Patent Publication Number: US-2016248035-A1

Title: Light emitting display device and method of manufacturing the same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to and the benefit of Korean Patent Application No. 10-2015-0026583, filed on Feb. 25, 2015 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference. 
     BACKGROUND 
     1. Field 
     The present invention relates to a light emitting display device and method of manufacturing the same. 
     2. Description of the Prior Art 
     Among light emitting display devices, an organic light emitting display device is a self-luminous display device that has the features of wide viewing angle, superior contrast, and high response speed, and thus has been recognized as the next-generation display device. 
     An organic light emitting display device has an organic light emitting layer that is made of an organic light emitting material disposed between an anode electrode and a cathode electrode. When anode and cathode voltages are respectively applied to these electrodes, holes injected from the anode electrode move to the organic light emitting layer through a hole injection layer and a hole transport layer, and electrons move to the organic light emitting layer through an electron injection layer and an electron transport layer. In the organic light emitting layer, the electrons and the holes are recombined, and through this recombination, excitons are generated. As the generated excitons return from an excited state to a ground state, the organic light emitting layer emits light to display an image. 
     SUMMARY 
     The organic light emitting display device includes a pixel defining layer having an opening for exposing an anode electrode that is formed for each of pixels, and a hole injection layer, a hole transport layer, an organic light emitting layer, an electron transport layer, an electron injection layer, and a cathode electrode, which are formed on the anode electrode that is exposed through the opening of the pixel defining layer. In particular, the organic light emitting layer may be formed by discharging a light emitting solution including a light emitting material into the opening of the pixel defining layer using an inkjet printing method, a nozzle printing method, or the like. 
     On the other hand, to prevent or substantially prevent the light emitting solution from going out of the opening of the pixel defining layer when forming the light emitting layer by discharging the light emitting solution into the opening of the pixel defining layer (using, e.g., an inkjet printing method or a nozzle printing method), the pixel defining layer is formed to have a lyophobic property. 
     However, even when the pixel defining layer has the lyophobic property, the light emitting solution has a small wetting property to the pixel defining layer. Accordingly, the light emitting layer formed by discharging the light emitting solution into the opening of the pixel defining layer may have a thickness that decreases toward a side surface of the pixel defining layer from the anode electrode. In this case, a leakage current may occur between the anode electrode and the cathode electrode in the portion in which the thickness of light emitting layer is decreased. As a result, light emission efficiency of the light emitting layer may be reduced and display quality of the light emitting display device may deteriorate. 
     Accordingly, one aspect of the present invention is to provide a light emitting display device, which may decrease the deterioration of light emission efficiency of the light emitting layer by decreasing the leakage current occurring between the anode electrode and the cathode electrode, and thereby decrease the deterioration of display quality. 
     Another aspect of the present invention is to provide a method of manufacturing a light emitting display device, which may decrease the deterioration of light emission efficiency of the light emitting layer by decreasing the leakage current occurring between the anode electrode and the cathode electrode, and thereby decrease the deterioration of display quality. 
     Additional aspects and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. 
     In accordance with one embodiment of the present invention, there is provided a light emitting display device including: a substrate including a plurality of pixels arranged in a first direction and a second direction crossing the first direction; a first electrode for each of the plurality of pixels on the substrate; a pixel defining layer on the substrate and having an opening exposing the first electrode; a light emitting layer extending along a side surface of the pixel defining layer from the first electrode in the opening of the pixel defining layer, and including a first portion located on the first electrode and a second portion located on the side surface of the pixel defining layer, the second portion having a thickness decreasing in a direction toward an upper surface of the pixel defining layer from the side surface of the pixel defining layer; a second electrode on the light emitting layer; and a leakage current blocking layer having a uniform thickness on the side surface of the pixel defining layer between the first electrode and the light emitting layer or between the light emitting layer and the second electrode. 
     In an embodiment, the leakage current blocking layer has an electric resistance higher than an electric resistance of the light emitting layer. 
     In an embodiment, the leakage current blocking layer includes an organic insulating material or an inorganic insulating material. 
     In an embodiment, the leakage current blocking layer has a continuous form between adjacent ones of the pixels. 
     In an embodiment, the leakage current blocking layer has first blocking portions and second blocking portions that cross, the first blocking portions extending along the second direction and between openings of the pixel defining layer separated along the first direction, and the second blocking portions extending along the first direction and between openings of the pixel defining layer separated along the second direction. 
     In an embodiment, the light emitting display device further includes a hole injection layer between the first electrode and the light emitting layer in the opening of the pixel defining layer, the hole injection layer having a thickness decreasing toward the side surface of the pixel defining layer from the first electrode, wherein the leakage current blocking layer is between the hole injection layer and the light emitting layer. 
     In an embodiment, the light emitting display device further includes a hole injection layer between the first electrode and the light emitting layer in the opening of the pixel defining layer, the hole injection layer having a thickness decreasing toward the side surface of the pixel defining layer from the first electrode, and a hole transport layer between the hole injection layer and the light emitting layer in the opening of the pixel defining layer, the hole transport layer having a thickness decreasing toward the side surface of the pixel defining layer from the first electrode, wherein the leakage current blocking layer is between the hole transport layer and the light emitting layer. 
     In an embodiment, the light emitting display device further includes an electron transport layer between the light emitting layer and the second electrode, wherein the leakage current blocking layer is between the light emitting layer and the electron transport layer. 
     In accordance with one embodiment of the present invention, there is provided a light emitting display device including: a substrate including a plurality of pixels arranged in a first direction and a second direction crossing the first direction; a first electrode for each of the plurality of pixels on the substrate; a pixel defining layer on the substrate and has an opening exposing the first electrode; a light emitting layer extending along a side surface of the pixel defining layer from the first electrode in the opening of the pixel defining layer; a second electrode on the light emitting layer; and a leakage current blocking layer extending from the side surface of the pixel defining layer to an upper surface of the pixel defining layer between the first electrode and the light emitting layer or between the light emitting layer and the second electrode and having a continuous form between adjacent pixels. 
     In an embodiment, the leakage current blocking layer has an electric resistance higher than an electric resistance of the light emitting layer. 
     In an embodiment, the leakage current blocking layer is formed of an organic insulating material or an inorganic insulating material. 
     In an embodiment, the leakage current blocking layer has first blocking portions and second blocking portions that cross, the first blocking portions extending along the second direction and between openings of the pixel defining layer separated along the first direction, and the second blocking portions extending along the first direction and between openings of the pixel defining layer separated along the second direction. 
     In an embodiment, the light emitting layer includes a first portion on the first electrode and a second portion on the side surface of the pixel defining layer, the second portion having a thickness decreasing in a direction toward an upper surface of the pixel defining layer from the side surface of the pixel defining layer. 
