Fast heat treatment method for a complete all-solid-state electrochromic stack

1. A process for manufacturing an electrochromic glazing unit comprising:

(a) forming, on one face of a glass sheet, a complete all-solid-state electrochromic stack comprising in succession:

a first layer of a transparent conductive oxide;

a layer of a cathodically colored mineral electrochromic material to form an electrochromic electrode;

a layer of an ionically conductive mineral solid electrolyte;

a layer of a cation intercalation material to form a counter electrode; and

a second layer of a transparent conductive oxide; and

(b) performing a heat treatment of the complete electrochromic stack by irradiation with radiation having a wavelength comprised between 500 and 2000 nm, said radiation originating from a radiating device placed facing the electrochromic stack, a relative movement being created between said radiating device and said glass sheet so as to raise the electrochromic stack to a temperature at least equal to 300° C. for a duration shorter than 100 milliseconds,

wherein the temperature of a face of said glass sheet which is opposite said one face does not exceed 100° C. during the heat treatment.

2. The process as claimed in claim 1 , wherein the forming of the complete all-solid-state electrochromic stack in step (a) comprises, before performing said heat treatment in step (b), carrying out a final annealing of the complete all-solid-state electrochromic stack in an annealing lehr.

3. The process as claimed in claim 1 , wherein the transparent conductive oxide forming the first and second transparent conductive oxide layers is chosen from the group formed by mixed indium tin oxide (ITO) and aluminum- and/or gallium-doped zinc oxide.

4. The process as claimed in claim 1 , wherein the cathodically colored mineral electrochromic material of the electrochromic electrode is tungsten oxide (WO x ).

5. The process as claimed in claim 1 , wherein the cation intercalation material of the counter electrode is chosen from the group formed by mixed tungsten nickel oxide and iridium oxide.

6. The process as claimed in claim 1 , wherein the ionically conductive mineral solid electrolyte is chosen from the group formed by silica, tantalum oxide and niobium oxide.

7. The process as claimed in claim 1 , wherein the radiating device is a laser.

8. The process as claimed in claim 1 , wherein the radiating device is a flash lamp.

9. The process as claimed in claim 1 , wherein all thin layers of the electrochromic stack are deposited by magnetron sputtering.

10. The process as claimed in claim 2 , wherein the final annealing is at a temperature comprised between 350 and 450° C.

11. The process as claimed in claim 10 , wherein the final annealing is at a temperature between 370 and 410° C.

12. The process as claimed in claim 1 , wherein the temperature of the face of said glass sheet which is opposite said one face does not exceed 50° C. during the heat treatment.

13. The process as claimed in claim 12 , wherein the temperature of the face of said glass sheet which is opposite said one face does not exceed 30° C. during the heat treatment.

14. The process as claimed in claim 7 , wherein the laser is configured to emit a laser beam forming at the electrochromic stack a line covering an entire width of the electrochromic stack.

15. The process as claimed in claim 1 , wherein the heat treatment of the complete electrochromic stack by irradiation is performed in step (b) without carrying out a final annealing, between step (a) and step (b), of the complete all-solid-state electrochromic stack in an annealing lehr.

16. The process as claimed in claim 7 , wherein an axis of propagation of a laser line emitted by the laser makes a nonzero angle with the normal to the glass sheet.

17. The process as claimed in claim 16 , wherein the angle is between 5° and 20° .