Transparent substrate coated with at least one thin layer

Abstract

A transparent glass substrate ( 1, 1′, 1 ″) coated with one or more thin layers ( 6, 16, 28 ) is disclosed, wherein the thin layer most distant from the glass substrate is a composition comprising silicon nitride, carbonitride, oxynitride or oxycarbonitride, said thin layer most distant from the glass substrate being covered by a second layer ( 7, 17 ) which protects against high-temperature corrosion.

1 . A transparent glass substrate ( 1 ,  1 ′,  1 ″) coated with one or more thin layers ( 6 ,  16 ,  28 ), wherein the thin layer most distant from the glass substrate is a composition comprising silicon nitride, said thin layer most distant from the glass substrate being covered by a second layer ( 7 ,  17 ) which protects against high-temperature corrosion, wherein the composition comprising silicon nitride forms part of a stack of thin layers and is deposited on top of at least one functional layer ( 4 ,  10 ,  14 ,  20  and  25 ) having thermal properties or having electrically-conductive properties which comprises a metal, a metal-nitride, a doped-metal-oxide, or mixtures thereof. 
   
   
       2 . The substrate according to  claim 1 , wherein the second layer ( 7 ,  17 ) is deposited in the form of a metal or in the form of a metal oxide which is substoichiometric in terms of oxygen, and is intended to be completely oxidized during a subsequent heat treatment. 
   
   
       3 . The substrate according to  claim 2 , wherein the second layer has a thickness of at most 10 nm. 
   
   
       4 . The substrate according to  claim 1 , wherein the second layer ( 7 ,  17 ) is a metal oxycarbide or oxynitride. 
   
   
       5 . The substrate according to  claim 4 , wherein the second layer has a thickness of at most 20 nm. 
   
   
       6 . The substrate according to  claim 1 , wherein the second layer ( 7 ,  17 ) comprises at least one metal whose oxide is capable of blocking or absorbing corrosive species comprising Na 2 0 at high temperature. 
   
   
       7 . The substrate according to  claim 1 , wherein said functional layer ( 4 ,  10 ,  14 ,  20 ,  25 ) comprises a metal. 
   
   
       9 . The substrate according to  claim 1 , wherein said functional layer ( 4 ,  10 ,  14 ,  20 ,  25 ) comprises a metal-nitride. 
   
   
       10 . The substrate according to  claim 1 , wherein said functional layer ( 4 ,  10 ,  14 ,  20 ,  25 ) comprises a doped-metal-oxide. 
   
   
       11 . The substrate according to  claim 7 , wherein the substrate is provided with a stack of thin layers comprising at least one silver-based layer ( 4 ) deposited, between an inner dielectric coating ( 2 ,  3 ) and an outer dielectric coating ( 6 ) wherein said outer dielectric coating comprises the silicon nitride layer ( 6 ). 
   
   
       12 . The substrate according to  claim 1 , wherein the stack of thin layers comprises at least two functional layers. 
   
   
       13 . The substrate according to  claim 1 , wherein the second layer is effective to protect against high-temperature corrosion to prevent deterioration of the thin layer most distant from the glass substrate during heat treatments for bending or toughening in an atmosphere containing corrosive species 
   
   
       14 . The substrate according to  claim 6 , wherein the metal is selected from the group consisting of Nb, Sn, Ta, Ti, Zr, and mixtures thereof. 
   
   
       15 . The substrate according to  claim 7 , wherein the metal is selected from the group consisting of silver, gold, aluminum, nickel, chromium, stainless steel, and mixtures thereof. 
   
   
       16 . The substrate according to claim  8 , wherein the metal-nitride is selected from the group consisting of TiN, CrN, NbN, ZrN, and mixtures thereof. 
   
   
       17 . The substrate according to  claim 9  wherein the doped-metal-oxide is selected from the group consisting of ITO, F:Sn02, In:ZnO, F:ZnO, Al:ZnO, Sn:ZnO, and mixtures thereof. 
   
   
       18 . The substrate according to  claim 3 , wherein the second layer has a thickness of between 1 and 5 nm. 
   
   
       19 . The substrate according to  claim 5 , wherein the layer ( 7 ,  17 ) deposited in the form of a metal oxide, oxycarbide or oxynitride has a thickness of between 2 and 10 nm. 
   
   
       20 . The substrate according to  claim 1 , wherein the thin layer most distant from the glass substrate is a composition consisting essentially of silicon carbonitride. 
   
   
       21 . The substrate according to  claim 1 , wherein the thin layer most distant from the glass substrate is a composition consisting essentially of silicon oxynitride. 
   
   
       22 . The substrate according to  claim 1 , wherein the thin layer most distant from the glass substrate is a composition consisting essentially of silicon oxycarbonitride.