Method of collapse-free drying of high aspect ratio structures

1. A method, for drying an etched layer with a plurality of structures, with etched spaces between the plurality of structures, comprising:

providing a liquid within the etched spaces on the etched layer;

displacing the liquid with a drying solution including a solvent;

removing some of the solvent from the drying solution to form a solid from the solution, wherein the solid at least fills half the height of the etched spaces; and

subsequently removing the solid using downstream plasma ashing.

2. The method, as recited in claim 1 , wherein the solid completely fills the etched spaces.

3. The method, as recited in claim 2 , wherein the removing some of the solvent is by either spinning or heating, or both.

4. The method, as recited in claim 3 , wherein the solid is removed by a combination of the downstream plasma ashing and UV degradation.

5. The method, as recited in claim 4 , wherein the solid is either a crystalline, amorphous glass, or a material with a viscosity greater than 1 cP.

6. The method, as recited in claim 5 , wherein the removing the solid has an infinite selectivity with respect to the etched layer material.

7. The method, as recited in claim 6 , wherein the solid does not chemically react with the etched layer material.

8. The method, as recited in claim 7 , wherein the solid overfills the etched spaces between the plurality of structures.

9. The method, as recited in claim 8 , wherein the height of the etched spaces is at least 20 nm.

10. The method, as recited in claim 9 , wherein the solvent is at least one of water or an organic solution and wherein the solution further comprises a polymer forming component.

11. The method, as recited in claim 1 , wherein the etch layer is a silicon or metal based layer.

12. The method, as recited in claim 1 , wherein at least some of the plurality of structures have an aspect ratio of at least 10:1.

13. The method, as recited in claim 1 , wherein the removing some of the solvent is by either spinning or heating, or both.

14. The method, as recited in claim 1 , wherein the solid is removed by ashing or UV degradation, or both.

15. The method, as recited in claim 1 , wherein the solid is either a crystalline, amorphous glass, or a material with a viscosity greater than 1 cP.

16. The method, as recited in claim 1 , wherein the solid does not chemically react with the etched layer material.

17. The method, as recited in claim 1 , wherein the height of the etched spaces is at least 20 nm.

18. The method, as recited in claim 1 , wherein the solvent is at least one of water or an organic solution and wherein the solution further comprises a polymer forming component.

19. An apparatus for drying a wet substrate, comprising:

a chamber for receiving the wet substrate, the wet substrate including:

(i) an etched layer with:

(a) a plurality of structures; and

(b) etched spaces between the plurality of structures; and

(ii) a liquid disposed within the etched spaces on the etched layer;

a wet transfer station for transferring the wet substrate into the chamber;

an electrostatic chuck (ESC) for supporting and electrostatically clamping the wet substrate within the chamber;

a bracing drying solution source;

a bracing drying solution source dispenser dispensing bracing drying solution from the bracing drying solution source to the wet substrate, the bracing drying solution displacing the liquid and including a solvent;

a motor spinning the substrate to remove some of the solvent of the bracing drying solution, removal of the solvent of the bracing drying solution forming a solid from the bracing drying solution, wherein the solid at least fills half the height of the etched spaces;

a downstream plasma source providing a downstream plasma into the chamber to remove the solid via downstream plasma ashing;

a temperature controller for controlling the temperature of the substrate; and

a vacuum pump in fluid connection with the chamber.