Mask structure, semiconductor structure and methods for manufacturing same

1. A method for manufacturing a mask structure, comprising:

forming a laminated structure comprising a first dielectric layer, a first mask layer, a second dielectric layer and a second mask layer sequentially stacked from bottom to top, the laminated structure comprising an array region and a periphery region outside the array region;

patterning the second mask layer in the array region and the second dielectric layer in the array region, to form a pattern structure in the array region, the pattern structure exposing the first mask layer;

forming a first mask pattern on side walls of the pattern structure, and removing the pattern structure based on the first mask pattern;

forming a first patterned photoresist layer, the first patterned photoresist layer covering the array region and covering the first mask pattern;

removing the second mask layer in the periphery region, to expose the second dielectric layer in the periphery region;

forming a third dielectric layer, the third dielectric layer covering the second dielectric layer in the periphery region and an upper surface of the first patterned photoresist layer; and

flattening an obtained structure, so that an upper surface of a remaining part of the first patterned photoresist layer and an upper surface of a remaining part of the second dielectric layer are flush with an upper surface of the first mask pattern.

2. The method according to claim 1 , wherein the forming a first mask pattern on side walls of the pattern structure comprises:

forming a first mask material layer on the side walls of the pattern structure, an upper surface of the pattern structure, an upper surface of the first mask layer exposed in the array region, and an upper surface of the second mask layer in the periphery region; and

removing the first mask material layer on the upper surface of the pattern structure and the upper surface of the first mask layer exposed in the array region, to form the first mask pattern on the side walls of the pattern structure; the first mask material layer in the periphery region being retained after the first mask pattern is formed.

3. The method according to claim 2 , wherein the removing the first mask material layer on the upper surface of the pattern structure and the upper surface of the first mask layer exposed in the array region, to form the first mask pattern on the side walls of the pattern structure comprises:

forming a second photoresist layer, the second photoresist layer covering an upper surface of the first mask material layer, and an upper surface of the second photoresist layer being higher than the upper surface of the first mask material layer;

patterning the second photoresist layer, and removing the second photoresist layer in the array region, to obtain a second patterned photoresist layer, the second patterned photoresist layer covering an upper surface of the first mask material layer in the periphery region; and

removing the first mask material layer on the upper surface of the pattern structure and the upper surface of the first mask layer exposed in the array region, to form the first mask pattern on the side walls of the pattern structure.

4. The method according to claim 3 , wherein before the forming a first patterned photoresist layer, the method further comprises: removing the second patterned photoresist layer.

5. The method according to claim 3 , wherein the forming a first patterned photoresist layer comprises:

forming a first photoresist layer, the first photoresist layer covering the array region and the periphery region; and

patterning the first photoresist layer and removing the first photoresist layer in the periphery region, to obtain the first patterned photoresist layer, the upper surface of the first patterned photoresist layer being higher than the upper surface of the first mask pattern and an upper surface of the second dielectric layer.

6. The method according to claim 5 , wherein the first photoresist layer and the second photoresist layer are both negative photoresist layers.

7. The method according to claim 2 , wherein before the removing the second mask layer in the periphery region, the method further comprises: removing the first mask material layer in the periphery region.

8. The method according to claim 1 , wherein an etching selection ratio of the second mask layer to the first mask layer is greater than 1.

9. The method according to claim 1 , wherein an etching selection ratio of the first mask pattern to the first mask layer is greater than 1.

10. The method according to claim 1 , wherein the obtained structure is flattened by using a flat push etching process, so that the upper surface of the remaining part of the first patterned photoresist layer and the upper surface of the remaining part of the second dielectric layer are flush with the upper surface of the first mask pattern.

11. The method according to claim 1 , wherein the first mask pattern extends in a first direction; after the flattening an obtained structure, the method further comprises: forming a second mask pattern on the first mask pattern, the second mask pattern extending in a second direction, and the second direction intersecting the first direction.

12. The method according to claim 11 , wherein after the forming a second mask pattern on the first mask pattern, the method further comprises: patterning the first mask layer and the first dielectric layer based on the second mask pattern and the first mask pattern, to obtain a target mask pattern.

13. A method for manufacturing a semiconductor structure, comprising:

providing a substrate;

forming a material layer to be etched on the substrate;

manufacturing the target mask pattern on an upper surface of the material layer to be etched by using the method according to claim 12 ; and

etching the material layer to be etched based on the target mask pattern, to obtain the semiconductor structure.

14. A semiconductor structure, manufactured by the method according to claim 13 .

15. A mask structure, manufactured by the method according to claim 1 .