     In an embodiment, the light emitting display device further includes a hole injection layer between the first electrode and the light emitting layer in the opening of the pixel defining layer, the hole injection layer having a thickness decreasing toward the side surface of the pixel defining layer from the first electrode, wherein the leakage current blocking layer is between the hole injection layer and the light emitting layer. 
     In an embodiment, the light emitting display device further includes a hole injection layer between the first electrode and the light emitting layer in the opening of the pixel defining layer, the hole injection layer having a thickness decreasing toward the side surface of the pixel defining layer from the first electrode, and a hole transport layer between the hole injection layer and the light emitting layer in the opening of the pixel defining layer, the hole transport layer having a thickness decreasing toward the side surface of the pixel defining layer from the first electrode, wherein the leakage current blocking layer is between the hole transport layer and the light emitting layer. 
     In an embodiment, the light emitting display device further includes an electron transport layer between the light emitting layer and the second electrode, wherein the leakage current blocking layer is between the light emitting layer and the electron transport layer. 
     In accordance with one embodiment of the present invention, there is provided a method of manufacturing a light emitting display device, the method including: forming a first electrode, on a substrate including a plurality of pixels arranged in a first direction and a second direction that crosses the first direction, for each of the plurality of pixels; forming a pixel defining layer on the substrate and has an opening exposing the first electrode; forming a light emitting layer along a side surface of the pixel defining layer from the first electrode in the opening of the pixel defining layer, the light emitting layer including a first portion located on the first electrode and a second portion located on the side surface of the pixel defining layer, the second portion having a thickness decreasing in a direction toward an upper surface of the pixel defining layer from the side surface of the pixel defining layer; forming a second electrode on the light emitting layer; and forming a leakage current blocking layer, having a uniform thickness, on the side surface of the pixel defining layer between the first electrode and the light emitting layer or between the light emitting layer and the second electrode. 
     In an embodiment, the forming the leakage current blocking layer includes: disposing a first mask having first openings on the substrate, the first openings exposing side portions of the pixel defining layer facing each other in the first direction in the opening of the pixel defining layer; forming first blocking portions by depositing a material forming the leakage current blocking layer on a side surface and an upper surface of the pixel defining layer that are exposed through the first openings of the first mask using a deposition method; disposing a second mask having second openings on the substrate, the second openings exposing side portions of the pixel defining layer facing each other in the second direction in the opening of the pixel defining layer; and forming second blocking portions by depositing the material forming the leakage current blocking layer on a side surface and an upper surface of the pixel defining layer that are exposed through the second openings of the second mask using the deposition method. 
     In an embodiment, the first openings extend along the second direction and have a continuous form between adjacent openings of the pixel defining layer in the first direction, and the second openings extend along the first direction and have a continuous form between adjacent openings of the pixel defining layer in the second direction. 
     In an embodiment, the method further includes: forming a hole injection layer, between the first electrode and the light emitting layer in the opening of the pixel defining layer, having a thickness decreasing toward the side surface of the pixel defining layer from the first electrode; forming a hole transport layer, between the hole injection layer and the light emitting layer in the opening of the pixel defining layer, having a thickness decreasing toward the side surface of the pixel defining layer from the first electrode; and forming an electron transport layer between the light emitting layer and the second electrode in the opening of the pixel defining layer, wherein the forming the leakage current blocking layer includes disposing the leakage current blocking layer between the hole injection layer and the hole transport layer, between the hole transport layer and the light emitting layer, or between the light emitting layer and the electron transport layer. 
     According to embodiments of the present invention, at least the following effects may be achieved. 
     The light emitting display device according to an embodiment of the present invention includes the leakage current blocking layer, with a uniform thickness, disposed on the side surface of the pixel defining layer between the first electrode and the light emitting layer at a region where a distance between the first electrode and the second electrode becomes smaller due to the portion having a decreasing thickness in the light emitting layer. This is because the light emitting layer disposed in the opening of the pixel defining layer has decreasing thickness at the portion corresponding to the side surface of the pixel defining layer. 
     Accordingly, the light emitting display device according to an embodiment of the present invention may decrease the deterioration of light emission efficiency of the light emitting layer by decreasing or preventing the occurrence of a leakage current between the first electrode and the second electrode to thereby decrease the deterioration of display quality. 
     The effects according to the present invention are not limited to the contents as exemplified above, but further various effects are included in the description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other features and aspects of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a schematic plan view of a plurality of pixels of a light emitting display device according to an embodiment of the present invention; 
         FIG. 2  is a cross-sectional view taken along the line I-I′ of  FIG. 2 ; 
         FIG. 3  is an enlarged cross-sectional view of portion A of  FIG. 2 ; 
         FIG. 4  is a plan view of a leakage current blocking layer of  FIG. 2 ; 
         FIG. 5  is cross-sectional view of a light emitting display device according to another embodiment of the present invention; 
         FIG. 6  is cross-sectional view of a light emitting display device according to still another embodiment of the present invention; 
         FIG. 7  is cross-sectional view of a light emitting display device according to still another embodiment of the present invention; 
         FIG. 8  is cross-sectional view of a light emitting display device according to still another embodiment of the present invention; 
         FIG. 9  is cross-sectional view of a light emitting display device according to still another embodiment of the present invention; and 
         FIGS. 10 through 20  are views illustrating a method of manufacturing a light emitting display device according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Aspects and features of the present invention and methods of accomplishing the same may be understood more readily by reference to the following detailed description of exemplary embodiments and the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concept of the invention to those skilled in the art, and the present invention will be defined by the appended claims, and equivalents thereof. 
     Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. 
       FIG. 1  is a schematic plan view of a plurality of pixels of a light emitting display device according to an embodiment of the present invention.  FIG. 2  is a cross-sectional view taken along the line I-I′ of  FIG. 2 .  FIG. 3  is an enlarged cross-sectional view of portion A of  FIG. 2 .  FIG. 4  is a plan view of a leakage current blocking layer of  FIG. 2 . 
     Referring to  FIGS. 1 and 2 , a light emitting display includes a substrate  105 , a first electrode  110 , a pixel defining layer  120 , a hole injection layer  130 , a leakage current blocking layer  140 , a hole transport layer  150 , a light emitting layer  160 , an electron transport layer  170 , an electron injection layer  180 , and a second electrode  190 . These layers (or members) are sequentially stacked along a Z direction of  FIG. 2 . 
     The substrate  105  includes a display area DA including a plurality of pixels PX displaying an image and a non-display area NDA located outside the display area DA. The pixels PX are disposed along a first direction X and a second direction Y, which crosses the first direction X, to have a matrix form, and include red pixels that emit red light, green pixels that emit green light, and blue pixels that emit blue light. As shown in  FIG. 2 , a non-pixels region NPX is defined between adjacent pixels PX in the display area DA of the substrate  105 . 
     The substrate  105  may include an insulating substrate. The insulating substrate may be formed of a transparent glass material having SiO 2  as a main component. In some embodiments, the insulating substrate may be made of an opaque material, a plastic material, and/or the like. Further, the insulating substrate may be a flexible substrate. 
