阅读说明：本技术 三维半导体器件 (Three-dimensional semiconductor device ) 是由 郑煐陈 印炯烈 曹诚汉 于 2019-05-30 设计创作，主要内容包括：一种三维半导体器件包括经过第一沟道结构和第二沟道结构之间以及第一虚设沟道结构和第二虚设沟道结构之间的公共源极线,其中公共源极线和第一沟道结构之间在第一方向上的距离等于公共源极线和第二沟道结构之间在第一方向上的距离,并且公共源极线和第一虚设沟道结构之间在第一方向上的距离不同于公共源极线和第二虚设沟道结构之间在第一方向上的距离。(A three-dimensional semiconductor device includes a common source line passing between a first channel structure and a second channel structure and between a first dummy channel structure and a second dummy channel structure, wherein a distance between the common source line and the first channel structure in a first direction is equal to a distance between the common source line and the second channel structure in the first direction, and the distance between the common source line and the first dummy channel structure in the first direction is different from the distance between the common source line and the second dummy channel structure in the first direction.)

1. A three-dimensional semiconductor device comprising:

a substrate;

a stacked structure disposed on the substrate, the stacked structure including a cell region and a pad region;

a first channel structure penetrating the cell region;

a second channel structure penetrating the cell region and spaced apart from the first channel structure in a first direction;

a first dummy channel structure penetrating the pad region;

a second dummy channel structure penetrating the pad area and spaced apart from the first dummy channel structure in the first direction; and

a common source line passing between the first channel structure and the second channel structure and between the first dummy channel structure and the second dummy channel structure,

wherein a distance between the common source line and the first channel structure in the first direction is equal to a distance between the common source line and the second channel structure in the first direction, an

A distance in the first direction between the common source line and the first dummy channel structure is different than a distance in the first direction between the common source line and the second dummy channel structure.

2. The three-dimensional semiconductor device of claim 1, wherein the common source line is closer to one of the first and second dummy channel structures that is farther from a central plane that extends in a second direction perpendicular to the first direction and parallel to a third direction perpendicular to a major surface of the substrate and bisects the stacked structure.

3. The three-dimensional semiconductor device of claim 1, wherein the first and second channel structures are inclined relative to a third direction perpendicular to a major surface of the substrate toward a central plane that extends along a second direction perpendicular to the first direction and parallel to the third direction and bisects the stacked structure.

4. The three-dimensional semiconductor device of claim 3, wherein the first and second channel structures form an angle with the third direction that is greater than an angle formed by the first and second dummy channel structures with the third direction.

5. The three-dimensional semiconductor device of claim 3, wherein the first and second dummy channel structures are parallel to the third direction.

6. The three-dimensional semiconductor device of claim 1, wherein the common source line between the first and second channel structures is inclined relative to a third direction perpendicular to a major surface of the substrate toward a central plane extending along a second direction perpendicular to the first direction and parallel to the third direction and bisecting the stacked structure.

7. The three-dimensional semiconductor device of claim 6, wherein the common source line between the first and second channel structures forms an angle with the third direction that is greater than an angle formed by the common source line between the first and second dummy channel structures with the third direction.

8. The three-dimensional semiconductor device of claim 7, wherein the common source line between the first dummy channel structure and the second dummy channel structure is parallel to the third direction.

9. The three-dimensional semiconductor device of claim 1, wherein the common source line traverses the pad region and the cell region.

10. The three-dimensional semiconductor device of claim 1, further comprising:

a third dummy channel structure disposed farther from the cell area than the first and second dummy channel structures; and

a fourth dummy channel structure spaced apart from the third dummy channel structure in the first direction,

wherein the common source line passes between the third dummy channel structure and the fourth dummy channel structure, an

A difference between a distance between the common source line and the third dummy channel structure in the first direction and a distance between the common source line and the fourth dummy channel structure in the first direction is greater than a difference between a distance between the common source line and the first dummy channel structure in the first direction and a distance between the common source line and the second dummy channel structure in the first direction.

11. A three-dimensional semiconductor device comprising:

a stacked structure disposed on a substrate and including a first pad region, a second pad region spaced apart from the first pad region in a first direction, and a unit region interposed between the first pad region and the second pad region; and

a first common source line crossing the first pad region, the cell region and the second pad region,

wherein the first common source line in the first and second pad regions is parallel to a vertical direction perpendicular to a main surface of the substrate, the first common source line in the cell region being inclined with respect to the vertical direction.

12. The three-dimensional semiconductor device of claim 11, further comprising a second common source line crossing the first pad region,

wherein the second common source line is parallel to the vertical direction.

13. The three-dimensional semiconductor device of claim 11, further comprising a third common source line crossing the second pad region,

wherein the third common source line is parallel to the vertical direction.

14. The three-dimensional semiconductor device of claim 11, wherein the first common source line in the cell region is tilted with respect to the vertical direction toward a central plane that extends along the first direction and is parallel to the vertical direction and bisects the stacked structure.

15. The three-dimensional semiconductor device of claim 11, wherein a distance between a central plane and the first common source line varies depending on a position in the first direction, the central plane extending along the first direction and parallel to the vertical direction and bisecting the stacked structure.

16. The three-dimensional semiconductor device according to claim 15, wherein a distance between the first common source line and the central plane in the first pad region and the second pad region increases as a position in the first direction becomes farther from the cell region.

17. The three-dimensional semiconductor device according to claim 15, wherein a distance between the first common source line and the central plane in the first pad region and the second pad region increases and then decreases as a position in the first direction becomes farther from the cell region.

18. The three-dimensional semiconductor device of claim 15, wherein

The first common source line includes a first portion crossing the cell region, a second portion crossing the first pad region, and a third portion crossing the second pad region,

each of the first portion, the second portion, and the third portion of the first common source line is parallel to the first direction, an

The first portion is closer to the central plane than the second portion and the third portion.

19. The three-dimensional semiconductor device of claim 15, wherein

The first common source line comprises a plurality of portions,

each of the plurality of portions is parallel to the first direction, an

Distances from the central plane to the plurality of portions are different.

20. The three-dimensional semiconductor device of claim 11, wherein at least a portion of a cross section of the first common source line is curved, the cross section being perpendicular to the vertical direction.

21. A three-dimensional semiconductor device comprising:

a substrate;

a stacked structure disposed on the substrate, the stacked structure including a first pad region, a second pad region spaced apart from the first pad region in a first direction, and a cell region interposed between the first pad region and the second pad region;

first and second dummy channel structures both located on one side of a central plane perpendicular to a major surface of the substrate, extending in the first direction and bisecting the stacked structure and penetrating the first pad region;

a third dummy channel structure and a fourth dummy channel structure both located on another side of the central plane and penetrating the first pad area;

a first common source line passing between the first dummy channel structure and the second dummy channel structure; and

a second common source line passing between the third dummy channel structure and the fourth dummy channel structure,

wherein the first common source line is closer to one of the first and second dummy channel structures that is farther from the central plane, an

The second common source line is closer to one of the third and fourth dummy channel structures that is farther from the center plane.

