Three-dimensional semiconductor memory devices having source structure overlaps buried insulating layer

1. A three-dimensional (3D) semiconductor memory device, comprising:

first and second semiconductor layers horizontally spaced apart from each other;

a buried insulating layer between the first and second semiconductor layers;

a first cell array structure disposed on the first semiconductor layer, and a second cell array structure disposed on the second semiconductor layer; and

an isolation structure disposed on the buried insulating layer between the first and second cell array structures,

wherein the first cell array structure comprises:

an electrode structure including electrodes, which are stacked in a direction perpendicular to a top surface of the first semiconductor layer; and

a first source structure disposed between the first semiconductor layer and the electrode structure,

the first source structure is extended onto the buried insulating layer, and

the isolation structure is between the first source structure of the first cell array structure and a second source structure of the second cell array structure.

2. The 3D semiconductor memory device of claim 1 , wherein the first and second source structures of the first and second cell array structures are electrically separated from each other by the isolation structure.

3. The 3D semiconductor memory device of claim 1 , wherein the first source structure of the first cell array structure is in contact with a side surface of the isolation structure.

4. The 3D semiconductor memory device of claim 1 , wherein a bottom surface of the isolation structure is in contact with the buried insulating layer.

5. The 3D semiconductor memory device of claim 1 , wherein the first cell array structure comprises an electrode isolation structure penetrating the electrode structure and the first source structure,

the electrode isolation structure has a line shape extending in a direction parallel to the top surface of the first semiconductor layer, and

the isolation structure comprises a same material as the electrode isolation structure.

6. The 3D semiconductor memory device of claim 5 , wherein a top surface of the isolation structure is at a same height as a top surface of the electrode isolation structure.

7. The 3D semiconductor memory device of claim 5 , wherein the first cell array structure comprises vertical structures penetrating the electrode structure and the first source structure, and

each of the vertical structures is extended into the first semiconductor layer.

8. The 3D semiconductor memory device of claim 7 , wherein the vertical structures are connected to the first source structure.

9. The 3D semiconductor memory device of claim 7 , Wherein the first cell array structure comprises bit lines, which are disposed on the electrode structure and are connected to the vertical structures, and

a top surface of the isolation structure is higher than top surfaces of the vertical structures and lower than bottom surfaces of the bit lines.

10. The 3D semiconductor memory device of claim 1 , wherein the first cell array structure comprises:

vertical structures penetrating the electrode structure and the first source structure; and

bit lines disposed on the electrode structure and connected to the vertical structures;

wherein a top surface of the isolation structure is higher than top surfaces of the vertical structures and lower than bottom surfaces of the bit lines.

11. The 3D semiconductor memory device of claim 1 , further comprising a peripheral circuit structure on a substrate,

wherein the peripheral circuit structure comprises peripheral circuits, which are disposed on the substrate, and a lower insulating layer, which covers the peripheral circuits, and

the first and second semiconductor layers and the buried insulating layer are disposed on the lower insulating layer.

12. The 3D semiconductor memory device of claim 1 , wherein the isolation structure comprises a conductive pattern and an insulating spacer between the first and second source structures and the conductive pattern.

13. The 3D semiconductor memory device of claim 1 , further comprising an insulating layer disposed on the buried insulating layer and filling a region between the first and second cell array structures,

wherein the isolation structure is extended in the direction perpendicular to the top surface of the first semiconductor layer, and penetrates at least a portion of the insulating layer.

14. A three-dimensional (3D) semiconductor memory device, comprising:

first and second semiconductor layers horizontally spaced apart from each other, on a substrate;

first and second cell array structures disposed on the first and second semiconductor layers, respectively; and

an isolation structure disposed on the substrate between the first and second cell array structures,

wherein the first cell array structure comprises:

an electrode structure including electrodes, which are stacked in a direction perpendicular to a top surface of the first semiconductor layer; and

a first source structure disposed between the first semiconductor layer and the electrode structure, and

the first source structure of the first cell array structure is horizontally extended onto an area of the substrate between the first and second semiconductor layers, and the first source structure of the first cell array structure and a second source structure of the second cell array structure are electrically separated from each other by the isolation structure.

15. The 3D semiconductor memory device of claim 14 , further comprising:

a third semiconductor layer on the substrate; and

a third cell array structure disposed on the third semiconductor layer,

wherein the first, second and third semiconductor layers are spaced apart from each other in a first direction and a second direction, which are parallel to a top surface of the substrate,

the isolation structure comprises a plurality of isolation structures,

a first one of the plurality of the isolation structures is disposed between the first and second cell array structures, which are adjacent to each other in the first direction,

a second one of the plurality of isolation structures is disposed between the first and third cell array structures, which are adjacent to each other in the second direction, and

the plurality of isolation structures are spaced apart from each other.

16. The 3D semiconductor memory device of claim 14 , further comprising:

third and fourth semiconductor layers horizontally spaced apart from each other, on the substrate; and

third and fourth cell array structures disposed on the third and fourth semiconductor layers, respectively,

wherein the first, second, third and fourth semiconductor layers are spaced apart from each other in a first direction and a second direction, which are parallel to a top surface of the substrate, and

the isolation structure is disposed between the first and second cell array structures, which are adjacent to each other in the first direction, and is extended into a region between the third and fourth cell array structures, which are adjacent to each other in the first direction.

17. The 3D semiconductor memory device of claim 14 , further comprising:

peripheral circuits disposed on the substrate; and

a lower insulating layer covering the peripheral circuits,

wherein the first and second semiconductor layers and the isolation structure are disposed on the lower insulating layer, and

the first and second source structures of the first and second cell array structures are horizontally extended onto the lower insulating layer between the first and second semiconductor layers.

18. The 3D semiconductor memory device of claim 14 , wherein the first and second source structures of the first and second cell array structures are in contact with a side surface of the isolation structure.

19. The 3D semiconductor memory device of claim 14 , further comprising a buried insulating layer, which is disposed on the substrate and is between the first and second semiconductor layers,

wherein the isolation structure is disposed on the buried insulating layer, and

the first and second source structures of the first and second cell array structures are extended from the first and second semiconductor layers onto the buried insulating layer.

20. A three-dimensional (3D) semiconductor memory device, comprising:

first and second semiconductor layers separated from each other by a buried insulating layer;

a first cell array disposed on the first semiconductor layer, and a second cell array disposed on the second semiconductor layer; and

an isolation structure disposed on the buried insulating layer and separating the first and second cell arrays from each other,

wherein the first cell array comprises:

a plurality electrodes stacked in a direction perpendicular to a top surface of the first semiconductor layer; and

a source structure disposed between the first semiconductor layer and a lowermost one of the electrodes,

wherein the source structure overlaps the buried insulating layer.