Infrared reflecting layer system for transparent substrate

1. Method for manufacturing an infrared radiation reflecting transparent layer system in which an infrared radiation reflecting layer sequence is deposited by vacuum coating on a transparent substrate, said layer sequence consisting of, as seen from the substrate upward,

a. a first transparent dielectric layer of an oxynitride of a metal, a semiconductor or a semiconductor alloy having a low to moderate refractive index;

b. a second transparent dielectric layer having a high refractive index;

c. a blocking layer;

d. a first interface layer;

e. a selective function layer;

f. an optionally present second interface layer;

g. a second blocking layer;

h. an optionally present third interface layer;

i. a third transparent dielectric layer having a high refractive index and containing silicon; and

j. a fourth transparent dielectric layer of an oxynitride of a metal, a semiconductor or a semiconductor alloy having a low to moderate refractive index.

2. Method according to claim 1 , wherein the refractive index of said first dielectric layer having a low to moderate refractive index is approximately equal to or slightly greater than the refractive index of the substrate.

3. Method according to claim 2 , wherein the refractive index of said first dielectric layer having a low to moderate refractive index is in the range between 1.50 and 1.85 at a main wavelength of visible light of approximately 550 nm.

4. Method according to claim 1 , wherein the refractive index of said fourth dielectric layer having a low to moderate refractive index is between 1.50 and 1.95 at a main wavelength of visible light of approximately 550 nm.

5. Method according to claim 1 , wherein said first and fourth dielectric layers having a low to moderate refractive index have approximately the same refractive index.

6. Method according to claim 1 , wherein the refractive index of at least one of said second and third highly refractive dielectric layers amounts to approximately 1.9 to 2.6 with light of a wavelength of 550 nm.

7. Method according to claim 1 , wherein an oxynitride of silicon is deposited as at least one of said first and fourth dielectric layers having a low to moderate refractive index.

8. Method according to claim 7 , wherein said first dielectric layer having a low to moderate refractive index is deposited with an oxygen and nitrogen content that differs from the oxygen and nitrogen content of said fourth dielectric layer having a low to moderate refractive index.

9. Method according to claim 7 , wherein said first dielectric layer having a low to moderate refractive index is deposited with an oxygen or nitrogen content that differs from the oxygen or nitrogen content of said fourth dielectric layer having a low to moderate refractive index.

10. Method according to claim 1 , wherein at least one of said first and fourth dielectric layers having a low to moderate refractive index is applied by chemical vapor deposition methods (CVD methods) or plasma-supported CVD processes.

11. Method according to claim 1 , wherein at least one of said first and fourth dielectric layers having a low to moderate refractive index is applied by reactive magnetron sputtering of silicon or silicon-aluminum alloys in an atmosphere containing at least one of the gases oxygen and nitrogen.

12. Method according to claim 1 , wherein at least one of said first and fourth dielectric layers having a low to moderate refractive index is deposited as a gradient layer with an oxygen and nitrogen content that decreases toward the function layer.

13. Method according to claim 1 , wherein a transparent second dielectric layer of an oxide or nitride of a metal, a semiconductor or a semiconductor alloy having a high refractive index is deposited directly as a bottom layer of said layer sequence on said first dielectric layer having a low to moderate refractive index.

14. Method according to claim 1 wherein said layer sequence consists of:

a. silicon oxynitride;

b. titanium oxide;

c. nickel chromium oxide;

d. zinc aluminum oxide;

e. silver;

f. optionally present zinc aluminum oxide;

g. nickel chromium oxide;

h. optionally present stannic oxide;

i. silicon nitride; and

j. silicon oxynitride.