Metal mask manufacturing method and metal mask
A metal mask manufacturing method includes: (a) disposing a first anti-etching layer having a first void region on a first face of a substrate; (b) disposing a second anti-etching layer on a second face of the substrate opposite to the first face, wherein a second void region of the second anti-etching layer is corresponding to the first void region; (c) performing a first etching on the first face and the second face to form a first concave part and a second concave part separated by a part of the substrate; (d) disposing a protecting layer filled into the first concave part; (e) performing a second etching from the second face to produce a void between the first concave part and the second concave part; (f) removing the second anti-etching layer; and (g) performing a third etching from the second face.
1. A metal mask manufacturing method, comprising:
(a) disposing a first anti-etching layer having a first void region on a first face of a substrate;
(b) disposing a second anti-etching layer on a second face of the substrate opposite to the first face, wherein a second void region of the second anti-etching layer is corresponding to the first void region;
(c) performing a first etching on the first face and the second face to respectively form a first concave part on the first face at the area exposed by the first void region and a second concave part on the second face at the area exposed by the second void region, wherein the first concave part and the second concave part are separated by a portion of the substrate;
(d) disposing a protecting layer filled into the first concave part;
(e) performing a second etching from the second face to produce a void between the first concave part and the second concave part;
(f) removing the second anti-etching layer; and
(g) performing a third etching from the second face.
2. The method of claim 1 , wherein the step (b) includes making the lateral width of the second void region larger than the lateral width of the first void region.
3. The method of claim 2 , wherein in the step (g), a micro structure wall is formed by etching the inner wall of the second void region, wherein the third etching is stopped when the angle between the micro structure wall and the first face is smaller than 40 degrees.
4. The method of claim 3 , wherein in the step (g) the third etching is stopped when the curvature radius of the micro structure wall is larger than 500 μm.
5. The method of claim 2 , wherein the step (e) includes stopping the second etching when the lateral width of the void is close to the maximum lateral width of the first concave part.
6. The method of claim 5 , wherein in the step (g), a micro structure wall is formed by etching the inner wall of the second void region, wherein the third etching is stopped when the angle between the micro structure wall and the first face is smaller than 40 degrees.
7. The method of claim 6 , wherein in the step (g) the third etching is stopped when the curvature radius of the micro structure wall is larger than 500 μm.
8. The method of claim 1 , wherein the step (e) includes stopping the second etching when the lateral width of the void is close to the maximum lateral width of the first concave part.
9. The method of claim 8 , wherein in the step (g), a micro structure wall is formed by etching the inner wall of the second void region, wherein the third etching is stopped when the angle between the micro structure wall and the first face is smaller than 40 degrees.
10. The method of claim 9 , wherein in the step (g) the third etching is stopped when the curvature radius of the micro structure wall is larger than 500 μm.
11. The method of claim 1 , wherein in the step (g), a micro structure wall is formed by etching the inner wall of the second void region, wherein the third etching is stopped when the angle between the micro structure wall and the first face is smaller than 40 degrees.
12. The method of claim 11 , wherein in the step (g) the third etching is stopped when the curvature radius of the micro structure wall is larger than 500 μm.
13. A metal mask manufactured by the method of claim 1 , wherein the metal mask includes a plurality of micro structures, the adjacent micro structures have a gap; wherein each micro structure comprises:
a bottom face being a part of the first face; and
at least a micro structure wall, wherein the angle between the micro structure wall and the bottom face is smaller than 40 degrees.
14. The metal mask of claim 13 , wherein the angle between the micro structure wall and the bottom face is larger than 20 degrees.
15. The metal mask of claim 13 , wherein the curvature radius of the micro structure wall is larger than 500 μm.
16. The metal mask of claim 13 , wherein the lateral width of the gap is not less than half of the lateral width of the bottom face.
17. The method of claim 1 , wherein the third etching of the step (g) includes a sputter etching facing to the second face.