22. The three-dimensional semiconductor device of claim 21, wherein a distance between the central plane and the first common source line at a location between the first dummy channel structure and the second dummy channel structure is different than a distance between the central plane and the second common source line at a location between the third dummy channel structure and the fourth dummy channel structure.

23. The three-dimensional semiconductor device of claim 21, wherein the first common source line is mirror symmetric to the second common source line.

24. The three-dimensional semiconductor device of claim 21, wherein

The first common source line passes between a first word line contact and a second word line contact,

the second common source line passes between a third word line contact and a fourth word line contact,

the first common source line is closer to one of the first and second word line contacts that is farther from the central plane, an

The second common source line is closer to one of the third and fourth word line contacts that is farther from the central plane.

25. The three-dimensional semiconductor device of claim 24, wherein a distance between the central plane and the first common source line at a location between the first and second word line contacts is different than a distance between the central plane and the second common source line at a location between the third and fourth word line contacts.

Technical Field

The present inventive concept relates to a three-dimensional semiconductor device, and more particularly, to a three-dimensional nonvolatile semiconductor memory device.

Background

The continuous trend toward miniaturization to produce light, thin and small electronic products having a large capacity has led to an increase in demand for highly integrated semiconductor memory devices. To meet such a demand, three-dimensional semiconductor memory devices have been developed. The three-dimensional semiconductor memory device includes a layer stacked on a substrate and a channel structure penetrating the stacked layer. The number of memory cells per unit area of the substrate can be increased by increasing the number of layers stacked on the substrate. However, due to the increase in the number of layers of the stack, internal stress may occur in the stack structure during the manufacturing process, resulting in the formation of various defects, which may thus reduce the reliability of the three-dimensional semiconductor memory device.

Disclosure of Invention

The inventive concept provides a three-dimensional semiconductor device that prevents a bridge from occurring between a common source line and a word line contact, and a method of manufacturing the same.

According to an aspect of the inventive concept, there is provided a three-dimensional semiconductor device including: a substrate; a stack structure disposed on the substrate, the stack structure including a cell region and a pad region; a first channel structure penetrating the cell region; a second channel structure penetrating the cell region and spaced apart from the first channel structure in the first direction; a first dummy channel structure penetrating the pad region; a second dummy channel structure penetrating the pad region and spaced apart from the first dummy channel structure in the first direction; and a common source line passing between the first channel structure and the second channel structure and between the first dummy channel structure and the second dummy channel structure, wherein a distance between the common source line and the first channel structure in the first direction is equal to a distance between the common source line and the second channel structure in the first direction, and the distance between the common source line and the first dummy channel structure in the first direction is different from the distance between the common source line and the second dummy channel structure in the first direction.

According to another aspect of the inventive concept, there is provided a three-dimensional semiconductor device including: a stacked structure disposed on a substrate and including a first pad region, a second pad region spaced apart from the first pad region in a first direction, and a unit region interposed between the first pad region and the second pad region; and a first common source line crossing the first pad region, the cell region and the second pad region, wherein the first common source line in the first pad region and the second pad region is parallel to a vertical direction perpendicular to a main surface of the substrate, and the first common source line in the cell region is inclined with respect to the vertical direction.

According to another aspect of the inventive concept, there is provided a three-dimensional semiconductor device including: a substrate; a stacked structure disposed on the substrate, the stacked structure including a first pad region, a second pad region spaced apart from the first pad region in a first direction, and a cell region interposed between the first pad region and the second pad region; first and second dummy channel structures both located on one side of a central plane and penetrating the first pad area, the central plane perpendicular to the major surface of the substrate, extending in a first direction and bisecting the stacked structure; third and fourth dummy channel structures both located on another side of the central plane and penetrating the first pad region; a first common source line passing between the first dummy channel structure and the second dummy channel structure; and a second common source line passing between the third dummy channel structure and the fourth dummy channel structure, wherein the first common source line is closer to one of the first dummy channel structure and the second dummy channel structure that is farther from the central plane, and the second common source line is closer to one of the third dummy channel structure and the fourth dummy channel structure that is farther from the central plane.

According to another aspect of the inventive concept, there is provided a method of fabricating a three-dimensional semiconductor device, the method including: forming a stacked structure in which a plurality of insulating layers and a plurality of sacrificial layers are alternately stacked on a substrate; forming first and second channel structures penetrating a cell area of the stacked structure and spaced apart from each other in a horizontal direction parallel to a major surface of the substrate, and first and second dummy channel structures penetrating a pad area of the stacked structure and spaced apart from each other in the horizontal direction; forming word line cuts between the first channel structure and the second channel structure and between the first dummy channel structure and the second dummy channel structure; removing the plurality of sacrificial layers; filling the space from which the plurality of sacrificial layers are removed with a plurality of conductive layers; and forming a common source line to fill the word line cut, wherein a distance between the word line cut and the first channel structure in the horizontal direction is equal to a distance between the word line cut and the second channel structure in the horizontal direction, the distance between the word line cut and the first dummy channel structure in the horizontal direction being different from the distance between the word line cut and the second dummy channel structure in the horizontal direction.

Drawings

Exemplary embodiments of the inventive concept will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

fig. 1 is a top view of a three-dimensional semiconductor device according to an exemplary embodiment of the inventive concept;

fig. 2A to 2D are enlarged views of a first common source line each according to an exemplary embodiment of the inventive concept;

fig. 3A to 3D are enlarged views of a second common source line and a third common source line each according to an exemplary embodiment of the inventive concept;

fig. 4A to 4D are enlarged views of fig. 1;

FIG. 5 is a cross-sectional view taken along line AA' of FIG. 1;

FIG. 6 is a cross-sectional view taken along line BB' of FIG. 1;

FIG. 7 is a cross-sectional view taken along line CC' of FIG. 1;

fig. 8 is an enlarged view of a region R in fig. 5 according to an exemplary embodiment of the inventive concept;

fig. 9 is an enlarged view of a region R in fig. 5 according to an exemplary embodiment of the inventive concept;

fig. 10A is a top view illustrating a method of manufacturing a semiconductor device according to an exemplary embodiment of the inventive concept;

fig. 10B to 14B are cross-sectional views illustrating a method of manufacturing a semiconductor device according to an exemplary embodiment of the inventive concept;

fig. 15A to 15C are plan views showing the arrangement of word line cutouts; and

fig. 16 shows an example of comparing the shape of the first word line cut before the first common source line is formed with the shape of the first common source line after the first common source line filling the first word line cut is formed.

Because the diagrams in fig. 1-16 are intended for illustrative purposes, the elements in the diagrams are not necessarily drawn to scale. For example, some elements may be exaggerated or exaggerated for clarity.

Detailed Description

Fig. 1 is a top view of a three-dimensional semiconductor device according to an exemplary embodiment of the inventive concept.