     The substrate  105  may further include other structures formed on the insulating substrate. Examples of the structures include wirings, electrodes, and insulating layers. In some embodiments, the substrate  105  may include a plurality of thin-film transistors (TFTs) formed on the insulating substrate. Drain electrode of a TFT may be electrically connected to the first electrode  110 . Each of the TFTs may include an active region made of amorphous silicon, polycrystalline silicon, monocrystalline silicon, and/or the like. In another embodiment, each of the TFTs may include an active region made of an oxide semiconductor. 
     The first electrode  110  is formed for each pixel PX on the substrate  105 . The first electrode  110  may be an anode electrode, which provides holes to the light emitting layer  160  in response to a signal transmitted to a corresponding TFT, or a cathode electrode, which provides electrons to the light emitting layer  160  in response to the signal transmitted to the TFT. The first electrode  110  may be used as a transparent electrode or a reflective electrode. To be used as a transparent electrode, the first electrode  110  may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), In 2 O 3 , and/or the like. To be used as a reflective electrode, the first electrode  110  may be formed by forming a reflective film using Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, and/or the like, or a compound of the same, and then forming ITO, IZO, ZnO, In 2 O 3 , and/or the like on the reflective film. The first electrode  110  may be formed by, for example, a photolithography method, or may be formed by any other suitable method. 
     The pixel defining layer  120  is disposed on the substrate  105  so as to have an opening OP exposing the first electrode  110  to partition respective pixels PX. The pixel defining layer  120  enables the hole injection layer  130  to be formed on the first electrode  110  through the opening OP. The pixel defining layer  120  may be made of an insulating material. 
     In an embodiment of the present invention, the pixel defining layer  120  is formed to have a lyophobic property in order to prevent or substantially prevent a hole injection solution from leaving (e.g., going out of) the opening OP of the pixel defining layer  120  when forming the hole injection layer  130  by discharging the hole injection solution into the opening OP of the pixel defining layer  120  using an ink printing method, a nozzle printing method, or the like. The pixel defining layer  120  may be formed of an insulating material that makes the contact angle of the hole injection solution against the pixel defining layer  120  become greater than or equal to about 40°. For example, the pixel defining layer  120  may be formed of an organic insulating material including fluorine, and/or the like. The organic insulating material may be at least one polymer resin selected from the group including benzo cyclo butane (BCB), polyimide (PI), poly amaide (PA), acryl resin, phenol resin, and/or the like. The pixel defining layer  120  may be formed by a photolithography method, but is not limited thereto. The inkjet printing method refers to dropping a material to be printed at a desired location in the form of ink droplets, and the nozzle printing method refers to making a material to be flowed in the form of a solution along a line including a desired location. 
     The hole injection layer  130  is disposed along the first electrode  110  and the side surface of the pixel defining layer  120  in the opening OP of the pixel defining layer  120 . The hole injection layer  130  is formed by discharging a hole injection solution including a hole injection material into the opening OP of the pixel defining layer  120  using an inkjet printing method, a nozzle printing method, or the like. In this case, the hole injection layer  130  may have a thickness decreasing toward the side surface of the pixel defining layer  120  from the first electrode  110 . This is because the hole injection solution has a small wetting property to the pixel defining layer  120  although the pixel defining layer  120  has a lyophobic property. For example, the hole injection layer  130  may include a first portion located on the first electrode  110  and a second portion located on the side surface of the pixel defining layer  120 . The first portion may have a uniform thickness, and the second portion may have a thickness decreasing in a direction toward the upper surface of the pixel defining layer  120  from the side surface of the pixel defining layer  120 . 
     The hole injection layer  130  is a buffer layer that lowers an energy barrier between the first electrode  110  and the hole transport layer  150 . The hole injection layer  130  facilitates the injection of holes from the first electrode  110  to the hole transport layer  150 . The hole injection layer  130  is formed to be an organic compound such as 4,4′,4″-tris(3-methylphenylphenylamino)triphenylamine (MTDATA), copper phthalocyanine (CuPc), or poly(3,4-ethylenedioxythiphene, polystyrene sulfonate) (PEDOT/PSS), and/or the like. 
     The leakage current blocking layer  140  is disposed on the side surface of the pixel defining layer  120  between the first electrode  110  and the light emitting layer  160 . For example, the leakage current blocking layer  140  may be disposed on the side portion of the hole injection layer  130 , at a region in which the side portion of the hole injection layer  130  is disposed on the side surface of the pixel defining layer  120 . Accordingly, the leakage current blocking layer  140  may be disposed at a region where a distance between the first electrode  110  and the second electrode  190  becomes smaller, which corresponds to the portion of the light emitting layer  160  having decreasing thickness (i.e., the second portion  160   b  of  FIG. 3 ). This is because the light emitting layer  160  disposed in the opening OP of the pixel defining layer  120  has decreasing thickness at the portion corresponding to the side surface of the pixel defining layer  120 . Thus, the leakage current blocking layer  140  may decrease or prevent the occurrence of a leakage current between first electrode  110  and the second electrode  190 , which may otherwise result from the thinned portion (the second portion  160   b  of  FIG. 3 ) of the light emitting layer  160 . In the example shown in  FIG. 3 , the element having a thickness decreasing at the portion corresponding to the side surface of the pixel defining layer  120  is the light emitting layer  160 , however, the element may include at least one of the hole injection layer  130  and the hole transport layer  150 . 
     In some embodiments, the leakage current blocking layer  140  may not be formed on a portion of the light emitting layer  160  having increased thickness (i.e., the first portion  160   a  of  FIG. 3 ). 
     The leakage current blocking layer  140  is formed to have a lyophobic property in order to prevent or substantially prevent a hole transport solution from going out of (or reaching beyond) the opening OP of the pixel defining layer  120  when forming the hole transport layer  150 . The leakage current blocking layer  140  may be formed by discharging the hole transport solution into the opening OP of the pixel defining layer  120  using an ink printing method, a nozzle printing method, or the like, while having an electric resistance higher than an electric resistance of the light emitting layer  160  to prevent or substantially prevent a leakage current from flowing between the first electrode  110  and the second electrode  190 . Thus, the leakage current blocking layer  140  may be formed of an insulating material that makes the contact angle of the hole transport solution against the leakage current blocking layer  140  become greater than or equal to about 40°. For example, the leakage current blocking layer  140  may be formed of an organic insulating material including fluorine, and/or the like. The organic insulating material may be at least one polymer resin selected from the group including benzo cyclo butane (BCB), polyimide (PI), poly amaide (PA), acryl resin, phenol resin, and the like. 
