Method of fabricating an organic light emitting diode display device including a selective melting and drying process with an organic solvent
An organic light emitting diode display device, and method of fabricating an organic light emitting diode display device are discussed. The organic light emitting diode display device according to one embodiment includes a first electrode on a thin film transistor and connected to a drain electrode; an auxiliary electrode on a same layer as the first electrode; a bank layer covering edges of the first electrode and edges of the auxiliary electrode and having a transmissive hole corresponding and an auxiliary contact hole; a light emitting layer on the first electrode in the transmissive hole; a residual layer on the auxiliary electrode in the auxiliary contact hole. A central portion of the residual layer has a larger thickness than an edge portion of the residual layer. The organic light emitting diode display device further includes a second electrode on the light emitting layer and the residual layer.
1. A method of fabricating an organic light emitting diode display device, the method comprising:
forming a thin film transistor on a substrate;
forming a passivation layer on the thin film transistor;
forming a first electrode and an auxiliary electrode on the passivation layer, the first electrode connected to a drain electrode of the thin film transistor, and the auxiliary electrode spaced apart from the first electrode;
forming a bank layer having a transmissive hole exposing the first electrode and an auxiliary contact hole exposing the auxiliary electrode;
sequentially forming a hole injecting material layer and a hole transporting material layer over the substrate including the bank layer;
forming a light emitting material layer on the hole transporting material layer corresponding to the transmissive hole;
sequentially forming an electron transporting material layer and an electron injecting material layer over the substrate including the light emitting material layer;
selectively melting and drying the electron injecting material layer, the electron transporting material layer, the hole transporting material layer and the hole injecting material layer corresponding to the auxiliary contact hole using an organic solvent while the electron injecting and transporting material layers and the hole injecting and transporting material layers corresponding to the transmissive hole remain intact, thereby forming a residual layer on the auxiliary electrode in the auxiliary contact hole and forming a hole injecting layer, a hole transporting layer, an electron transporting layer and an electron injecting layer corresponding to the light emitting material layer in the transmissive hole,
wherein a thickness of a central portion of the residual layer is smaller than a thickness of an edge portion of the residual layer at the auxiliary contact hole; and
forming a second electrode on the electron injecting layer and the residual layer,
wherein the second electrode is electrically connected to the auxiliary electrode through the central portion of the residual layer at the auxiliary contact hole.
2. The method of claim 1 , wherein the forming the hole injecting material layer, the hole transporting material layer, the light emitting material layer, the electron transporting material layer and the electron injecting material layer includes forming each layer are formed by a vacuum deposition method.
3. The method of claim 1 , wherein the light emitting material layer is formed over the substrate, and
wherein the forming the residual layer includes selectively melting and drying the light emitting material layer corresponding to the auxiliary contact hole using the organic solvent.
4. The method of claim 1 , wherein the selectively melting and drying includes injecting the organic solvent by an inkjet printing method or a nozzle printing method.
5. The method of claim 1 , wherein the forming the residual layer includes controlling the thickness of the central portion of the residual layer at the auxiliary contact hole to be less than 200 Å to electrically connect the second electrode to the auxiliary electrode through the central portion of the residual layer at the auxiliary contact hole.
6. The method of claim 1 , wherein the thickness of the edge portion of the residual layer is more than 1.1 times the thickness of the central portion of the residual layer.