Referring to fig. 1, the stacked structure SS may include a first PAD area PAD1, a CELL area CELL, and a second PAD area PAD 2. The first and second PAD regions PAD1 and PAD2 may be spaced apart from each other in a first direction X, also referred to as a horizontal direction X, parallel to a main surface of the substrate 110 (see fig. 5 to 7), and the CELL region CELL may be interposed between the first and second PAD regions PAD1 and PAD 2. Hereinafter, the central plane CP refers to a plane extending in the first direction X and parallel to the third direction Z, also referred to as the vertical direction Z, perpendicular to the main surface of the substrate 110 (see fig. 5 to 7), and bisecting the stacked structure SS.

The first common source line CSL1 may cross the first PAD area PAD1, the CELL area CELL, and the second PAD area PAD 2. The second common source line CSL2 may cross the first PAD area PAD 1. The third common source line CSL3 may cross the second PAD area PAD 2.

A plurality of channel structures CH may penetrate the CELL region CELL per one. For example, the plurality of channel structures CH may each penetrate the CELL region CELL of the stacked structure SS by extending in the third direction Z (vertical direction Z), but may not be parallel to the third direction Z. The plurality of dummy channel structures DCH may each penetrate the first PAD area PAD1 or the second PAD area PAD 2. For example, the plurality of dummy channel structures DCH may each penetrate the first PAD area PAD1 or the second PAD area PAD2 of the stack structure SS by extending in the third direction Z (vertical direction Z). A plurality of word line contacts WLC may each be placed on the first PAD area PAD1 or the second PAD area PAD 2. For example, the plurality of word line contacts WLC may each extend in the third direction Z (vertical direction Z), but may not penetrate the first PAD area PAD1 or the second PAD area PAD2 of the stack structure SS. In an exemplary embodiment of the inventive concept, each of the plurality of word line contacts WLC may be surrounded by four dummy channel structures DCH. The arrangement of the plurality of channel structures CH and the plurality of dummy channel structures DCH as shown in fig. 1 is merely an example, and may be variously modified.

The first common source line CSL1 may pass between the dummy channel structures DCH of the first PAD area PAD1, between the channel structures CH of the CELL area CELL, and between the dummy channel structures DCH of the second PAD area PAD 2. The second common source line CSL2 may pass between the dummy channel structures DCH of the first PAD area PAD 1. The third common source line CSL3 may pass between the dummy channel structures DCH of the second PAD area PAD 2. The relative arrangement of the first to third common source lines CSL1, CSL2 and CSL3, the plurality of channel structures CH, and the plurality of dummy channel structures DCH is described in more detail with reference to fig. 4A to 4C.

Fig. 2A to 2D are enlarged views of first common source lines each according to an exemplary embodiment of the inventive concept. Fig. 3A to 3D are enlarged views of a second common source line and a third common source line each according to an exemplary embodiment of the inventive concept.

Referring to fig. 2A, a distance between the first common source line CSL1 and the central plane CP in the second direction Y, also referred to as a horizontal direction Y, parallel to the main surface of the substrate 110 (see fig. 5 to 7) may be constant in the CELL region CELL. A distance between the first common source line CSL1 and the central plane CP in the second direction Y in the first PAD area PAD1 and the second PAD area PAD2 may vary depending on a position in the first direction X. For example, as the position in the first direction X becomes more distant from the CELL region CELL, the distance between the first common source line CSL1 and the central plane CP in the second direction Y may increase in the first and second PAD regions PAD1 and PAD 2. In an exemplary embodiment of the inventive concept, as the position in the first direction X becomes more distant from the CELL region CELL, the distance between the first common source line CSL1 and the central plane CP in the second direction Y may first increase and then converge to a constant value. A cross section of the first common source line CSL1 perpendicular to the third direction Z in the CELL region CELL may be a straight line parallel to the first direction X. At least a portion of a cross-section of the first common source line CSL1 is curved, wherein the cross-section is perpendicular to the third (vertical) direction Z. For example, a cross section of the first common source line CSL1 perpendicular to the third direction Z in the first and second PAD areas PAD1 and PAD area PAD2 may be curved. A distance between the first common source line CSL1 and the center plane CP in the second direction Y in each of the first and second PAD regions PAD1 and PAD region PAD2 may have a maximum value at an end of the first common source line CSL1, the end of the first common source line CSL1 being located at an end of each of the first and second PAD regions PAD1 and PAD region PAD2 distant from the CELL region CELL.

Referring to fig. 3A, the second common source line CSL2 may cross the first PAD area PAD1 in the first direction X, and a distance between the second common source line CSL2 and the central plane CP in the second direction Y may vary depending on a position in the first direction X. For example, as the position in the first direction X becomes more distant from the CELL region CELL, the distance between the second common source line CSL2 and the central plane CP in the second direction Y may increase. In an exemplary embodiment of the inventive concept, as the position in the first direction X becomes more distant from the CELL region CELL, the distance between the second common source line CSL2 and the central plane CP in the second direction Y may increase and then converge to a constant value. The distance between the second common source line CSL2 and the central plane CP in the second direction Y has a maximum at an end of the second common source line CSL2, the end of the second common source line CSL2 being located at an end of the first PAD region PAD1 away from the CELL region CELL. A cross section of the second common source line CSL2 perpendicular to the third direction Z may be curved.

The third common source line CSL3 may cross the second PAD area PAD2 in the first direction X, and a distance between the third common source line CSL3 and the central plane CP in the second direction Y may vary depending on a position in the first direction X. For example, as the position in the first direction X becomes more distant from the CELL region CELL, the distance between the third common source line CSL3 and the center plane CP in the second direction Y may increase. In an exemplary embodiment of the inventive concept, as the position in the first direction X becomes more distant from the CELL region CELL, the distance between the third common source line CSL3 and the central plane CP in the second direction Y may first increase and then converge to a constant value. The distance between the third common source line CSL3 and the center plane CP in the second direction Y may have a maximum at an end of the third common source line CSL3, the end of the third common source line CSL3 being located at an end of the second PAD region PAD2 distant from the CELL region CELL. A cross section of the third common source line CSL3 perpendicular to the third direction Z may be curved.

Referring to fig. 2B, a distance between the first common source line CSL1 and the central plane CP in the second direction Y may be constant in the CELL region CELL. As the position in the first direction X becomes more distant from the CELL region CELL, the distance between the first common source line CSL1 and the central plane CP in the first direction Y may increase and then decrease in the first and second PAD regions PAD1 and PAD 2. The distance between the first common source line CSL1 and the center plane CP in the second direction Y may have a maximum value at any point at the center of each of the first PAD area PAD1 and the second PAD area PAD2 in the first direction X.

Referring to fig. 3B, as the position in the first direction X becomes more distant from the CELL region CELL, the distance between the second common source line CSL2 and the central plane CP in the second direction Y may increase and then decrease. The distance between the second common source line CSL2 and the center plane CP in the second direction Y may have a maximum value at any point at the center of the first PAD area PAD1 in the first direction X.

As the position in the first direction X becomes farther from the CELL region CELL, the distance between the third common source line CSL3 and the center plane CP in the second direction Y may increase and then decrease. The distance between the third common source line CSL3 and the center plane CP in the second direction Y may have a maximum value at any point at the center of the second PAD area PAD2 in the first direction X.