     The leakage current blocking layer  140  may have a uniform thickness T. Accordingly, the leakage current blocking layer  140  may decrease or prevent the occurrence of a leakage current between first electrode  110  and the second electrode  190  by reducing the region where the interval between the first electrode  110  and the second electrode  190  is decreased, which may occur in a case that the light emitting layer  160  disposed in the opening OP of the pixel defining layer  120  has a thickness decreasing toward the side surface of the pixel defining layer  120  from the first electrode  110 , and may also occur in a case that the light emitting layer  160  has a thin thickness on the side surface of the pixel defining layer  120  due to its other pattern such as uneven shape. The leakage current blocking layer  140  may be formed using a deposition method to have the uniform thickness T. The deposition method may be a method through which it is easy to control forming the leakage current blocking layer  140  at a desire position. As the deposition method, an evaporation deposition method evaporating a deposition material to deposit at a desire position may be selected. 
     The leakage current blocking layer  140  may be formed to extend from the side surface of the pixel defining layer  120  to the upper surface of the pixel defining layer  120  so as to have a continuous form between the adjacent pixels PX in a plan view. In this case, as illustrated in  FIG. 4 , the leakage current blocking layer  140  may be formed such that first blocking portions  140   a  and second blocking portions  140   b  cross, in which the first blocking portions  140   a  extend along the second direction Y on the upper surface of the pixel defining layer  120  and are disposed between openings OP of the pixel defining layer  120  separated along the first direction X, and the second blocking portions  140   b  extended along the first direction X on the upper surface of the pixel defining layer  120  and are disposed between openings OP of the pixel defining layer  120  separated along the second direction Y. 
     The hole transport layer  150  may be disposed on the hole injection layer  130  and the leakage current blocking layer  140  in the opening OP of the pixel defining layer  120 . The hole transport layer  150  may be formed by discharging a hole transport solution including a hole transport material into the opening OP of the pixel defining layer  120  using an inkjet printing method, a nozzle printing method, or the like. In this case, the hole transport layer  150  may have a thickness decreasing toward the side surface of the pixel defining layer  120  from the first electrode  110 . This is because the hole transport solution has a small wetting property to the leakage current blocking layer  140  although the leakage current blocking layer  140  has a lyophobic property. For example, the hole transport layer  150  may include a first portion located on the first electrode  110  and a second portion located on the side surface of the pixel defining layer  120 . The first portion may have a uniform thickness, and the second portion may have a thickness decreasing in a direction toward the upper surface of the pixel defining layer from the side surface of the pixel defining layer  120 . 
     The hole transport layer  150  transports holes provided from the hole injection layer  130  to the light emitting layer  160 . The hole transport layer  150  is formed of the hole transport material having an electrical conductivity lower than that of the hole injection layer  130 . The hole transport layer  150  may be formed of an organic compound such as N,N′-diphenyl-N,N′-bis(3-methylphenyl)-1,1′-bi-phenyl-4,4′-diamine (TPD) or N,N′-di(naphthalen-1-yl)-N,N′-diphenyl-benzidine (NPB), and/or the like. 
     The light emitting layer  160  may be disposed on the hole transport layer  150  in the opening OP of the pixel defining layer  120 . The light emitting layer  160  may be formed by discharging a light emitting solution including a light emitting material into the opening OP of the pixel defining layer  120  using an inkjet printing method, a nozzle printing method, or the like. In this case, the light emitting layer  160  may have a thickness decreasing toward the side surface of the pixel defining layer  120  from the first electrode  110 . This is because the light emitting solution has a small wetting property to the leakage current blocking layer  140  although the leakage current blocking layer  140  has a lyophobic property. For example, the light emitting layer  160  may include a first portion  160   a  located on the first electrode  110  and a second portion  160   b  located on the side surface of the pixel defining layer  120 . The first portion  160   a  may have a uniform thickness, and the second portion  160   b  may have a thickness decreasing in a direction toward the upper surface of the pixel defining layer from the side surface of the pixel defining layer  120 . 
     The light emitting layer  160  emits light when holes received from the first electrode  110  and electrons received from the second electrode  190  recombine. More For example, holes and electrons provided to the light emitting layer  160  may combine to form excitons. When the excitons change from an excited state to a ground state, the light emitting layer  160  may emit light. The light emitting layer  160  may be formed of a light emitting material having an electrical conductivity that is lower than an electrical conductivity of the hole injection layer  130  and is similar to the electrical conductivity of the hole transport layer  150 . The light emitting layer  160  may include a red light emitting layer that emits red light, a green light emitting layer that emits green light, and a blue light emitting layer that emits blue light. 
     The red light emitting layer may include one red light emitting material or a host and a red dopant. Examples of the host of the red light emitting layer may include, but are not limited to, Alq 3 , 4,4′-N,N′-dicarbazol-biphenyl (CBP), ploy(n-vinylcarbazole) (PVK), 9,10-Di(naphthyl-2-yl)anthracene (ADN), 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBI), 3-tert-butyl-9,10-di(naphth-2-yl) anthracene (TBADN), terfluorene (E3), distyrylarylene (DSA). In addition, examples of the red dopant may include, but are not limited to, PtOEP, Ir(piq) 3 , and Btp 2 Ir(acac). 
     The green light emitting layer may include one green light emitting material or a host and a green dopant. The host of the red light emitting layer may be used as the host of the green light emitting layer. Examples of the green dopant may include, but are not limited to, Ir(ppy) 3 , Ir(ppy) 2 (acac), and Ir(mpyp) 3 . 
     The blue light emitting layer may include one blue light emitting material or a host and a blue dopant. The host of the red light emitting layer may be used as the host of the blue light emitting layer. Examples of the blue dopant may include, but are not limited to, F 2 Irpic, (F 2 ppy) 2 Ir(tmd), Ir(dfppz) 3 , ter-fluorene, 4,4′-bis(4-diphenylaminostyryl) biphenyl (DPAVBi), 2,5,8,11-tetra-ti-butyl pherylene (TBPe). 
     The electron transport layer  170  may be disposed on the light emitting layer  160  to have a continuous form between the adjacent pixels PX. The electron transport layer  170  transports electrons provided from the second electrode  190  via the electron injection layer  180  to the light emitting layer  160 . The electron transport layer  170  may be formed of an organic compound such as 4,7-diphenyl-1,10-phenanthroline) (Bphen), BAlq, tris(8-quinolinorate)aluminum (Alq3), berylliumbis(benzoquinolin-10-olate) (Bebq 2 ), TPBI, and/or the like. The electron transport layer  170  may be formed by, for example, a deposition method, or any other suitable method. 
     The electron injection layer  180  may be disposed on the electron transport layer  170 . The electron injection layer  180  is a buffer layer that lowers an energy barrier between the electron transport layer  170  and the second electrode  190 . The electron injection layer  180  facilitates the injection of electrons from the second electrode  190  to the electron transport layer  170 . The electron injection layer  180  may be formed of LiF, CsF, and/or the like. The electron injection layer  180  may be formed by, for example, a deposition method, or any other suitable method. 
