Methods of manufacturing pellicle assembly and photomask assembly

1. A method of manufacturing a pellicle assembly, the method comprising:

forming a sublimable support layer on a first surface of a pellicle membrane;

attaching a pellicle frame to a second surface of the pellicle membrane while the sublimable support layer is on the first surface of the pellicle membrane, the second surface of the pellicle membrane being opposite to the first surface of the pellicle membrane; and

sublimating the sublimable support layer while the pellicle frame is attached to the pellicle membrane to remove the sublimable support layer from the pellicle membrane.

2. The method of claim 1 , wherein the sublimable support layer comprises a hydrocarbon compound.

3. The method of claim 1 , wherein the sublimable support layer comprises an inorganic material.

4. The method of claim 1 , wherein forming the sublimable support layer comprises supplying a gaseous sublimable material onto the first surface of the pellicle membrane.

5. The method of claim 1 , wherein forming the sublimable support layer comprises coating a liquid sublimable material onto the first surface of the pellicle membrane.

6. The method of claim 1 , further comprising forming a polymer layer having viscoelasticity on a portion of the first surface of the pellicle membrane prior to forming the sublimable support layer,

wherein forming the sublimable support layer comprises forming the sublimable support layer on the first surface of the pellicle membrane and on the polymer layer, and the polymer layer is between the sublimable support layer and the pellicle membrane.

7. The method of claim 1 , wherein forming the sublimable support layer comprises forming the sublimable support layer to have a first thickness on a center region of the pellicle membrane and a second thickness that is greater than the first thickness on an edge region of the pellicle membrane surrounding the center region of the pellicle membrane.

8. The method of claim 1 , wherein forming the sublimable support layer comprises:

forming a first sublimable support layer on a first portion of the first surface of the pellicle membrane; and

forming a second sublimable support layer on a second portion of the first surface of the pellicle membrane and on the first sublimable support layer, wherein the first portion of the first surface of the pellicle membrane is different from the second portion of the first surface of the pellicle membrane, and the first sublimable support layer is between the pellicle membrane and the second sublimable support layer.

9. The method of claim 8 , wherein a first density of the first sublimable support layer is greater than a second density of the second sublimable support layer.

10. The method of claim 1 , wherein a metal-containing thin film is on the second surface of the pellicle membrane while forming the sublimable support layer on the first surface of the pellicle membrane, and

wherein the method further comprises removing the metal-containing thin film from the pellicle membrane to expose the second surface of the pellicle membrane after forming the sublimable support layer and before attaching the pellicle frame to the second surface of the pellicle membrane.

11. The method of claim 1 , wherein removing the sublimable support layer comprises sublimating the sublimable support layer at room temperature and atmospheric pressure.

12. The method of claim 1 , wherein removing the sublimable support layer comprises sublimating the sublimable support layer under an alcohol atmosphere.

13. A method of manufacturing a pellicle assembly, the method comprising:

forming a pellicle membrane on a metal-containing thin film, the pellicle membrane comprising a first surface and a second surface that is opposite to the first surface and comprising an edge portion and a center portion surrounded by the edge portion;

forming a sublimable support layer on the first surface of the pellicle membrane, the sublimable support layer having a first thickness on the edge portion of the pellicle membrane and a second thickness on the center portion of the pellicle membrane, and the first thickness being different from the second thickness;

removing the metal-containing thin film from the pellicle membrane;

attaching a pellicle frame to the second surface of the edge portion of the pellicle membrane; and

sublimating the sublimable support layer while the pellicle frame is attached to the pellicle membrane.

14. The method of claim 13 , wherein forming the sublimable support layer comprises:

forming a first sublimable support layer on the first surface of the edge portion of the pellicle membrane, wherein the first sublimable support layer exposes the first surface of the center portion of the pellicle membrane; and

forming a second sublimable support layer on the first surface of the center portion of the pellicle membrane and on the first sublimable support layer, wherein the first sublimable support layer is between the pellicle membrane and the second sublimable support layer.

15. The method of claim 14 , wherein forming the first sublimable support layer is performed at a first pressure, and

wherein forming the second sublimable support layer is performed at a second pressure that is higher than the first pressure.

16. The method of claim 14 , wherein forming the first sublimable support layer comprises:

forming a mask layer on the first surface of the center portion of the pellicle membrane, the mask layer exposing the first surface of the edge portion of the pellicle membrane;

forming a preliminary first sublimable support layer on the mask layer and on the first surface of the edge portion of the pellicle membrane; and

forming the first sublimable support layer by removing the mask layer and a portion of the preliminary first sublimable support layer formed on the mask layer.

17. The method of claim 14 , wherein the first sublimable support layer has a first density that is higher than a second density of the second sublimable support layer.

18. The method of claim 13 , further comprising forming a polymer layer having viscoelasticity on the first surface of the pellicle membrane prior to forming the sublimable support layer,

wherein forming the sublimable support layer comprises forming the sublimable support layer on the first surface of the pellicle membrane and on the polymer layer, and the polymer layer is between the pellicle membrane and the sublimable support layer.

19. A method of manufacturing a photomask assembly, the method comprising:

forming a sublimable support structure comprising a sublimable material on a first surface of a pellicle membrane;

attaching a pellicle frame onto a second surface of the pellicle membrane while the sublimable support structure is on the first surface of the pellicle membrane, the second surface of the pellicle membrane being opposite to the first surface of the pellicle membrane;

sublimating the sublimable material from the sublimable support structure to expose the first surface of the pellicle membrane; and

fixing a photomask to the pellicle frame, the photomask facing the pellicle membrane, and the pellicle frame being between the photomask and the pellicle membrane.

20. The method of claim 19 , wherein the pellicle membrane comprises a center portion and an edge portion surrounding the center portion,

wherein the method further comprises forming a polymer layer having viscoelasticity on the first surface of the edge portion of the pellicle membrane, and

wherein forming the sublimable support structure comprises forming the sublimable support structure on the center portion of the first surface of the pellicle membrane and on the polymer layer, and the polymer layer is between the pellicle membrane and the sublimable support structure.