Referring to fig. 2C, the first common source line CSL1 may include a plurality of portions extending in the first direction X. That is, the first common source line CSL1 may include a first portion P1 in the CELL region CELL, a second portion P2 in the first PAD region PAD1, and a third portion P3 in the second PAD region PAD 2. Each portion of the first common source line CSL1 has a constant distance from the central plane CP in the second direction Y. That is, a cross section of each portion of the first common source line CSL1 perpendicular to the third direction Z may be straight, for example, may be a straight line parallel to the first direction X. A distance between the first portion P1 of the first common source line CSL1 and the central plane CP may be smaller than a distance between the second portion P2 of the first common source line CSL1 and the central plane CP. Similarly, a distance between the first portion P1 of the first common source line CSL1 and the central plane CP may be smaller than a distance between the third portion P3 of the first common source line CSL1 and the central plane CP.

Referring to fig. 3C, the second and third common source lines CSL2 and CSL3 may extend in the first direction X. A cross section of the second common source line CSL2 perpendicular to the third direction Z and a cross section of the third common source line CSL3 perpendicular to the third direction Z may be straight, for example, may be straight lines parallel to the first direction X.

Referring to fig. 2D, the first common source line CSL1 may include a first portion P1 in the CELL region CELL, second to fourth portions P2 to P4 sequentially arranged from the first portion P1 in the first PAD region PAD1, and fifth to seventh portions P5 to P7 sequentially arranged from the first portion P1 in the second PAD region PAD 2. However, the inventive concept is not limited thereto. For example, unlike in fig. 2D, the first common source line CSL1 may include five portions or more than seven portions. Each of the first to seventh portions P1 to P7 may extend in the first direction X and may have a constant distance from the central plane CP in the second direction Y. That is, a cross section of each portion of the first common source line CSL1 perpendicular to the third direction Z may be straight, for example, may be a straight line parallel to the first direction X.

In an exemplary embodiment of the inventive concept, a portion farther from the CELL region CELL may be farther from the central plane CP than other portions closer to the CELL region CELL. For example, the second portion P2 may be farther from the central plane CP than the first portion P1, the third portion P3 may be farther from the central plane CP than the second portion P2, the fourth portion P4 may be farther from the central plane CP than the third portion P3, the fifth portion P5 may be farther from the central plane CP than the first portion P1, the sixth portion P6 may be farther from the central plane CP than the fifth portion P5, and the seventh portion P7 may be farther from the central plane CP than the sixth portion P6. However, the inventive concept is not limited thereto. For example, in an exemplary embodiment of the inventive concept, unlike in fig. 2D, in the local region, a portion farther from the CELL region CELL may be closer to the central plane CP. For example, the fourth portion P4 may be closer to the central plane CP than the third portion P3.

Referring to fig. 3D, the second common source line CSL2 may include a plurality of portions, i.e., eighth to tenth portions P8 to P10, sequentially arranged from the boundary of the CELL region CELL in the first PAD region PAD 1. Each of the eighth to tenth portions P8 to P10 may extend in the first direction X and may have a constant distance from the central plane CP in the second direction Y. That is, a cross section of each portion of the second common source line CSL2 perpendicular to the third direction Z may be straight, for example, may be a straight line parallel to the first direction X. Distances between the eighth to tenth sections P8 to P10 and the central plane CP may be different from each other. For example, a portion farther from the CELL region CELL may be farther from the center plane CP. That is, the ninth portion P9 may be farther from the central plane CP than the eighth portion P8, and the tenth portion P10 may be farther from the central plane CP than the ninth portion P9. However, the inventive concept is not limited thereto. For example, in an exemplary embodiment of the inventive concept, unlike in fig. 3D, in the local region, a portion farther from the CELL region CELL may be closer to the central plane CP. For example, the tenth portion P10 may be closer to the central plane CP than the ninth portion P9.

The third common source line CSL3 may include a plurality of portions, i.e., eleventh to thirteenth portions P11 to P13, sequentially arranged from the boundary of the CELL region CELL in the second PAD region PAD 2. Each of the eleventh to thirteenth portions P11 to P13 may extend in the first direction X and may have a constant distance from the central plane CP in the second direction Y. That is, a cross section of each portion of the third common source line CSL3 perpendicular to the third direction Z may be straight, for example, may be a straight line parallel to the first direction X. Distances between the eleventh to thirteenth portions P11 to P13 and the central plane CP may be different from each other. For example, a portion farther from the CELL region CELL may be farther from the center plane CP. That is, the twelfth portion P12 may be farther from the central plane CP than the eleventh portion P11, and the thirteenth portion P13 may be farther from the central plane CP than the twelfth portion P12. However, the inventive concept is not limited thereto. For example, in an exemplary embodiment of the inventive concept, unlike in fig. 3D, in the local region, a portion farther from the CELL region CELL may be closer to the central plane CP. For example, the thirteenth portion P13 may be closer to the central plane CP than the twelfth portion P12.

Fig. 4A to 4D are enlarged views of fig. 1.

Referring to fig. 4A, the first and second channel structures CH1 and CH2 may be spaced apart from each other in the second direction Y. The first dummy channel structure DCH1 and the second dummy channel structure DCH2 may be spaced apart from each other in the second direction Y. The third dummy channel structure DCH3 and the fourth dummy channel structure DCH4 may be spaced apart from each other in the second direction Y. The first channel structure CH1, the first dummy channel structure DCH1, and the third dummy channel structure DCH3 may be aligned with the second channel structure CH2, the second dummy channel structure DCH2, and the fourth dummy channel structure DCH4, respectively, along the second direction Y. In the CELL region CELL, the first common source line CSL1 may pass between the first channel structure CH1 and the second channel structure CH 2. Further, in the first PAD area PAD1, the first common source line CSL1 may pass between the first dummy channel structure DCH1 and the second dummy channel structure DCH2 and between the third dummy channel structure DCH3 and the fourth dummy channel structure DCH 4.

A distance d1 between the first common source line CSL1 and the first channel structure CH1 in the second direction Y may be equal to a distance d2 between the first common source line CSL1 and the second channel structure CH2 in the second direction Y. On the other hand, a distance d3 between the first common source line CSL1 and the first dummy channel structure DCH1 in the second direction Y may be different from a distance d4 between the first common source line CSL1 and the second dummy channel structure DCH2 in the second direction Y. Further, a distance d5 between the first common source line CSL1 and the third dummy channel structure DCH3 in the second direction Y may be different from a distance d6 between the first common source line CSL1 and the fourth dummy channel structure DCH4 in the second direction Y.

In an exemplary embodiment of the inventive concept, a difference between a distance d5 between the first common source line CSL1 and the third dummy channel structure DCH3 in the second direction Y and a distance d6 between the first common source line CSL1 and the fourth dummy channel structure DCH4 in the second direction Y may be greater than a difference between a distance d3 between the first common source line CSL1 and the first dummy channel structure DCH1 in the second direction Y and a distance d4 between the first common source line CSL1 and the second dummy channel structure DCH2 in the second direction Y.

