The partition 370 is formed by dry etching the inorganic material layer 370′ for the partition depending on the photoresist (PR) pattern. Such dry etching process may be performed in a vacuum chamber, and an etching gas such as sulfur hexafluoride (SF₆), nitrogen trifluoride (NF₃), or argon (Ar) may be used.

In an organic light emitting diode display according to a comparative example, which does not include the etch stop layer 210, since the upper layer of the pixel electrode 190 is formed to have a thickness of 70 ? to 120 ?, particles or fine gaps may be formed in the upper layer. In this case, when the particles and the like are exposed to the dry etching gas, silver (Ag) in the intermediate layer of the pixel electrode 190 reacts with the etching gas to form silver oxide (Ag₂O), silver fluoride (AgF), or the like, and thus, silver oxide (Ag₂O), silver fluoride (AgF), or the like is included in the intermediate layer. Therefore, the electrical and light emitting characteristics of the organic light emitting diode display of the comparative example deteriorate.

However, since the etch stop layer 210 is disposed at an upper portion of an edge of the pixel electrode 190 according to the present exemplary embodiment, the pixel electrode 190 is not affected by the etching gas. In addition, since the etch stop layer 210 is formed of a compound having low reactivity with the etching gas, the etch stop layer 210 is not affected by the dry etching process.