Patent ID: 8772074

Claim:
A method for manufacturing an organic light emitting display device, comprising: forming a transistor on a substrate; forming a first insulation layer on the transistor; forming a metal shield layer on the first insulation layer, the metal shield layer directly on and physically contacting one of a source electrode and a drain electrode of the transistor; forming a second insulation layer on the metal shield layer; forming a cathode on the second insulation layer to be directly connected to the another one of the source electrode and the drain electrode of the transistor; after forming the cathode, forming a bank layer having an opening on the cathode; performing plasma pretreatment on the cathode to remove an oxide layer that is naturally formed on a surface of the cathode and to suppress an oxidation of the surface of the cathode; forming a metal buffer layer directly on and physically contacting the cathode at the opening of the bank layer to prevent the oxidation of the cathode and to improve electron injection efficiency; forming an organic light emitting layer directly on and contacting the metal buffer layer; and forming an anode on the organic light emitting layer, wherein a thickness of the metal buffer layer is approximately 1 Å to 50 Å, wherein in said performing plasma pretreatment, one of nitrogen plasma and argon plasma is used, wherein said performing plasma pretreatment and said forming the metal buffer are consecutively performed in an identical chamber.