Systems and methods for thermal processing of a substrate
Various materials can be deposited on an OLED substrate at various steps, in which the materials may subsequently require drying, baking and a combination thereof. Given the critical nature of drying and baking steps, the inventors of the present teachings have designed various modules for carrying out drying and baking which can be used as a process development module, and additionally for as a dedicated process module in production.
1. A method for processing a substrate comprising:
coating a liquid ink on a substrate, wherein the liquid ink is a formulation comprising a carrier liquid and a film-forming material;
positioning the substrate in a drying chamber of a drying module, wherein the drying chamber comprises
a substrate support apparatus for supporting the substrate,
a condensation plate positioned above the substrate support apparatus, wherein a surface of the condensation plate opposing the substrate is configured to provide at least two gap distances between the surface of the condensation plate opposing the substrate and the substrate, and
wherein a first gap distance of the at least two gap distances is positioned over a first area on the substrate, and a second gap distance of the at least two gap distances is positioned over a second area on the substrate;
applying a vacuum to the drying chamber; and
drying the substrate in the drying chamber;
wherein the method further comprises before or during drying the substrate, controlling the temperature of the substrate and the condensation plate; and
wherein the temperature of the condensation plate is controlled in a range of between about −10° C. to about 15° C.
2. The method of claim 1 , wherein a controlled temperature of the substrate is maintained relative to a controlled temperature of the condensation plate.
3. The method of claim 2 , wherein the controlled temperature of the substrate is maintained at a higher temperature than the controlled temperature of the condensation plate.
4. The method of claim 1 , wherein controlling the temperature of the substrate is done by controlling the temperature of the substrate support apparatus.
5. The method of claim 1 , wherein controlling the temperature of the substrate is done by controlling a remote heating method.
6. The method of claim 1 , wherein the remote heating method is a method using an infra-red source for heating the substrate.
7. The method of claim 1 , wherein the temperature of the substrate is controlled in a range of between about 40° C. to about 300° C.
8. The method of claim 1 , wherein the first region of the substrate that has a carrier liquid vapor concentration that is uniform over the first region.
9. The method of claim 8 , wherein the first gap between the condensation plate and the first region of the substrate is about 1 millimeter to about 20 millimeters.
10. The method of claim 1 , wherein the vacuum applied to the drying chamber during drying is less than or equal to about 1×10 −5 Torr.
11. The method of claim 1 , wherein the drying module further comprises edge shields positioned proximal to the substrate.
12. A method for processing a substrate comprising:
coating a liquid ink on a substrate, wherein the liquid ink is a formulation comprising a carrier liquid and a film-forming material;
positioning the substrate in a drying chamber of a drying module, wherein the drying chamber comprising
a substrate support apparatus for supporting the substrate,
a condensation plate positioned above the substrate support apparatus, wherein a surface of the condensation plate opposing the substrate is configured to provide at least two gap distances between the surface of the condensation plate opposing the substrate and the substrate, and
wherein a first gap distance of the at least two gap distances is positioned over a first area on the substrate, and a second gap distance of the at least two gap distances is positioned over a second area on the substrate;
applying a vacuum to the drying chamber;
drying the substrate in the drying chamber;
wherein the second region of the substrate has a carrier liquid vapor concentration that is non-uniform over the second region.
13. The method of claim 12 , wherein the second gap between the condensation plate and the second region of the substrate is greater than the first gap by at least 1 millimeter.
14. The method of claim 12 , further comprising before or during drying the substrate, controlling the temperature of the substrate and the condensation plate.
15. The method of claim 14 , wherein a controlled temperature of the substrate is maintained relative to a controlled temperature of the condensation plate.
16. The method of claim 15 , wherein the controlled temperature of the substrate is maintained at a higher temperature than the controlled temperature of the condensation plate.
17. The method of claim 14 , wherein controlling the temperature of the substrate is done by controlling the temperature of the substrate support apparatus.
18. The method of claim 14 , wherein controlling the temperature of the substrate is done by controlling a remote heating method.
19. The method of claim 14 , wherein the remote heating method is a method using an infra-red source for heating the substrate.
20. The method of claim 14 , wherein the temperature of the substrate is controlled in a range of between about 40° C. to about 300° C.
21. The method of claim 14 , wherein the temperature of the condensation plate is controlled in a range of between about −10° C. to about 15° C.
22. The method of claim 12 , wherein the first region of the substrate that has a carrier liquid vapor concentration that is uniform over the first region.
23. The method of claim 22 , wherein the first gap between the condensation plate and the first region of the substrate is about 1 millimeter to about 20 millimeters.
24. The method of claim 12 , wherein the vacuum applied to the drying chamber during drying is less than or equal to about 1×10 −5 Torr.
25. The method of claim 12 , wherein the drying module further comprises edge shields positioned proximal to the substrate.