The first common source line CSL1 may be closer to one of the first dummy channel structure DCH1 and the second dummy channel structure DCH2 that is farther from the center plane CP (see fig. 1). For example, because the first dummy channel structure DCH1 is farther from the center plane CP (see fig. 1) than the second dummy channel structure DCH2, the first common source line CSL1 may be closer to the first dummy channel structure DCH 1. Similarly, the first common source line CSL1 may be closer to one of the third dummy channel structure DCH3 and the fourth dummy channel structure DCH4 that is farther from the center plane CP (see fig. 1). For example, because the third dummy channel structure DCH3 is farther from the center plane CP (see fig. 1) than the fourth dummy channel structure DCH4, the first common source line CSL1 may be closer to the third dummy channel structure DCH 3.

The first and second channel structures CH1 and CH2 in the CELL region CELL may be mirror-symmetrical with respect to the first common source line CSL1, but the first and second dummy channel structures DCH1 and DCH2 in the first PAD region PAD1 may not be mirror-symmetrical with respect to the first common source line CSL 1. As such, in the first and second PAD areas PAD1 and PAD2, the first common source line CSL1 may be arranged such that the dummy channel structure DCH is asymmetric with respect to the first common source line CSL 1.

Referring to fig. 4B, the second common source line CSL2 in the first PAD area PAD1 may pass between the fifth dummy channel structure DCH5 and the sixth dummy channel structure DCH 6. The fifth dummy channel structure DCH5 and the sixth dummy channel structure DCH6 may be spaced apart from each other in the second direction Y and may be aligned along the second direction Y. A distance d7 between the second common source line CSL2 and the fifth dummy channel structure DCH5 in the second direction Y may be different from a distance d8 between the second common source line CSL2 and the sixth dummy channel structure DCH6 in the second direction Y. The second common source line CSL2 may be closer to one of the fifth dummy channel structure DCH5 and the sixth dummy channel structure DCH6 that is farther from the center plane CP (see fig. 1). For example, because the fifth dummy channel structure DCH5 is farther from the center plane CP (see fig. 1) than the sixth dummy channel structure DCH6, the second common source line CSL2 may be closer to the fifth dummy channel structure DCH 5. That is, the fifth dummy channel structure CH5 and the sixth dummy channel structure CH6 in the first PAD area PAD1 may not be mirror-symmetrical with respect to the second common source line CSL 2. As such, the second common source line CSL2 in the first PAD area PAD1 may be arranged such that the dummy channel structure DCH is asymmetric with respect to the second common source line CSL 2.

Referring to fig. 4C, the third common source line CSL3 in the second PAD area PAD2 may pass between the seventh dummy channel structure DCH7 and the eighth dummy channel structure DCH 8. The seventh dummy channel structure DCH7 and the eighth dummy channel structure DCH8 may be spaced apart from each other in the second direction Y and may be aligned along the second direction Y. A distance d9 between the third common source line CSL3 and the seventh dummy channel structure DCH7 in the second direction Y may be different from a distance d10 between the third common source line CSL3 and the eighth dummy channel structure DCH8 in the second direction Y. The third common source line CSL3 may be closer to one of the seventh dummy channel structure DCH7 and the eighth dummy channel structure DCH8 that is farther from the center plane CP (see fig. 1). For example, because the seventh dummy channel structure DCH7 is farther from the center plane CP (see fig. 1) than the eighth dummy channel structure DCH8, the third common source line CSL3 may be closer to the seventh dummy channel structure DCH 7. That is, the seventh dummy channel structure CH7 and the eighth dummy channel structure CH8 in the second PAD area PAD2 may not be mirror-symmetrical with respect to the third common source line CSL 3. As such, the third common source line CSL3 in the second PAD area PAD2 may be arranged such that the dummy channel structure DCH is asymmetric with respect to the third common source line CSL 3.

Referring to fig. 4D, the fourth common source line CSL4 may pass between the ninth dummy channel structure DCH9 and the tenth dummy channel structure DCH 10. In an exemplary embodiment of the inventive concept, the fourth common source line CSL4 may be mirror-symmetrical to the first common source line CSL 1. The first, second, ninth, and tenth dummy channel structures DCH1, DCH2, DCH9, and DCH10 may be aligned along the second direction Y, and thus may have positions that are different in the second direction Y and substantially the same in the first direction X. The first common source line CSL1 may be closer to the first dummy channel structure DCH1, with the first dummy channel structure DCH1 being farther from the center plane CP than the second dummy channel structure DCH 2. The fourth common source line CSL4 may be closer to the ninth dummy channel structure DCH9, the ninth dummy channel structure DCH9 being further from the center plane CP than the tenth dummy channel structure DCH 10. In an exemplary embodiment of the inventive concept, a distance d11 between the center plane CP and the first common source line CSL1 at a position between the first dummy channel structure DCH1 and the second dummy channel structure DCH2 may be different from a distance d12 between the center plane CP and the fourth common source line CSL4 at a position between the ninth dummy channel structure DCH9 and the tenth dummy channel structure DCH 10.

The first common source line CSL1 may pass between the first word line contact WLC1 and the second word line contact WLC 2. The fourth common source line CSL4 may pass between the third word line contact WLC3 and the fourth word line contact WLC 4. The first, second, third and fourth word line contacts WLC1, WLC2, WLC3 and WLC4 may be aligned in the second direction Y and thus may have positions that are different in the second direction Y and substantially the same in the first direction X. The first common source line CSL1 may be closer to the first word line contact WLC1, the first word line contact WLC1 being further from the central plane CP than the second word line contact WLC 2. The fourth common source line CSL4 may be closer to the fourth word line contact WLC4, the fourth word line contact WLC4 being further from the central plane CP than the third word line contact WLC 3. In an exemplary embodiment of the inventive concept, a distance d13 between the central plane CP and the first common source line CSL1 at a location between the first word line contact WLC1 and the second word line contact WLC2 may be different from a distance d14 between the central plane CP and the fourth common source line CSL4 at a location between the third word line contact WLC3 and the fourth word line contact WLC 4.

Fig. 5 is a sectional view taken along line AA ' of fig. 1, fig. 6 is a sectional view taken along line B-B ' of fig. 1, and fig. 7 is a sectional view taken along line CC ' of fig. 1.

Referring to fig. 5 to 7, a three-dimensional semiconductor device according to an exemplary embodiment of the inventive concept may include a substrate 110, a stack structure SS, a channel structure CH, a dummy channel structure DCH, a first common source line CSL1, a second common source line CSL2, a third common source line CSL3 (see fig. 1), and a word line contact WLC.

The substrate 110 may include a semiconductor material, such as a group IV semiconductor material, a group III-V semiconductor material, or a group II-VI semiconductor material. The group IV semiconductor material may include, for example, silicon (Si), germanium (Ge), or a combination thereof. The III-V semiconductor material may include, for example, gallium arsenide (GaAs), indium phosphide (InP), gallium phosphide (GaP), indium arsenide (InAs), indium antimonide (InSb), indium gallium arsenide (InGaAs), or combinations thereof. The II-VI semiconductor material can include, for example, zinc telluride (ZnTe), cadmium sulfide (CdS), or combinations thereof. Substrate 110 may be a bulk wafer or an epitaxial layer.

