Semiconductor device

1. A semiconductor device, comprising:

a device region on a substrate;

an interlayer dielectric layer on the device region;

a first interface layer on a side of the interlayer dielectric layer;

a low-k dielectric layer spaced apart from the interlayer dielectric layer with the first interface layer and having a dielectric constant less than that of the interlayer dielectric layer; and

a conductive line in the low-k dielectric layer,

wherein the first interface layer comprises:

a first sub-interface layer in contact with the low-k dielectric layer; and

a second sub-interface layer in contact with the interlayer dielectric layer,

the second sub-interface layer having hydrogen permeability less than that of the first sub-interface layer, and

the first sub-interface layer includes SiCN, and the second sub-interface layer includes SiN.

2. The semiconductor device of claim 1 , further comprising a hydrogen supply layer on the interlayer dielectric layer.

3. The semiconductor device of claim 1 , wherein a dielectric constant of the first sub-interface layer is less than a dielectric constant of the second sub-interface layer.

4. The semiconductor device of claim 3 , wherein the dielectric constant of the first sub-interface layer is less than 6, and the dielectric constant of the second sub-interface layer is equal to or more than 6.

5. The semiconductor device of claim 1 , wherein a density of the second sub-interface layer is greater than a density of the first sub-interface layer.

6. The semiconductor device of claim 1 , wherein an interface adhesion force between the first sub-interface layer and the low-k dielectric layer is greater than an interface adhesion force between the second sub-interface layer and the low-k dielectric layer.

7. The semiconductor device of claim 1 , wherein

the interlayer dielectric layer is on the low-k dielectric layer,

the first sub-interface layer is in contact with a top surface of the low-k dielectric layer, and

the second sub-interface layer is in contact with a bottom surface of the interlayer dielectric layer.

8. The semiconductor device of claim 7 , wherein the first sub-interface layer is in contact with a top surface of the conductive line.

9. The semiconductor device of claim 1 , wherein

the low-k dielectric layer is on the interlayer dielectric layer,

the second sub-interface layer is in contact with a top surface of the interlayer dielectric layer, and

the first sub-interface layer is in contact with a bottom surface of the low-k dielectric layer.

10. The semiconductor device of claim 1 , wherein the low-k dielectric layer is a plurality of low-k dielectric layers, and

wherein the semiconductor device further comprises second interface layers between the plurality of low-k dielectric layers,

at least one of the second interface layers comprising a first sub-interface layer and a second sub-interface layer.

11. The semiconductor device of claim 1 , wherein the low-k dielectric layer is a plurality of low-k dielectric layers, and

the semiconductor device further comprises a second interface layer between the plurality of low-k dielectric layers,

the second interface layer comprising a plurality of first sub-interface layers and a second sub-interface layer between the plurality of first sub-interface layers.

12. The semiconductor device of claim 1 , wherein the second sub-interface layer is thicker than the first sub-interface layer.

13. The semiconductor device of claim 12 , wherein a thickness of the second sub-interface layer is about 2 times to about 10 times a thickness of the first sub-interface layer.

14. The semiconductor device of claim 1 , wherein the interlayer dielectric layer comprises a first interlayer dielectric layer and a second interlayer dielectric layer on the first interlayer dielectric layer, and

wherein the semiconductor device further comprises:

an upper conductive line in the second interlayer dielectric layer; and

a third interface layer between the first interlayer dielectric layer and the second interlayer dielectric layer.

15. The semiconductor device of claim 14 , wherein the third interface layer comprises a second sub-interface layer.

16. A semiconductor device, comprising:

a device region on a substrate;

a low-k dielectric layer on the device region and including a conductive line therein;

an upper interlayer dielectric layer on the low-k dielectric layer;

a hydrogen supply layer on the upper interlayer dielectric layer; and

an upper interface layer between the low-k dielectric layer and the upper interlayer dielectric layer,

wherein the upper interface layer comprises a first sub-interface layer and a second sub-interface layer on the first sub-interface layer,

the second sub-interface layer having hydrogen permeability less than that of the first sub-interface layer.

17. The semiconductor device of claim 16 , further comprising:

a lower interlayer dielectric layer below the low-k dielectric layer; and

a lower interface layer between the lower interlayer dielectric layer and the low-k dielectric layer,

wherein the lower interface layer comprises a second sub-interface layer and a first sub-interface layer that are sequentially stacked.

18. The semiconductor device of claim 16 , wherein the upper interface layer comprises a recession between the second sub-interface layer and the first sub-interface layer.

19. A semiconductor device, comprising:

a device region on a substrate;

a plurality of low-k dielectric layers on the device region, each of the plurality of low-k dielectric layers including a conductive line therein;

an interlayer dielectric layer on the low-k dielectric layers;

a hydrogen supply layer on the interlayer dielectric layer; and

an upper interface layer between the interlayer dielectric layer and an uppermost one of the low-k dielectric layers,

wherein the upper interface layer comprises a low-k dielectric interface layer and a hydrogen blocking layer on the low-k dielectric interface layer,

the hydrogen blocking layer having a density greater than that of the low-k dielectric interface layer.

20. The semiconductor device of claim 19 , wherein

a dielectric constant of the low-k dielectric interface layer is less than 6, and

a dielectric constant of the hydrogen blocking layer is equal to or more than 6.