Nonvolatile memory device

1. A non-volatile memory device, comprising:

a channel layer that extends from a substrate in a vertical direction;

a plurality of interlayer dielectric layers and a plurality of gate electrodes that are alternately stacked along the channel layer; and

a memory layer that is interposed between the channel layer and each of the gate electrodes,

wherein the memory layer comprises, between the channel layer and each of the gate electrodes:

a tunnel dielectric layer contacting the channel layer,

a charge blocking layer contacting the gate electrode,

a first charge trap layer contacting the tunnel dielectric layer and formed of an insulating material,

a second charge trap layer contacting the charge blocking layer and formed of an insulating material, and

a charge storage layer interposed between the first charge trap layer and the second charge trap layer, and formed of a semiconducting material or a conductive material.

2. The nonvolatile memory device of claim 1 , wherein one charge storage layer interposed between one gate electrode and the channel layer and another charge storage layer interposed between another gate electrode and the channel layer are separated from each other.

3. The nonvolatile memory device of claim 1 , wherein the tunnel dielectric layer extends in the vertical direction along the channel layer.

4. The nonvolatile memory device of claim 1 , wherein one second charge trap layer interposed between one gate electrode and the channel layer and another second charge trap layer interposed between another gate electrode and the channel layer are separated from each other.

5. The nonvolatile memory device of claim 1 , wherein one charge blocking layer interposed between one gate electrode and the channel layer and another charge blocking layer interposed between another gate electrode and the channel layer are separated from each other.

6. The nonvolatile memory device of claim 1 , one sidewall of each of the charge storage layer, the second charge trap layer and the charge blocking layer contacts the first charge trap layer,

the second charge trap layer surrounds upper and lower surfaces and the other sidewall of the charge storage layer, and

the charge blocking layer surrounds upper and lower surfaces and the other sidewall of the second charge trap layer.

7. The nonvolatile memory device of claim 1 , one sidewall of each of the second charge trap layer, the charge blocking layer and the corresponding gate electrode faces the channel layer,

the second charge trap layer contacts the charge storage layer and surrounds upper and lower surfaces and one sidewall of the charge blocking layer, and

the charge blocking layer surrounds upper and lower surfaces and one sidewall of the gate electrode.

8. The nonvolatile memory device of claim 1 , further comprising:

a layer interposed between one charge storage layer and another charge storage layer adjacent to the one charge storage layer in the vertical direction, said layer formed of an oxide of the semiconducting material or an oxide of the conducting material.

9. The nonvolatile memory device of claim 1 , wherein a band gap size of the charge storage layer is smaller than that of the first and second charge trap layers.

10. The nonvolatile memory device of claim 1 , wherein the charge storage layer comprises a conductive layer, the conductive layer comprising a semiconducting material layer doped with p-type impurities or n-type impurities.

11. The nonvolatile memory device of claim 10 , wherein a doping concentration of the impurities in the charge storage layer is in a range of 1E18 atoms/cm 3 to 1E21 atoms/cm 3 .

12. The nonvolatile memory device of claim 1 , wherein the charge storage layer comprises one selected from the group consisting of a polysilicon layer, a germanium layer, a silicon germanium layer and a combination thereof, wherein the silicon germanium layer is a SixGe1−x layer having 0<x<1.

13. The nonvolatile memory device of claim 1 , wherein at least one of the first and second charge trap layers comprises at least one selected from the group consisting of a silicon nitride layer, an aluminum oxide layer, a zirconium oxide layer, a hafnium oxide layer, a lanthanum oxide layer, and a niobium oxide layer.

14. The nonvolatile memory device of claim 1 , wherein at least one of the first and second charge trap layers is formed with a silicon nitride layer, and a ratio of nitride to silicon in the silicon nitride layer is in a range of 0.6 to 1.45.

15. The nonvolatile memory device of claim 1 , wherein the first and the second charge trap layers and the charge storage layer are configured to respectively trap and store charges of the same type.

16. A non-volatile memory device, comprising:

a channel layer that extends from a substrate in a vertical direction;

a plurality of interlayer dielectric layers and a plurality of gate electrodes that are alternately stacked along the channel layer;

a tunnel dielectric layer interposed between the channel layer and a first charge trap layer, and extending in the vertical direction;

the first charge trap layer interposed between the tunnel dielectric layer and charge storage layers and formed of an insulating material, wherein the first charge trap layer extends in the vertical direction;

the charge storage layers interposed between the first charge trap layer and second charge trap layers and formed of a semiconducting material or a conductive material, wherein the charge storage layers face the corresponding gate electrodes and are separated from each other;

the second charge trap layers interposed between the corresponding charge storage layers and corresponding charge blocking layers and formed of an insulating material, wherein the second charge trap layers are separated from each other; and

the charge blocking layers interposed between the corresponding second charge trap layers and the corresponding gate electrodes, wherein the charge blocking layers are separated from each other.

17. The nonvolatile memory device of claim 16 , wherein one sidewall of each of the charge storage layers, the second charge trap layers and the charge blocking layers contacts the first charge trap layer,

each of the second charge trap layers surrounds upper and lower surfaces and the other sidewall of the corresponding charge storage layer, and

each of the charge blocking layers surrounds upper and lower surfaces and the other sidewall of the corresponding second charge trap layer.

18. The nonvolatile memory device of claim 16 , wherein one sidewall of each of the second charge trap layers, the charge blocking layers and the gate electrodes faces the channel layer,

each of the second charge trap layers surrounds upper and lower surfaces and one sidewall of the corresponding charge blocking layer, and

each of the charge blocking layers surrounds upper and lower surfaces and one sidewall of the corresponding gate electrode.

19. The nonvolatile memory device of claim 16 , further comprising:

a layer interposed between two charge storage layers which are adjacent in the vertical direction, said layer formed of an oxide of the semiconducting material or an oxide of the conducting material.