The stacked structure SS may be located on the substrate 110. The first PAD area PAD1 and the second PAD area PAD2 (see fig. 1) of the stacked structure SS may be stepped. For example, steps in the first PAD area PAD1 and the second PAD area PAD2 (see fig. 1) of the stacked structure SS may have steps fromThe area of the lowest level thereof decreasing at a given rate toward the uppermost level thereof. The stacked structure SS may include a plurality of insulating layers 120 and a plurality of conductive layers 130. The plurality of insulating layers 120 may include, for example, silicon oxide (SiO)₂). The plurality of conductive layers 130 may include, for example, copper (Cu), aluminum (Al), silver (Ag), gold (Au), tungsten (W), or a combination thereof. The plurality of insulating layers 120 and the plurality of conductive layers 130 may be alternately stacked one on another. Each of the plurality of conductive layers 130 may function as one of a ground selection line, a word line, and a string selection line of the nonvolatile semiconductor memory device. For example, the conductive layer 130 closest to the substrate 110 may be a ground select line, the conductive layer 130 farthest from the substrate 110 may be a string select line, and the remaining conductive layers 130 may be word lines. However, the inventive concept is not limited thereto. For example, two conductive layers 130 may function as a string selection line, and may be formed at the uppermost level and one level immediately below the uppermost level.

The channel structure CH may contact the major surface of the substrate 110 through the CELL region CELL. The detailed structure of the channel structure CH is described in more detail below with reference to fig. 8 and 9. Due to internal stresses, the channel structure CH may be inclined in the CELL region CELL towards the central plane CP with respect to the third direction Z. The channel structure CH may form an angle with the third direction Z greater than an angle formed by the dummy channel structure DCH with the third direction Z. The internal stress may be offset in the first PAD area PAD1 and the second PAD area PAD2 (see fig. 1). For example, the dummy channel structure DCH may be parallel to the third direction Z. The dummy channel structure DCH may contact the main surface of the substrate 110 through the first PAD area PAD1 or the second PAD area PAD2 (see fig. 1). The detailed structure of the dummy channel structure DCH may be similar to that of the channel structure CH which will be described with reference to fig. 8 and 9.

The first common source line CSL1 may contact the main surface of the substrate 110 through the CELL region CELL, the first PAD region PAD1, and the second PAD region PAD2 (see fig. 1). The second common source line CSL2 may contact the main surface of the substrate 110 through the first PAD area PAD 1. The third common source line CSL3 (see fig. 1) may contact the main surface of the substrate 110 through the second PAD area PAD 2.

Insulating layers may be located between the first common source line CSL1 and the stack structure SS, between the second common source line CSL2 and the stack structure SS, and between the third common source line CSL3 and the stack structure SS.

The first, second, and third common source lines CSL1, CSL2, and CSL3 may include, for example, Cu, Al, Ag, Au, W, or a combination thereof.

Due to internal stresses, the first common source line CSL1 may be inclined toward the center plane CP with respect to the third direction Z in the CELL region CELL. As shown in fig. 5, the first common source line CSL1 between the channel structures CH may be inclined with respect to the third direction Z toward the central plane CP. An angle formed by the first common source line CSL1 and the third direction Z in the CELL region CELL may be greater than an angle formed by the first common source line CSL1 and the third direction Z in the first and second PAD regions PAD1 and PAD 2. In an exemplary embodiment of the inventive concept, an angle formed by the first common source line CSL1 and the third direction Z in the first and second PAD regions PAD1 and PAD region PAD2 (see fig. 1) may increase as the position of the first common source line CSL1 becomes closer to the CELL region CELL. The internal stress may be offset in the first PAD area PAD1 and the second PAD area PAD2 (see fig. 1). In an exemplary embodiment of the inventive concept, the first common source line CSL1 may be parallel to the third direction Z in the first and second PAD areas PAD1 and PAD area PAD2 (see fig. 1). As shown in fig. 6, the first common source line CSL1 between the dummy channel structures DCH may be parallel to the third direction Z. In addition, the second common source line CSL2 may be parallel to the third direction Z in the first PAD area PAD 1. Further, the third common source line CSL3 (see fig. 1) may be parallel to the third direction Z in the second PAD area PAD2 (see fig. 1).

Referring to fig. 1 and 7, the plurality of word line contacts WLC may be placed on the first PAD area PAD1 or the second PAD area PAD 2. Since the first common source line CSL1 is parallel to the third direction Z in the first and second PAD regions PAD1 and PAD2, the second common source line CSL2 is parallel to the third direction Z in the first PAD region PAD1, the third common source line CSL3 is parallel to the third direction Z in the second PAD region PAD2, and the word line contacts WLC are parallel to the third direction Z in the first and second PAD regions PAD1 and PAD2, the plurality of word line contacts WLC may not contact the first common source line CSL1, the second common source line CSL2, or the third common source line CSL 3.

According to an exemplary embodiment of the inventive concept, the asymmetric arrangement of the first to third common source lines CSL1, CSL2, and CSL3 in the first PAD area PAD1 and the second PAD area PAD2 causes an internal stress that causes the dummy channel structure DCH and the first to third common source lines CSL1, CSL2, and CSL3 to be inclined away from the center plane CP with respect to the third direction Z. The internal stresses due to the asymmetric arrangement of the first to third common source lines CSL1, CSL2, and CSL3 may counteract the internal stresses that cause the first to third common source lines CSL1, CSL2, and CSL3 to tilt toward the central plane CP relative to the third direction Z. Accordingly, the first to third common source lines CSL1, CSL2 and CSL3, and the dummy channel structure DCH are prevented from being inclined toward the central plane CP with respect to the third direction Z in the first PAD area PAD1 and the second PAD area PAD 2. Accordingly, it may be possible to prevent a bridge from being formed between the first to third common source lines CSL1, CSL2, and CSL3 and the plurality of word line contacts WLC. For example, when the first to third common source lines CSL1, CSL2, and CSL3 are inclined, bridges may be formed between the first to third common source lines CSL1, CSL2, and CSL3 and the plurality of word line contacts WLC. For example, an upper portion of one of the inclined first to third common source lines CSL1, CSL2, and CSL3 may contact an adjacent word line contact WLC to form a bridge.

Fig. 8 is an enlarged view of a region R in fig. 5 according to an exemplary embodiment of the inventive concept.

Referring to fig. 8, a channel structure CH (see fig. 5) may include a channel layer 150, a buried insulating layer 160, and an information storage layer 140. The channel layer 150 may include a semiconductor material such as, for example, silicon (Si), germanium (Ge), or a combination thereof. The buried insulating layer 160 may be filled in a space surrounded by the channel layer 150. The buried insulating layer 160 may include, for example, silicon oxide (SiO)₂) Of (4) an insulating material.