     The second electrode  190  may be formed on the electron injection layer  180  and may be a cathode electrode providing electrons to the light emitting layer  160  or an anode electrode providing holes to the light emitting layer  160 . Like the first electrode  110 , the second electrode  190  may be used as a transparent electrode or a reflective electrode. The second electrode  190  may be formed by, for example, a deposition method, or any other suitable method. 
     The light emitting display device  100  may further include an encapsulation substrate placed on the second electrode  190 . The encapsulation substrate may be made of an insulating substrate. A spacer may be disposed between the second electrode  190  on the pixel defining layer  120  and the encapsulation substrate. In some other embodiments of the present invention, the encapsulation substrate may be omitted. In this case, an encapsulation layer made of an insulating material may cover, and thus protect, the entire structure. 
     As described above, the light emitting display device  100  according to an embodiment of the present invention includes the leakage current blocking layer  140 , with a uniform thickness, disposed on the side surface of the pixel defining layer  120  between the first electrode  110  and the light emitting layer  160  at a region where a distance between the first electrode  110  and the second electrode  190  becomes smaller due to the portion having decreasing thickness in the light emitting layer  160 . This is because the light emitting layer  160  disposed in the opening OP of the pixel defining layer  120  has a decreasing thickness at the portion corresponding to the side surface of the pixel defining layer  120 . 
     Accordingly, the light emitting display device  100  according to an embodiment of the present invention may decrease the deterioration of light emission efficiency of the light emitting layer  160  by decreasing or preventing the occurrence of a leakage current between the first electrode  110  and the second electrode  190 , and thus the deterioration of display quality may be decreased. 
     Next, a light emitting display device  200  according to another embodiment of the present invention will be described. 
       FIG. 5  is cross-sectional view of a light emitting display device according to another embodiment of the present invention. 
     Referring to  FIG. 5 , the light emitting display device  200  according to another embodiment of the present invention has the same or substantially the same configuration as the configuration of the light emitting display device  100  of  FIG. 1  except for an electron transport layer  270 , an electron injection layer  280 , and a second electrode  290 . Accordingly, explanation of the light emitting display device  200  according to another embodiment of the present invention will be primarily focused on the electron transport layer  270 , the electron injection layer  280 , and the second electrode  290 . 
     The light emitting display device  200  according to another embodiment of the present invention includes substrate  105 , a first electrode  110 , a pixel defining layer  120 , a hole injection layer  130 , a leakage current blocking layer  140 , a hole transport layer  150 , a light emitting layer  160 , an electron transport layer  270 , an electron injection layer  280 , and a second electrode  290 . These members are sequentially stacked in a Z direction of  FIG. 5 . 
     The electron transport layer  270  is similar to the electron transport layer  170  of  FIG. 2 . However, the electron transport layer  270  is only disposed on the light emitting layer  160 . That is, the electron transport layer  170  is formed to have a divided form between the adjacent pixels PX. 
     The electron injection layer  280  is similar to the electron injection layer  180  of  FIG. 2 . However, the electron injection layer  280  is formed to correspond to the electron transport layer  270 , which is formed to have a divided form between the adjacent pixels PX. 
     The second electrode  290  is similar to the second electrode  190  of  FIG. 2 . However, the second electrode  290  contacts a partial portion of the leakage current blocking layer  140  exposed by the electron injection layer  280 , which is formed to have a divided form between the adjacent pixels PX. 
     As described above, the light emitting display device  200  according to another embodiment of the present invention includes the leakage current blocking layer  140 , with a uniform thickness, disposed on the side surface of the pixel defining layer  120  between the first electrode  110  and the light emitting layer  160  at a region where a distance between the first electrode  110  and the second electrode  190  becomes smaller due to the portion having a decreasing thickness in the light emitting layer  160 . This is because the light emitting layer  160  disposed in the opening OP of the pixel defining layer  120  has decreasing thickness at the portion corresponding to the side surface of the pixel defining layer  120 . 
     Accordingly, the light emitting display device  200  according to another embodiment of the present invention may decrease the deterioration of light emission efficiency of the light emitting layer  160  by decreasing or preventing the occurrence of a leakage current between the first electrode  110  and the second electrode  290 , and thus the deterioration of display quality may be decreased. 
     Next, a light emitting display device  300  according to still another embodiment of the present invention will be described. 
       FIG. 6  is cross-sectional view of a light emitting display device according to still another embodiment of the present invention. 
     Referring to  FIG. 6 , the light emitting display device  300  according to still another embodiment of the present invention has the same or substantially the same configuration as the configuration of the light emitting display device  100  of  FIG. 1  except for a leakage current blocking layer  340 , a hole transport layer  350 , and a light emitting layer  360 . Accordingly, explanation of the light emitting display device  300  according to still another embodiment of the present invention will be primarily focused on the leakage current blocking layer  340 , the hole transport layer  350 , and the light emitting layer  360 . 
     The light emitting display device  300  according to still another embodiment of the present invention includes substrate  105 , a first electrode  110 , a pixel defining layer  120 , a hole injection layer  130 , a leakage current blocking layer  340 , a hole transport layer  350 , a light emitting layer  360 , an electron transport layer  170 , an electron injection layer  180 , and a second electrode  190 . These members are sequentially stacked in a Z direction of  FIG. 6 . 
     The leakage current blocking layer  340  is similar to the leakage current blocking layer  140  of  FIG. 2 . However, the leakage current blocking layer  340  is disposed between the hole transport layer  350  and the light emitting layer  360 . The leakage current blocking layer  340  may have the same or substantially the same function as the leakage current blocking layer  140  of  FIG. 2 . 
     The hole transport layer  350  is similar to the hole transport layer  150  of  FIG. 2 . However, the hole transport layer  350  is disposed between the hole injection layer  130  and the leakage current blocking layer  340 . The hole transport layer  350  may have the same or substantially the same function as the hole transport layer  150  of  FIG. 2 . 
     The light emitting layer  360  is similar to the light emitting layer  160  of  FIG. 2 . However, the light emitting layer  360  is disposed on the hole transport layer  350  and the leakage current blocking layer  340  in the opening OP of the pixel defining layer  120 . The light emitting layer  360  may have the same or substantially the same function as the light emitting layer  160  of  FIG. 2 . 
     As described above, the light emitting display device  300  according to still another embodiment of the present invention includes the leakage current blocking layer  340 , with a uniform thickness, disposed on the side surface of the pixel defining layer  120  between the first electrode  110  and the light emitting layer  360  at a region where a distance between the first electrode  110  and the second electrode  190  becomes smaller due to the portion having a decreasing thickness in the light emitting layer  360 . This is because the light emitting layer  160  disposed in the opening OP of the pixel defining layer  120  has decreasing thickness at the portion corresponding to the side surface of the pixel defining layer  120 . 
     Accordingly, the light emitting display device  300  according to still another embodiment of the present invention may decrease the deterioration of light emission efficiency of the light emitting layer  360  by decreasing or preventing the occurrence of a leakage current between the first electrode  110  and the second electrode  190 , and thus the deterioration of display quality may be decreased. 
     The electron transport layer  270  and the electron injection layer  280  illustrated in  FIG. 5  may be applied to the light emitting layer  360  instead of the electron transport layer  170  and the electron injection layer  180 . 
     Next, a light emitting display device  400  according to still another embodiment of the present invention will be described. 
       FIG. 7  is cross-sectional view of a light emitting display device according to still another embodiment of the present invention. 
     Referring to  FIG. 7 , the light emitting display device  400  according to still another embodiment of the present invention has the same or substantially the same configuration as the configuration of the light emitting display device  100  of  FIG. 1  except for a first common layer  430 , a leakage current blocking layer  440 , and a light emitting layer  460 . Accordingly, explanation of the light emitting display device  400  according to still another embodiment of the present invention will be primarily focused on the first common layer  430 , the leakage current blocking layer  440 , and the light emitting layer  460 . 
     The light emitting display device  400  according to still another embodiment of the present invention includes substrate  105 , a first electrode  110 , a pixel defining layer  120 , a first common layer  430 , a leakage current blocking layer  440 , a light emitting layer  460 , an electron transport layer  170 , an electron injection layer  180 , and a second electrode  190 . These members are sequentially stacked in a Z direction of  FIG. 7 . 
     The first common layer  430  may be disposed along the first electrode  110  and the side surface of the pixel defining layer  120  in the opening OP of the pixel defining layer  120 . The first common layer  430  may be formed by discharging a first common solution including a first common material into the opening OP of the pixel defining layer  120  using an inkjet printing method, a nozzle printing method, or the like. In this case, the first common layer  430  may have a thickness decreasing toward the side surface of the pixel defining layer  120  from the first electrode  110 . The first common layer  430  may be the hole injection layer  130  or the hole transport layer  150  shown in  FIG. 2 . That is, the hole transport layer  150  or the hole injection layer  130  illustrated in  FIG. 2  may be omitted in the light emitting display device  400 . 
     The first common layer  430  may be applied to the light emitting display device  200  of  FIG. 5  in which the hole transport layer is omitted, instead of the hole injection layer  130 . 
     The leakage current blocking layer  440  is similar to the leakage current blocking layer  140  of  FIG. 2 . However, the leakage current blocking layer  440  may be disposed between the first common layer  430  and the light emitting layer  460 . The leakage current blocking layer  440  may have the same or substantially the same function as the leakage current blocking layer  140  of  FIG. 2 . 
     The light emitting layer  460  is similar to the light emitting layer  160  of  FIG. 2 . However, the light emitting layer  460  is disposed on the first common layer  430  and the leakage current blocking layer  440  in the opening OP of the pixel defining layer  120 . The light emitting layer  460  may have the same or substantially the same function as the light emitting layer  160  of  FIG. 2 . 
     As described above, the light emitting display device  400  according to still another embodiment of the present invention includes the leakage current blocking layer  440 , with a uniform thickness, disposed on the side surface of the pixel defining layer  120  between the first electrode  110  and the light emitting layer  460  at a region where a distance between the first electrode  110  and the second electrode  190  becomes smaller through the portion having a decreasing thickness in the light emitting layer  360 . This is because the light emitting layer  460  disposed in the opening OP of the pixel defining layer  120  has decreasing thickness at the portion corresponding to the side surface of the pixel defining layer  120 . 
     Accordingly, the light emitting display device  400  according to still another embodiment of the present invention may decrease the deterioration of light emission efficiency of the light emitting layer  460  by decreasing or preventing the occurrence of a leakage current between the first electrode  110  and the second electrode  190 , and thus the deterioration of display quality may be decreased. 
     Next, a light emitting display device  500  according to still another embodiment of the present invention will be described. 
       FIG. 8  is cross-sectional view of a light emitting display device according to still another embodiment of the present invention. 
     Referring to  FIG. 8 , the light emitting display device  500  according to still another embodiment of the present invention has the same or substantially the same configuration as the configuration of the light emitting display device  100  of  FIG. 1  except for a first common layer  430 , a leakage current blocking layer  440 , a light emitting layer  460 , a second common layer  570 , and a second electrode  590 . Accordingly, explanation of the light emitting display device  500  according to still another embodiment of the present invention will be primarily focused on the first common layer  430 , the leakage current blocking layer  440 , the light emitting layer  460 , the second common layer  570 , and the second electrode  590 . 
     The light emitting display device  500  according to still another embodiment of the present invention includes substrate  105 , a first electrode  110 , a pixel defining layer  120 , a first common layer  430 , a leakage current blocking layer  440 , a light emitting layer  460 , a second common layer  570 , and a second electrode  590 . These members are sequentially stacked in a Z direction of  FIG. 8 . 
     The first common layer  430 , the leakage current blocking layer  440 , and the light emitting layer  460  have been described in detail in the above described embodiment, and thus a redundant description thereof may not be provided. 
     The second common layer  570  may be disposed on the light emitting layer  460  to have a continuous form between the adjacent pixels PX. The second common layer  570  may be the electron transport layer  170  or the electron injection layer  180  illustrated in  FIG. 2 . That is, the electron injection layer  180  or the electron transport layer  170  illustrated in  FIG. 2  may be omitted in the light emitting display device  500 . The second common layer  570  may be formed by, for example, a deposition method, or any other suitable method. 
     The second common layer  570  may be applied to the light emitting display device  100  of  FIG. 2  instead of the electron transport layer  170  and the electron injection layer  180 , to the light emitting display device  200  of  FIG. 5  instead of the electron transport layer  270  and the electron injection layer  280 , or to the light emitting display device  600  of  FIG. 6  instead of the electron transport layer  170  and the electron injection layer  180 . 
     The second electrode  590  is similar to the second electrode  190  of  FIG. 2 . However, the second electrode  590  is disposed on the second common layer  570 . The second electrode  590  may have the same or substantially the same function as the second electrode  190  of  FIG. 2 . 
     As described above, the light emitting display device  500  according to still another embodiment of the present invention includes the leakage current blocking layer  440 , with a uniform thickness, disposed on the side surface of the pixel defining layer  120  between the first electrode  110  and the light emitting layer  460  at a region where a distance between the first electrode  110  and the second electrode  590  becomes smaller through the portion having a decreasing thickness in the light emitting layer  360 . This is because the light emitting layer  460  disposed in the opening OP of the pixel defining layer  120  has decreasing thickness at the portion corresponding to the side surface of the pixel defining layer  120 . 
     Accordingly, the light emitting display device  500  according to still another embodiment of the present invention may decrease the deterioration of light emission efficiency of the light emitting layer  460  by decreasing or preventing the occurrence of a leakage current between the first electrode  110  and the second electrode  590 , and thus the deterioration of display quality may be decreased. 
