ag layer. If the Cr or CrNx layer is formed on only one side of the silver, another thin shielding layer must be formed on the other side to protect the Ag layer (eg, SiOxNy, NiCrNx,...). Another advantage of using a Cr or CrNx compound instead of a typical NiCr or NiCr compound (NiCrOx) is that less haze occurs after quenching, otherwise nickel is especially preferred for adjacent layers. Haze is generated by diffusing inside.

  Optional layer S1 is a barrier layer that prevents Na + from diffusing from the glass substrate into the layer system and the influence of the glass on the properties of the layer (such as corrosion or suction means traces). Furthermore, by depositing layer S1, the water brought into the coating apparatus together from the glass substrate is removed from the substrate.

  Similarly, the optional layer S7 becomes an antireflective layer due to its lower refractive index than the normal coating layer S6, which further increases the transmission of the layer system when high transmission is desired. Let

Claims (18)

A hardenable, infrared-reflective and precisely tunable absorptive layer system for coating a dielectric substrate (S0) on the substrate (S0) in the following order in the following order: High refractive index dielectric layer S2, one substrate side absorbing or shielding layer S3, one functional metal reflective layer S4, one upper absorbing or shielding layer S5, and a transparent high refractive index dielectric layer S6 , On this occasion,
The layer S4 is made of silver or a silver alloy,
The refractive index of at least one of the layers S2 and S6 is 2.0 to 2.5 for light having a wavelength of 550 nm,
The layer S2 is made of a metal, semiconductor, or semiconductor alloy oxide or nitride;
The layer S6 contains Si;
One of the layers S3 and S5 comprises CrNx, and
The other of the layers S3 and S5 is made of SiOxNy (1.5 <n <2.1),
A layer system as described above.   The layer system according to claim 1, characterized in that a transparent medium to low refractive index dielectric barrier and / or adhesive layer S1 is arranged between the substrate S0 and the layer S2.   3. Layer system according to claim 1 or 2, characterized in that a transparent medium to low refractive index dielectric barrier and / or an adhesive layer S7 are arranged on the layer S6. The layer system according to any one of claims 1 to 3 , characterized in that the refractive index of the layer S1 is smaller than the refractive index of the layer S2. The layer system according to any one of claims 1 to 4 , characterized in that the refractive index of the layer S7 is smaller than the refractive index of the layer S6. At least one of the refractive index of the layer S1 and S7 is, in the light of a wavelength of 550 nm, characterized in that it is a 1.60 to 1.75, according to any one of claims 1 to 5 Layer system. At least one material of said layers S1 and S7 is characterized in that its refractive index is selected to be close to the refractive index of the substrate S0, according to any one of claims 1 to 6 Layer system. 8. A layer system according to any one of the preceding claims , characterized in that at least one of the layers S1 and S7 comprises an oxynitride of a metal, a semiconductor or a semiconductor alloy. 9. Layer system according to any one of the preceding claims , characterized in that at least one of the layers S1 and S7 comprises silicon oxynitride. The optical thickness (n ^* d) of S1 is smaller than λ / 4, where λ is the centroid wavelength of the transparent spectral region, according to any one of claims 1-9 . Layer system. 11. A layer system according to any one of the preceding claims , characterized in that at least one other metal reflective layer is arranged between the layers S1 and S7. 12. A layer system according to any one of the preceding claims , characterized in that at least one other metallic reflective layer comprises silver. The method for producing a layer system according to claim 1 , wherein at least one layer is formed by sputtering. 14. A method according to claim 13 , characterized in that at least one layer is formed by DC- or MF-magnetron sputtering. 15. A method according to claim 13 or 14 , characterized in that at least one of the layers S1 and S7 is formed by CVD- or a CVD-process using plasma. At least one of the layers S1 and S7, silicon or silicon in an atmosphere containing oxygen and / or nitrogen - characterized in that it is formed by reactive magnetron sputtering of aluminum alloy, according to claim 13 to 15 The method as described in any one of. 14. At least one of the layers S1 and S7 is formed by reactive magnetron sputtering of silicon or a silicon-aluminum alloy in an argon atmosphere containing oxygen and / or nitrogen . The method according to any one of 16 . Gradient layers in which at least one of the layers S1 and S7 has different stoichiometric composition by reactive magnetron sputtering of silicon or silicon-aluminum alloy in an atmosphere containing oxygen and / or nitrogen and / or argon The method according to claim 13 , wherein the method is formed as: