Electroluminescent display device

1. An electroluminescent display device comprising:

a first substrate and a second substrate facing each other; and

a dam structure bonding the first and second substrates with each other at outer edges of the first and second substrates,

wherein the dam structure includes a barrier pattern that has a lower barrier pattern and an upper barrier pattern having multiple layers on the second substrate, and

wherein the lower barrier pattern includes:

a first lower barrier pattern on the first substrate;

a second lower barrier pattern formed on the first lower barrier pattern; and

a third lower barrier pattern formed on the second lower barrier pattern.

2. The electroluminescent display device according to claim 1 , wherein the lower barrier pattern and the upper barrier pattern disposed alternately with each other.

3. The electroluminescent display device according to claim 1 , wherein the lower barrier pattern has a thickness of 6˜8 μm, and the upper barrier pattern has a thickness of 6˜7.5 μm.

4. The electroluminescent display device according to claim 1 , wherein each of the lower barrier pattern and the upper barrier pattern has a width of about 5 μm, and the lower barrier pattern and the upper barrier pattern are provided at every interval of 10 μm.

5. The electroluminescent display device according to claim 1 , wherein the upper barrier pattern includes:

a first upper barrier pattern;

a second upper barrier pattern formed on the first upper barrier pattern; and

a third upper barrier pattern formed on the second upper barrier pattern.

6. The electroluminescent display device according to claim 1 , further comprising:

a thin film transistor array disposed on the first substrate;

a planarization layer covering the thin film transistor array;

a bank disposed on the planarization layer and defining an emission area;

an emission device layer disposed on the planarization layer; and

a first passivation layer covering the emission device layer,

wherein the first and second lower barrier patterns are formed of the same material as the planarization layer, the third power barrier pattern is formed of the same material as the bank, and the first passivation layer covers the first to third lower barrier patterns.

7. The electroluminescent display device according to claim 5 , further comprising first to third color filters disposed on the second substrate, wherein the first to third upper barrier patterns are formed of the same material as the first to third color filters.

8. The electroluminescent display device according to claim 7 , further comprising a black matrix disposed on the second substrate and preventing a light leakage among the first to third color filters, wherein the black matrix is disposed on the first upper barrier pattern.

9. The electroluminescent display device according to claim 8 , further comprising a second passivation layer contacting the first to third color filters and the black matrix.

10. The electroluminescent display device according to claim 9 , wherein the second passivation layer contacts the first to third upper barrier patterns.

11. An electroluminescent display device comprising:

first and second substrates facing each other; and

a dam structure preventing surface moisture from permeating into the electroluminescent display device from a lateral side and disposed at outer edges of inner surfaces of the first and second substrates,

wherein the dam structure includes lower and upper barrier patterns respectively disposed on the first and second substrates and disposed alternately with each other, and

wherein the lower barrier pattern includes:

a first lower barrier pattern;

a second lower barrier pattern formed on the first lower barrier pattern; and

a third lower barrier pattern formed on the second lower barrier pattern.

12. The electroluminescent display device according to claim 11 , wherein the upper barrier pattern includes:

a first upper barrier pattern;

a second upper barrier pattern formed on the first upper barrier pattern; and

a third upper barrier pattern formed on the second upper barrier pattern.

13. The electroluminescent display device according to claim 12 , further comprising:

a thin film transistor array disposed on the first substrate;

a planarization layer covering the thin film transistor array;

a bank disposed on the planarization layer and defining an emission area;

an emission device layer disposed on the planarization layer; and

a first passivation layer covering the emission device layer,

wherein the first and second lower barrier patterns are formed of the same material as the planarization layer, the third power barrier pattern is formed of the same material as the bank, and the first passivation layer covers the first to third lower barrier patterns.

14. The electroluminescent display device according to claim 13 , further comprising first to third color filters disposed on the second substrate, wherein the first to third upper barrier patterns are formed of the same material as the first to third color filters.

15. The electroluminescent display device according to claim 14 , further comprising a black matrix disposed on the second substrate and preventing a light leakage among the first to third color filters, wherein the black matrix is disposed on the first upper barrier pattern.

16. The electroluminescent display device according to claim 15 , further comprising a second passivation layer contacting the first to third color filters and the black matrix.

17. The electroluminescent display device according to claim 16 , wherein the second passivation layer contacts the first to third upper barrier patterns.