Mask sheet and manufacturing method for the same

1. A method for manufacturing a mask sheet, the method comprising:

preparing a base sheet comprising an alloy of nickel and iron;

performing a heat treatment on the entire base sheet; and

forming one or more openings in the heat-treated base sheet,

wherein the heat treatment is performed at a temperature in a range from about 520° C. to about 580° C. for about one hour to about two hours.

2. The method of claim 1 , wherein the heat treatment is performed under a nitrogen and hydrogen atmosphere, and

a ratio of the nitrogen and the hydrogen is about 95:5 to about 99:1.

3. The method of claim 1 , wherein a content of the nickel in the alloy is in a range from about 33 wt % to about 37 wt %.

4. The method of claim 1 , wherein the preparing the base sheet comprises forming the base sheet by electroforming.

5. The method of claim 1 , wherein the forming the one or more openings is performed by laser radiation.

6. The method of claim 1 , wherein the preparing the base sheet comprises preparing the base sheet having a thickness of about 30 μm or less.

7. The method of claim 1 , wherein the preparing the base sheet comprises preparing the base sheet in which a crystal structure of the alloy comprises a polycrystalline structure.

8. The method of claim 1 , wherein a crystal structure of the alloy in the heat-treated base sheet comprises a single crystalline structure.

9. The method of claim 8 , wherein the single crystalline structure has only a face centered cubic structure.

10. The method of claim 1 , wherein a size of crystal grains in a crystal structure in the heat-treated base sheet is in micro-scale.