Patent ID: 8183762

Claim:
An organic electroluminescent display device, comprising: first and second substrates facing each other; a plurality of gate lines, a plurality of data lines and a plurality of power lines on the first substrate, the gate and data lines crossing each other to define a plurality of pixel regions; a switching element and a driving element connected to each other in each pixel region; a first electrode connected to the driving element; an organic luminescent layer on the first electrode, the organic luminescent layer including, a hole injection layer, a hole transporting layer, an emission material layer, an electron transporting layer, and an electron injection layer in order, wherein the hole injection layer includes a crystallizable hole injection material and a hole transporting material, and the hole transporting layer includes the hole transporting material, wherein a volumetric ratio of the crystallizable hole injection material to the hole transporting material in the entire hole injection layer ranges from 5:1 to 30:1 to prevent over-crystallizing of the hole injection layer such that the hole injection layer has a more even surface than a hole injection layer which does not have the hole transporting material, and wherein the hole injection layer is in direct contact with the first electrode and the hole transporting layer; and a second electrode on the organic luminescent layer.