The information storage layer 140 may be positioned between the channel layer 150 and the conductive layer 130. The information storage layer 140 may extend between the insulating layer 120 and the channel layer 150 and between the conductive layer 130 and the channel layer 150. The information storage layer 140 may include a blocking insulating layer 141, a charge storage layer 142, and a tunnel insulating layer 143. The blocking insulating layer 141 may be in contact with the conductive layer 130. The tunnel insulating layer 143 may contact the channel layer 150. The charge storage layer 142 may be positioned between the blocking insulating layer 141 and the tunnel insulating layer 143. The blocking insulating layer 141 may include a high dielectric constant material such as, for example, aluminum oxide (Al)₂O₃) Or hafnium oxide (HfO)₂). The charge storage layer 142 may be a trap type. For example, charge storage layer 142 may include quantum dots or nanocrystals. The quantum dots or nanocrystals may comprise fine particles of a conductive material. The charge storage layer 142 may include, for example, silicon nitride (Si)₃N₄). The tunnel insulating layer 143 may include, for example, silicon oxide (SiO)₂)。

Fig. 9 is an enlarged view of a region R in fig. 5 according to an exemplary embodiment of the inventive concept.

As shown in fig. 9, the arrangement and shape of the information storage layer 140 may be modified. In an exemplary embodiment of the inventive concept, the information storage layer 140 may extend between the insulating layer 120 and the conductive layer 130 without extending between the channel layer 150 and the insulating layer 120. In an exemplary embodiment of the inventive concept, as shown in fig. 9, some of the blocking insulating layer 141, the charge storage layer 142, and the tunnel insulating layer 143 constituting the information storage layer 140 may extend between the channel layer 150 and the conductive layer 130, and the remaining portion may extend between the insulating layer 120 and the conductive layer 130.

Fig. 10A is a top view illustrating a method of manufacturing a semiconductor device according to an exemplary embodiment of the inventive concept, and fig. 10B to 14B are cross-sectional views illustrating a method of manufacturing a semiconductor device according to an exemplary embodiment of the inventive concept. Fig. 15A to 15C are plan views showing the arrangement of word line cutouts.

Referring to fig. 10A to 10C, an initial stacked structure SS' may be formed on the substrate 110. The initial stacked structure SS' may include a plurality of insulating layers 120 and a plurality of insulating layers 120 alternately stacked one on anotherAnd a sacrificial layer 190. The plurality of sacrificial layers 190 may include, for example, silicon nitride (Si)₃N₄). The initial stack structure SS' may include a CELL region CELL, a first PAD region PAD1, and a second PAD region PAD 2. The first PAD area PAD1 and the second PAD area PAD2 may be patterned in a step shape. For example, the steps having the patterned step shape in the first PAD area PAD1 and the second PAD area PAD2 of the initial stacked structure SS' may have an area that decreases at a given ratio from the lowermost level thereof toward the uppermost level thereof.

Referring to fig. 11A and 11B, a channel structure CH penetrating the CELL region CELL of the initial stack structure SS' may be formed. Meanwhile, a dummy channel structure DCH penetrating the first PAD area PAD1 or the second PAD area PAD2 (see fig. 10A) of the initial stack structure SS' may be formed. After the channel structure CH and the dummy channel structure DCH are formed, the channel structure CH and the dummy channel structure DCH may be inclined with respect to the third direction Z due to internal stress.

Referring to fig. 12A and 12B, a plurality of word line cuts C may be formed. A portion of the plurality of word line cuts C may cross the first PAD area PAD1, the CELL area CELL, and the second PAD area PAD2 (see fig. 10A), another portion may cross only the first PAD area PAD1, and still another portion may cross only the second PAD area PAD2 (see fig. 10A). The plurality of word line cutouts C may be parallel to the third direction Z. After forming the plurality of word line cuts C, the channel structures CH and the dummy channel structures DCH may be parallel to the third direction Z.

Referring to fig. 15A, the first word line cut C1 may cross the first PAD area PAD1, the CELL area CELL, and the second PAD area PAD2 (see fig. 10A). In the CELL region CELL, the first word line cut C1 may pass between the first channel structure CH1 and the second channel structure CH 2. The first word line cut C1 in the CELL region CELL may be a straight line parallel to the first direction X. Further, in the first PAD area PAD1, the first word line cut C1 may pass between the first dummy channel structure DCH1 and the second dummy channel structure DCH2 and between the third dummy channel structure DCH3 and the fourth dummy channel structure DCH 4. The first word line cut C1 in the first PAD region PAD1 or the second PAD region PAD2 (see fig. 10A) may be straight or may be curved.

The distance d1C between the first word line cut C1 and the first channel structure CH1 in the second direction Y may be equal to the distance d2C between the first word line cut C1 and the second channel structure CH2 in the second direction Y. On the other hand, the distance d3C in the second direction Y between the first word line notch C1 and the first dummy channel structure DCH1 may be different from the distance d4C in the second direction Y between the first word line notch C1 and the second dummy channel structure DCH 2. Further, the distance d5C in the second direction Y between the first word line notch C1 and the third dummy channel structure DCH3 may be different from the distance d6C in the second direction Y between the first word line notch C1 and the fourth dummy channel structure DCH 4.

In an exemplary embodiment of the inventive concept, a difference between a distance d5C between the first word line cut C1 and the third dummy channel structure DCH3 in the second direction Y and a distance d6C between the first word line cut C1 and the fourth dummy channel structure DCH4 in the second direction Y may be greater than a difference between a distance d3C between the first word line cut C1 and the first dummy channel structure DCH1 in the second direction Y and a distance d4C between the first word line cut C1 and the second dummy channel structure DCH2 in the second direction Y.

The first word line cut C1 may be closer to one of the first dummy channel structure DCH1 and the second dummy channel structure DCH2 that is farther from the center plane CP '(see fig. 10A) of the initial stacked structure SS'. For example, because the first dummy channel structure DCH1 is farther from the center plane CP '(see fig. 10A) of the initial stack structure SS' than the second dummy channel structure DCH2, the first word line cut C1 may be closer to the first dummy channel structure DCH 1. Similarly, the first word line cut C1 may be closer to one of the third dummy channel structure DCH3 and the fourth dummy channel structure DCH4 that is farther from the center plane CP '(see fig. 10A) of the initial stack structure SS'. For example, because the third dummy channel structure DCH3 is farther from the center plane CP '(see fig. 10A) of the initial stack structure SS' than the fourth dummy channel structure DCH4, the first word line cut C1 may be closer to the third dummy channel structure DCH 3.

The first and second channel structures CH1 and CH2 in the CELL region CELL may be mirror-symmetrical with respect to the first word line cut C1, but the first and second dummy channel structures DCH1 and DCH2 in the first PAD region PAD1 may not be mirror-symmetrical with respect to the first word line cut C1. As such, in the first and second PAD areas PAD1 and PAD2 (see fig. 10A), the first word line cut C1 may be arranged such that the dummy channel structure DCH is asymmetric with respect to the first word line cut C1.

