Manufacturing method of semiconductor device including stepping structure and supporting structure

1. A method of manufacturing a semiconductor device, the method comprising:

forming a first patterned stack structure including a cell region, a first portion in a first contact region, and a second portion in a second contact region, the second portion of the first patterned stack structure including a first opening;

forming a second patterned stack structure including a third portion over the cell region and the second contact region of the first patterned stack structure;

forming a second opening penetrating the third portion of the second patterned stack structure, the second opening being coupled to the first opening; and

forming a third opening penetrating the first portion of the first patterned stack structure when the second opening is formed,

wherein a diameter of a top of the third opening is greater than a diameter of a top of the second opening.

2. The method of claim 1 , further comprising:

forming a sacrificial pattern in the first opening;

removing the sacrificial pattern, after the second opening and the third opening are formed; and

forming a first supporting structure in the third opening; and

forming a second supporting structure in the first and second openings when the first supporting structure is formed.

3. The method of claim 1 , further comprising:

forming a first plug in the first opening;

forming a second plug coupled to the first plug in the second opening; and

forming a first supporting structure in the third opening when the second plug is formed.

4. The method of claim 1 , further comprising:

forming a first stack structure;

forming a second initial stack structure over the first stack structure; and

patterning the second initial stack structure and the first stack structure to form a second stack structure and a first intermediate stack structure, respectively, before the second opening is formed,

wherein the first intermediate stack structure has a first stepped shape and the second stack structure has a second stepped shape.

5. The method of claim 4 , wherein the first intermediate stack structure in the first contact region has the first stepped shape, and the second stack structure in the second contact region has the second stepped shape.

6. The method of claim 1 , wherein the third opening has a depth deeper than that of the second opening.

7. The method of claim 4 , further comprising forming an insulating layer over the second stack structure,

wherein the second opening penetrates the insulating layer and the third portion of the second patterned stack structure, and the third opening penetrates the insulating layer and the first portion of the first patterned stack structure.

8. The method of claim 1 , further comprising:

forming a mask pattern over the second patterned stack structure, the mask pattern covering the second opening and exposing the third opening, after the second and third openings are formed; and

etching the first patterned stack structure, using the mask pattern as an etch barrier until the third opening reaches or extends beyond a lower surface of the first patterned stack structure.

9. The method of claim 1 , further comprising:

forming a fourth opening penetrating a first stack structure in the cell region when the first opening is formed; and

forming a fifth opening penetrating the second patterned stack structure in the cell region when the second and third openings are formed, the fifth opening being coupled to the fourth opening.

10. The method of claim 9 , wherein the first opening has a diameter greater than that of the fourth opening.

11. The method of claim 9 , wherein the second opening has a first diameter and the third opening has a second diameter, and each of the first and second diameters is greater than that of the fifth opening.

12. The method of claim 9 , further comprising forming a channel structure in the fourth and fifth openings.

13. The method of claim 12 , further comprising forming a first supporting structure in the third opening and a second supporting structure in the first and second openings, when the channel structure is formed in the fourth and fifth openings.

14. The method of claim 9 , further comprising:

forming a protective layer filling the fifth opening, the protective layer exposing the third opening; and

etching the first patterned stack structure using the protective layer as an etch barrier until the third opening reaches or extends beyond a lower surface of the first patterned stack structure.

15. The method of claim 14 , wherein the protective layer includes amorphous carbon.

16. The method of claim 1 , further comprising forming a sacrificial pattern in the first opening,

wherein the second opening is formed to have a sufficient depth to expose a top portion of the sacrificial pattern.