Organic electro-luminescence display device

1. A top-emission organic electro-luminescence display device in which an element substrate having a display region in which pixels each having an organic electro-luminescence layer sandwiched between an upper electrode and a lower electrode are formed in a matrix form is sealed by a sealing substrate and an image is formed on a side of the sealing substrate, wherein

the organic electro-luminescence layer comprises an electron transporting layer, a light emitting layer, and a hole transporting layer, wherein the electron transporting layer is formed through co-evaporation of an organic material and an alkali metal or an alkaline earth metal, and

a desiccant which comprises a material identical to the material of the electron transporting layer and comprises a co-evaporation layer having a greater composition ratio of the alkali metal or the alkaline earth metal than the electron transporting layer is placed without overlapping the light emitting layer.

2. The top-emission organic electro-luminescence display device according to claim 1 , wherein

the composition ratio of the alkali metal or the alkaline earth metal in the desiccant comprising the co-evaporation layer is greater than the composition ratio of the alkali metal or the alkaline earth metal in the electron transporting layer by greater than or equal to 50%.

3. A top-emission organic electro-luminescence display device in which an element substrate having a display region in which pixels each having an organic electro-luminescence layer sandwiched between an upper electrode and a lower electrode are formed in a matrix form is sealed by a sealing substrate and an image is formed on a side of the sealing substrate, wherein

the organic electro-luminescence layer comprises an electron transporting layer, a light emitting layer, and a hole transporting layer, wherein the electron transporting layer is formed through co-evaporation of an organic material and cesium, and

a desiccant which comprises a material identical to the material of the electron transporting layer and comprises a co-evaporation layer having a greater composition ratio of cesium than the electron transporting layer is placed without overlapping the light emitting layer.

4. The top-emission organic electro-luminescence display device according to claim 3 , wherein

the composition ratio of cesium in the desiccant comprising the co-evaporation layer is greater than the composition ratio of cesium in the electron transporting layer by greater than or equal to 50%.

5. The top-emission organic electro-luminescence display device according to claim 3 , wherein

the composition ratio of cesium in the desiccant comprising the co-evaporation layer is greater than the composition ratio of cesium in the electron transporting layer by greater than or equal to 100%.

6. The top-emission organic electro-luminescence display device according to claim 3 , wherein

an amount of composition of cesium in the desiccant comprising the co-evaporation layer is greater than or equal to 0.225 g/cm 3 .

7. A top-emission organic electro-luminescence display device in which an element substrate having a display region in which pixels each having an organic electro-luminescence layer sandwiched between an upper electrode and a lower electrode are formed in a matrix form is sealed by a sealing substrate and an image is formed on a side of the sealing substrate, wherein

the lower electrode is formed over an organic passivation film, the organic electro-luminescence layer is formed inside a region defined by a bank, and the upper electrode extends also over the bank,

the organic electro-luminescence layer comprises an electron transporting layer, a light emitting layer, and a hole transporting layer, wherein the electron transporting layer is formed through co-evaporation of an organic material and cesium, and

a desiccant which comprises a material identical to the material of the electron transporting layer and comprises a co-evaporation layer having a greater composition ratio of cesium than the electron transporting layer is placed without overlapping the light emitting layer.

8. The top-emission organic electro-luminescence display device according to claim 7 , wherein

the desiccant comprising the co-evaporation layer is formed over the organic passivation film.

9. The top-emission organic electro-luminescence display device according to claim 7 , wherein

the desiccant comprising the co-evaporation layer is formed over the upper electrode.

10. The top-emission organic electro-luminescence display device according to claim 7 , wherein

the bank comprises an organic film, and the desiccant comprising the co-evaporation layer is formed over the bank and over the upper electrode.

11. The top-emission organic electro-luminescence display device according to claim 7 , wherein

the bank comprises an inorganic film, and the desiccant comprising the co-evaporation layer is formed over the bank and over the upper electrode.

12. The top-emission organic electro-luminescence display device according to claim 7 , wherein

an auxiliary electrode comprising a metal extends over the bank, and the desiccant comprising the co-evaporation layer extends over the auxiliary electrode.

13. The top-emission organic electro-luminescence display device according to claim 7 , wherein

an auxiliary electrode comprising a metal extends over a first one of the bank, the desiccant comprising the co-evaporation layer extends over a second one of the bank, and the auxiliary electrode and the desiccant comprising the co-evaporation layer do not contact each other.