Referring to fig. 15B, the second word line cut C2 may cross the first PAD area PAD 1. The second word line cut C2 may pass between the fifth dummy channel structure DCH5 and the sixth dummy channel structure DCH 6. The distance d7C in the second direction Y between the second word line cut C2 and the fifth dummy channel structure DCH5 may be different from the distance d8C in the second direction Y between the second word line cut C2 and the sixth dummy channel structure DCH 6. The second word line cut C2 may be closer to one of the fifth dummy channel structure DCH5 and the sixth dummy channel structure DCH6 that is farther from the center plane CP '(see fig. 10A) of the initial stacked structure SS'. For example, because the fifth dummy channel structure DCH5 is farther from the center plane CP '(see fig. 10A) of the initial stack structure SS' than the sixth dummy channel structure DCH6, the second word line cut C2 may be closer to the fifth dummy channel structure DCH 5. That is, the fifth dummy channel structure CH5 and the sixth dummy channel structure CH6 in the first PAD area PAD1 may not be mirror-symmetrical with respect to the second word line cut C2. As such, the second word line cut C2 in the first PAD area PAD1 may be arranged such that the dummy channel structure DCH is asymmetric about the second word line cut C2.

Referring to fig. 15C, the third word line cut C3 may cross the second PAD region PAD 2. The third word line cut C3 may pass between the seventh dummy channel structure DCH7 and the eighth dummy channel structure DCH 8. The distance d9C in the second direction Y between the third word line notch C3 and the seventh dummy channel structure DCH7 may be different from the distance d10C in the second direction Y between the third word line notch C3 and the eighth dummy channel structure DCH 8. The third word line cut C3 may be closer to one of the seventh dummy channel structure DCH7 and the eighth dummy channel structure DCH8 that is farther from the center plane CP '(see fig. 10A) of the initial stacked structure SS'. For example, because the seventh dummy channel structure DCH7 is farther from the center plane CP '(see fig. 10A) of the initial stack structure SS' than the eighth dummy channel structure DCH8, the third word line cut C3 may be closer to the seventh dummy channel structure DCH 7. That is, the seventh dummy channel structure DCH7 and the eighth dummy channel structure DCH8 in the second PAD area PAD2 may not be mirror-symmetrical with respect to the third word line cut C3. As such, the third word line cut C3 in the second PAD area PAD2 may be arranged such that the dummy channel structure DCH is asymmetric about the third word line cut C3.

Referring to fig. 13A and 13B, the sacrificial layer 190 (see fig. 12A and 12B) may be removed.

Referring to fig. 14A and 14B, the conductive layer 130 may be formed in a space from which the sacrificial layer 190 is removed. Accordingly, the stacked structure SS may be formed.

Referring to fig. 1, 5 and 6, first to third common source lines CSL1 to CSL3 may be formed in the plurality of word line cuts C. After the first to third common source lines CSL1 to CSL3 are formed, the first common source line CSL1 may be inclined toward the central plane CP (see fig. 1) with respect to the third direction Z in the CELL region CELL due to internal stress. Further, the channel structure CH in the CELL region CELL may be inclined toward the center plane CP (see fig. 1) with respect to the third direction Z. On the other hand, the internal stress may be offset due to the asymmetric arrangement of the first common source line CSL1 in the first PAD area PAD1 and the second PAD area PAD2, the asymmetric arrangement of the second common source line CSL2 in the first PAD area PAD1, and the asymmetric arrangement of the third common source line CSL3 in the second PAD area PAD 2. Accordingly, the first common source line CSL1 in the first and second PAD areas PAD1 and PAD area PAD2 may be parallel to the third direction Z. The second common source line CSL2 in the first PAD area PAD1 may be parallel to the third direction Z. The third common source line CSL3 in the second PAD area PAD2 may be parallel to the third direction Z. Further, the dummy channel structure DCH may be parallel to the third direction Z.

Next, a plurality of word line contacts WLC may be formed on the first PAD area PAD1 and the second PAD area PAD 2. Since the first to third common source lines CSL1 to CSL3 are parallel to the third direction Z in the first and second PAD regions PAD1 and PAD2, a bridge may be prevented from being formed between the plurality of word line contacts WLC and the first to third common source lines CSL1 to CSL 3. For example, when the first to third common source lines CSL1 to CSL3 are inclined, a bridge may be formed between the first to third common source lines CSL1 to CSL3 and the plurality of word line contacts WLC. For example, an upper portion of one of the inclined first to third common source lines CSL1 to CSL3 may contact an adjacent word line contact WLC to form a bridge. On the other hand, when the word line contacts WLC and the first to third common source lines CSL1 to CSL3 are parallel to the third direction Z, the upper portions of the first to third common source lines CSL1 to CSL3 do not contact the adjacent word line contacts WLC to form a bridge. Accordingly, the asymmetric arrangement of the first to third common source lines CSL1 to CSL3 in the first and second PAD regions PAD1 and PAD region PAD2 according to an exemplary embodiment of the inventive concept may prevent the plurality of word line contacts WLC and the first to third common source lines CSL1 to CSL3 from forming a bridge therebetween, and thus may improve reliability of the three-dimensional semiconductor memory device.

Fig. 16 shows an example of comparing the shape of the first word line cut C1 before the first common source line CSL1 is formed with the shape of the first common source line CSL1 after the first common source line CSL1 filling the first word line cut C1 is formed.

Referring to fig. 16, a portion of the first common source line CSL1 crossing the CELL region CELL after the first common source line CSL1 is formed is inclined toward the central plane CP with respect to the third direction Z due to internal stress, and thus, a difference may occur between the shape of the first word line cut C1 before the first common source line CSL1 is formed and the shape of the first common source line CSL1 after the first common source line CSL1 is formed.

A distance DC in the second direction Y between the portion of the first common source line CSL1 crossing the CELL region CELL and the central plane CP after the first common source line CSL1 is formed may be less than a distance DW in the second direction Y between the portion of the first word line cut C1 crossing the CELL region CELL and the central plane CP before the first common source line CSL1 is formed.

Comparing fig. 4A with fig. 15A, although the shapes of the first common source line CSL1 and the first word line cut C1 are shown as being the same in the drawing, the shape of the first common source line CSL1 may be different from the shape of the first word line cut C1. This is due to deformation of the first and second channel structures CH1 and CH2 and the portion of the first common source line CSL1 crossing the CELL region CELL, which is caused by internal stress occurring after the first to third common source lines CSL1, CSL2, and CSL3 are formed. Accordingly, in an exemplary embodiment of the inventive concept, a distance d1 between the first common source line CSL1 and the first channel structure CH1 and a distance d2 (see fig. 4A) between the first common source line CSL1 and the second channel structure CH2 may be different from a distance d1C between the first word line cut C1 and the first channel structure CH1 and a distance d2C (see fig. 15A) between the first word line cut C1 and the second channel structure CH2, respectively.

While the present inventive concept has been particularly shown and described with reference to specific exemplary embodiments thereof, it will be understood that various changes in form and details may be made therein without departing from the spirit and scope of the inventive concept as defined by the appended claims.

This application claims the benefit of korean patent application No. 10-2018-0108513 filed on the korean intellectual property office on 11/9/2018, the disclosure of which is incorporated herein by reference in its entirety.