Memory device and method of manufacturing the same

1. A memory device comprising:

an insulating structure including a first surface and a protrusion portion protruding from the first surface in a first direction;

a recording material layer on the insulating structure, the recording material layer extending along a protruding surface of the protrusion portion to cover the protrusion portion and extending onto the first surface of the insulating structure;

a channel layer on the recording material layer and extending along a surface of the recording material layer;

a gate insulating layer on the channel layer; and

a gate electrode on the gate insulating layer at a location facing a second surface of the insulating structure, the second surface of the insulating structure being a protruding upper surface of the protrusion portion.

2. The memory device of claim 1 , wherein a length from the first surface to the second surface in the first direction is greater than or equal to about 5 nm.

3. The memory device of claim 1 , wherein the first surface and the second surface are parallel with each other.

4. The memory device of claim 1 , wherein the recording material layer includes a variable resistance material.

5. The memory device of claim 4 , wherein the recording material layer includes any one of Rb 2 O, TiO 2 , BaO, ZrO 2 , CaO, HfO 2 , SrO, Sc 2 O 3 , MgO, Li 2 O, Al 2 O 3 , SiO 2 , BeO, Sc 2 O 3 , Nb 2 O 5 , NiO, Ta 2 O 5 , WO 3 , V 2 O 5 , La 2 O 3 , Gd 2 O 3 , CuO, MoO 3 , Cr 2 O 3 , and MnO 2 .

6. The memory device of claim 1 , wherein the recording material layer includes a phase-change material.

7. The memory device of claim 6 , wherein the recording material layer includes Ge 2 Sb 2 Te 5 .

8. The memory device of claim 1 , wherein a thickness of the recording material layer is about 0.5 nm to about 30 nm.

9. The memory device of claim 1 , further comprising:

a plurality of gate electrodes on the insulating structure, wherein

the insulating structure includes a plurality of protrusion portions spaced apart from each other in a second direction perpendicular to the first direction,

the protrusion portion is one of the plurality of protrusion portions,

the gate electrode is one of the plurality of gate electrodes,

the plurality of gate electrodes face the plurality of protrusion portions, respectively, and

the plurality of gate electrodes are spaced apart from each other in the second direction.

10. The memory device of claim 9 , wherein a length of the gate electrode in the second direction is about 5 nm to about 30 nm.

11. The memory device of claim 9 , wherein a distance between adjacent gate electrodes among the plurality of gate electrodes is about 5 nm to about 30 nm.

12. The memory device of claim 9 , further comprising:

an isolating layer between adjacent gate electrodes among the plurality of gate electrodes.

13. The memory device of claim 9 , wherein

an area of the recording material layer includes a plurality of switching areas respectively facing the plurality of gate electrodes,

each of the plurality of switching areas have both ends in the second direction, and

the both ends of the plurality of switching areas each contact the channel layer.

14. The memory device of claim 13 , wherein an electrical distance between adjacent switching areas from among the plurality of switching areas is greater than a physical distance between the adjacent switching areas.

15. The memory device of claim 14 , wherein, when

a protrusion length of the protrusion portion is D r ,

the electrical distance between the adjacent switching areas is greater than the physical distance by 2D r .

16. The memory device of claim 14 , wherein a length in the second direction of a corresponding switching area among the plurality of switching areas is less than a length of the gate electrode in the second direction.

17. The memory device of claim 9 , wherein

the plurality of protrusion portions of the insulating structure surround a cylindrical surface by a width and protrude in a radial direction, and

a longitudinal direction of the cylindrical surface corresponds to the second direction.

18. The memory device of claim 17 , further comprising:

a common source line; and

a bit line, wherein

an end of the recording material layer and the channel layer in the second direction are connected to the common source line and an other end the recording material layer and the channel layer is connected to the bit line, and

the plurality of gate electrodes are connected to a plurality of words lines, respectively.

19. An electronic device, comprising:

the memory device of claim 1 .

20. A memory device comprising:

an insulating structure including a first surface and a protrusion portion protruding from the first surface in a first direction;

a gate insulating layer conformally covering the first surface and the protrusion portion of the insulating structure;

a recording material layer extending between the gate insulating layer and both the first surface and the protrusion portion of the insulating structure;

a channel layer extending between the recording material layer and both the first surface and the protrusion portion of the insulating structure; and

a gate electrode on the gate insulating layer at a location facing a second surface of the insulating structure, the second surface of the insulating structure being a surface of the protrusion portion that is spaced apart from the first surface of the insulating structure in the first direction.