     Next, a light emitting display device  600  according to still another embodiment of the present invention will be described. 
       FIG. 9  is cross-sectional view of a light emitting display device according to still another embodiment of the present invention. 
     Referring to  FIG. 9 , the light emitting display device  400  according to still another embodiment of the present invention has the same or substantially the same configuration as the configuration of the light emitting display device  100  of  FIG. 1  except for a leakage current blocking layer  640 , an hole transport layer  650 , a light emitting layer  660 , and an electron transport layer  670 . Accordingly, explanation of the light emitting display device  600  according to still another embodiment of the present invention will be primarily focused on the leakage current blocking layer  640 , the hole transport layer  650 , the light emitting layer  660 , and the electron transport layer  670 . 
     The light emitting display device  600  according to still another embodiment of the present invention includes substrate  105 , a first electrode  110 , a pixel defining layer  120 , a hole injection layer  130 , a leakage current blocking layer  640 , a hole transport layer  650 , a light emitting layer  660 , an electron transport layer  670 , an electron injection layer  180 , and a second electrode  190 . These members are sequentially stacked in a Z direction of  FIG. 9 . 
     The leakage current blocking layer  640  is similar to the leakage current blocking layer  140  of  FIG. 2 . However, the leakage current blocking layer  640  is disposed on the side surface of the pixel defining layer  120  between the light emitting layer  660  and the second electrode  190 . For example, the leakage current blocking layer  640  may be disposed on a side portion of the light emitting layer  660  disposed on the side surface of the pixel defining layer  120 , between the light emitting layer  660  and the electron transport layer  670 . 
     Further, because the electron transport layer  670  is formed on the leakage current blocking layer  640  by a deposition method, it is not required that the leakage current blocking layer  640  has a lyophobic property. Accordingly, the leakage current blocking layer  640  may be formed of an insulating material having an electric resistance higher than an electric resistance of the light emitting layer  660  in order to prevent or substantially prevent a leakage current from flowing between the first electrode  110  and the second electrode  190 . Thus, the leakage current blocking layer  640  may be formed of an inorganic insulating material such as silicon Oxide, Silicon Nitride, silicon Oxynitride, and/or the like. In this case, the leakage current blocking layer  640  may be formed by a sputtering deposition method having a high straightness. The sputtering deposition method is a method of depositing a deposition material on a substrate, which applies impact to a surface of a target that is made of the deposition material by particles having energy and thus makes the deposition material secede and discharge from the surface of the target through momentum exchange at the time of the impact. Further, leakage current blocking layer  640  may be formed of an organic insulating material. The organic insulating material may be at least one polymer resin selected from the group including benzo cyclo butane (BCB), polyimide (PI), poly amaide (PA), acryl resin, phenol resin, and the like. In this case, the leakage current blocking layer  640  may be formed by an evaporation deposition method. 
     The leakage current blocking layer  640  may have the same or substantially the same function as the leakage current blocking layer  140  of  FIG. 2 . 
     The hole transport layer  650  is similar to the hole transport layer  150  of  FIG. 2 . However, the hole transport layer  650  is disposed between the hole injection layer  130  and the light emitting layer  660 . The hole transport layer  650  may have the same or substantially the same function as the hole transport layer  150  of  FIG. 2 . 
     The light emitting layer  660  is similar to the light emitting layer  160  of  FIG. 2 . However, the light emitting layer  660  is disposed on the hole transport layer  650  and the leakage current blocking layer  640  in the opening OP of the pixel defining layer  120 . The light emitting layer  660  may have the same or substantially the same function as the light emitting layer  160  of  FIG. 2 . 
     The electron transport layer  670  is similar to the electron transport layer  170  of  FIG. 2 . However, the electron transport layer  670  is disposed on the light emitting layer  660  and the leakage current blocking layer  640 . The electron transport layer  670  may have the same or substantially the same function as the electron transport layer  170  of  FIG. 2 . 
     As described above, the light emitting display device  600  according to still another embodiment of the present invention includes the leakage current blocking layer  640 , with a uniform thickness, disposed on the side surface of the pixel defining layer  120  between the light emitting layer  660  and the second electrode  190  at a region where a distance between the first electrode  110  and the second electrode  190  becomes smaller through the portion having a decreasing thickness in the light emitting layer  360 . This is because the light emitting layer  660  disposed in the opening OP of the pixel defining layer  120  has decreasing thickness at the portion corresponding to the side surface of the pixel defining layer  120 . 
     Accordingly, the light emitting display device  600  according to still another embodiment of the present invention may decrease the deterioration of light emission efficiency of the light emitting layer  660  by decreasing or preventing the occurrence of a leakage current between the first electrode  110  and the second electrode  190 , and thus the deterioration of display quality may be decreased. 
     The electron transport layer  270  and the electron injection layer  280  of  FIG. 5  may be applied to the light emitting display device  600  of  FIG. 9  instead of the electron transport layer  670  and the electron injection layer  180 , the first common layer  430  of  FIG. 7  may be applied to the light emitting display device  600  of  FIG. 9  in which the hole transport layer  650  is omitted instead of the hole injection layer  130 , the second common layer  570  of  FIG. 8  may be applied to the light emitting display device  600  of  FIG. 9  instead of the electron transport layer  670  and the electron injection layer  180 , or the first common layer  430  of  FIG. 7  may be applied to the light emitting display device  600   FIG. 9  in which the hole transport layer  650  is omitted instead of the hole injection layer  130  and the second common layer  570  of  FIG. 8  may be applied to the light emitting display device  600  of  FIG. 9  instead of the electron transport layer  670  and the electron injection layer  180 . 
     Next, an example method of manufacturing light emitting display devices according to various embodiments of the present invention will now be described. 
       FIGS. 10 through 20  are views illustrating a method of manufacturing a light emitting display device according to an embodiment of the present invention. 
     Referring to  FIG. 10 , a first electrode  110  is formed on a substrate  105  having a plurality of pixels for each of the plurality of pixels PX. The first electrode  110  may be formed by depositing a transparent electrode material or a reflective material on the substrate  105  and patterning the transparent electrode material or the reflective material. 
     Then, referring to  FIG. 11 , a pixel defining layer  120  is formed on the substrate  105  to partition each pixel PX and to have an opening OP that exposes the first electrode  110 . The pixel defining layer  120  may be formed by depositing an insulating material on the whole surface of the substrate  105  to cover the first electrode  110  using a deposition method and patterning the deposited insulating material. 
     The pixel defining layer  120  is formed to have a lyophobic property in order to prevent or substantially prevent a hole injection solution from going out the opening OP of the pixel defining layer  120  when forming the hole injection layer  130  by discharging the hole injection solution into the opening OP of the pixel defining layer  120  using an ink printing method, a nozzle printing method, or the like. For example, the pixel defining layer  120  may be formed of an insulating material that makes a contact angle of a hole injection solution against the pixel defining layer  120  become greater than or equal to about 40°. 
     Then, referring to  FIG. 12 , a hole injection layer  130  is formed on the first electrode  110 . The hole injection layer  130  may be disposed along the first electrode  110  and the side surface of the pixel defining layer  120  in the opening OP of the pixel defining layer  120 . The hole injection layer  130  may be formed by discharging a hole injection solution into the opening OP of the pixel defining layer  120  using an inkjet printing method, a nozzle printing method, or the like. In this case, the hole injection layer  130  may have a thickness decreasing toward the side surface of the pixel defining layer  120  from the first electrode  110 . 
     Then, referring to  FIGS. 13 through 17 , a leakage current blocking layer  140  is formed on the side surface (For example, the side portion of the hole injection layer  130  illustrated in  FIG. 12 ) and an upper surface of the pixel defining layer  120  in the opening OP of the pixel defining layer  120 . 
     For example, as illustrated in  FIG. 13 , a first mask  10  having first openings  10   a  is disposed on the substrate  105  including the hole injection layer  130  illustrated in  FIG. 12 . The first openings  10   a  are disposed to expose side portions of the hole injection layer  130  (see, e.g.,  FIG. 12 ) facing each other in the first direction X in the opening OP of the pixel defining layer  120 . In this case, the first openings  10   a  may be formed to extend along the second direction Y and have a continuous form between adjacent openings OP of the pixel defining layer  120  in the first direction X. 
     After the first mask  10  having the first openings  10   a  is disposed on the substrate  105  including the hole injection layer  130  illustrated in  FIG. 12 , a material forming (or a forming material of) the leakage current blocking layer  140  is deposited on the side portions of the hole injection layer  130  (see, e.g.,  FIG. 12 ) and on the upper surface of the pixel defining layer  120 , which are exposed through the first openings  10   a  of the first mask  10  using a deposition method such as evaporation deposition method. Then, as illustrated in  FIG. 14 , first blocking portions  140   a  are formed on the side portions of the hole injection layer  130  (see, e.g.,  FIG. 12 ) and on the upper surface of the pixel defining layer  120 , which are exposed through the first openings  10   a  of the first mask  10 . 
     After the first blocking portions  140   a  are formed, a second mask  20  having second openings  20   a  is disposed on the substrate  105  including the first blocking portions  140   a , as illustrated in  FIG. 15 . The second openings  20   a  are disposed to expose side portions of the hole injection layer  130  (see, e.g.,  FIG. 12 ) facing each other in the second direction Y in the opening OP of the pixel defining layer  120 . In this case, the second openings  20   a  may be formed to extend along the first direction X and have a continuous form between adjacent openings OP of the pixel defining layer  120  in the second direction Y. 
     After the second mask  20  having the second openings  20   a  is disposed on the substrate  105  including the first blocking portions  140   a , the material forming (or the forming material) of the leakage current blocking layer  140  is deposited on the side portions of the hole injection layer  130  (see, e.g.,  FIG. 12 ) and on the upper surface of the pixel defining layer  120 , which are exposed through the second openings  20   a  of the second mask  20  using a deposition method such as evaporation deposition method. Then, as illustrated in  FIG. 16 , second blocking portions  140   b  are formed on the side portions of the hole injection layer  130  (see, e.g.,  FIG. 12 ) and on the upper surface of the pixel defining layer  120 , which are exposed through the second openings  20   a  of the second mask  20 . 
     Then, referring to  FIG. 18 , a hole transport layer  150  is formed on the hole injection layer  130  and the leakage current blocking layer  140  in the opening OP of the pixel defining layer  120 . The hole transport layer  150  may be formed by discharging a hole transport solution into the opening OP of the pixel defining layer  120  using an inkjet printing method, a nozzle printing method, or the like. In this case, the hole transport layer  150  may have a thickness decreasing toward the side surface of the pixel defining layer  120  from the first electrode  110 . 
     Then, referring to  FIG. 19 , a light emitting layer  160  is formed on the hole transport layer  150  in the opening OP of the pixel defining layer  120 . The light emitting layer  160  may be formed by discharging a light emitting solution into the opening OP of the pixel defining layer  120  using an inkjet printing method, a nozzle printing method, or the like. In this case, the light emitting layer  160  may have a thickness decreasing toward the side surface of the pixel defining layer  120  from the first electrode  110 . For example, the light emitting layer  160  may include a first portion  160   a  located on the first electrode  110  and a second portion  160   b  located on the side surface of the pixel defining layer  120 . The first portion  160   a  may have a uniform thickness, and the second portion  160   b  may have a thickness decreasing in a direction toward the upper surface of the pixel defining layer from the side surface of the pixel defining layer  120 . 
     Then, referring to  FIG. 20 , an electron transport layer  170 , an electron injection layer  180 , and a second electrode  190  are formed on the light emitting layer  160 . The electron transport layer  170 , the electron injection layer  180 , and the second electrode  190  may be sequentially formed using a deposition method. 
     The method of manufacturing a light emitting display device according to the embodiment may further include disposing an encapsulation substrate on the second electrode  190 . In addition, the method of manufacturing a light emitting display device according to the embodiment may further include disposing a spacer between the second electrode  190  and the encapsulation substrate. Various suitable methods of placing the encapsulation substrate and placing the spacer are widely disclosed in the art to which the present invention pertains, and thus a detailed description thereof may not be provided. 
     In concluding the detailed description, those skilled in the art will appreciate that many variations and modifications may be made to the exemplary embodiments without substantially departing from the principles of the present invention. Therefore, the disclosed exemplary embodiments of the invention are used in a generic and descriptive sense, and not for purposes of limitation. Descriptions of features or aspects within each exemplary embodiment should typically be considered as available for other similar features or aspects in other exemplary embodiments. 
     While one or more exemplary embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various suitable changes in form and details may be made therein without departing from the spirit and scope as defined by the following claim, and equivalents thereof. 
     It will be understood that, although the terms “first”, “second”, “third”, etc., may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section, without departing from the spirit and scope of the inventive concept. 
     It will also be understood that when a layer is referred to as being “between” two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present. 
     The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting of the inventive concept. As used herein, the singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “include,” “including,” “comprises,” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. Further, the use of “may” when describing embodiments of the inventive concept refers to “one or more embodiments of the inventive concept.” Also, the term “exemplary” is intended to refer to an example or illustration. 
     It will be understood that when an element or layer is referred to as being “on” or “adjacent to” another element or layer, it can be directly on, connected to, coupled to, or adjacent to the other element or layer, or one or more intervening elements or layers may be present. 
     As used herein, the term “substantially,” “about,” and similar terms are used as terms of approximation and not as terms of degree, and are intended to account for the inherent variations in measured or calculated values that would be recognized by those of ordinary skill in the art. 
     As used herein, the terms “use,” “using,” and “used” may be considered synonymous with the terms “utilize,” “utilizing,” and “utilized,” respectively.