Display device

Abstract

A display device according to one embodiment includes a first electrode, an organic layer disposed on the first electrode, and a second electrode covering the organic layer. The organic layer includes a first layer having a first end portion and a second layer between the first layer and the second electrode. The second layer covers the first end portion.

Description

[0001] Cross-reference to related applications

[0002] This application is based on and claims the benefit of priority from Japanese Patent Application No. 2021-008990 filed on January 22, 2021, and incorporates by reference all of the contents described in the Japanese Patent Application. Technical Field

[0003] An embodiment of the present invention relates to a display device. Background Art

[0004] In recent years, display devices using organic light emitting diodes (OLEDs) as display elements have been put into practical use. The display element includes a pair of electrodes and an organic layer disposed between the electrodes. The organic layer is formed by, for example, vacuum evaporation.

[0005] For example, when an organic layer is formed by stacking a plurality of functional layers, there is a risk that the ends of the functional layers may be uneven at the periphery of the organic layer, which may lead to deterioration in the performance of the display element. Summary of the invention

[0006] According to one embodiment, a display device includes a first electrode, an organic layer disposed on the first electrode, and a second electrode covering the organic layer. The organic layer includes a first layer having a first end portion, and a second layer between the first layer and the second electrode. The second layer covers the first end portion.

[0007] According to another embodiment, a display device includes: a first electrode; a rib having an opening overlapping with the first electrode and covering a peripheral portion of the first electrode; an organic layer in contact with the first electrode through the opening, with an end portion located on the rib; and a second electrode covering the organic layer. At least one of the plurality of layers constituting the organic layer overlaps with the opening and includes a first region where a dopant is distributed at a first concentration, and a second region located on the rib where the dopant is distributed at a second concentration lower than the first concentration.

[0008] According to these structures, it is possible to provide a display device capable of suppressing the performance degradation of a display element. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a diagram showing a configuration example of a display device according to the first embodiment.

[0010] Figure 2 This is a diagram showing an example of the layout of sub-pixels according to the first embodiment.

[0011] Figure 3 It is along Figure 2A schematic cross-sectional view of a display device taken along line III-III in FIG.

[0012] Figure 4 This is a cross-sectional view showing an example of a layer structure that can be applied to the organic layer according to the first embodiment.

[0013] Figure 5 It is a schematic plan view of an organic layer according to the first embodiment.

[0014] Figure 6 It is along Figure 5 A schematic cross-sectional view of the display device taken along line VI-VI in FIG.

[0015] Figure 7 This is a diagram schematically showing an example of a method for forming an organic layer according to the first embodiment.

[0016] Figure 8 It is a diagram showing examples of parameters related to vapor deposition.

[0017] Fig. 9 This is a diagram schematically showing another example of the method for forming the organic layer according to the first embodiment.

[0018] Fig.10 It is a cross-sectional view schematically showing the structure of a display device according to a comparative example.

[0019] Fig.11 This is a schematic cross-sectional view showing an enlarged view of the vicinity of an end portion of the organic layer according to the first embodiment.

[0020] Fig.12 Yes means Fig.11 A diagram showing the energy levels of the layers in the first path A1-A2.

[0021] Fig.13 Yes means Fig.11 A diagram showing the energy levels of the layers in the second path B1-B2.

[0022] Fig.14 Yes means Fig.11 A diagram showing the energy levels of the layers in the third path C1-C2.

[0023] Fig.15 It is a schematic plan view of an organic layer according to the second embodiment.

[0024] Fig.16 It is along Fig.15 Schematic cross-sectional view of the display device taken along line XVI-XVI in FIG.

[0025] Fig.17 It is a schematic cross-sectional view of a display device according to a third embodiment.

[0026] Fig.18 It is a schematic cross-sectional view of a display device according to a fourth embodiment.

[0027] Fig.19 It is a schematic cross-sectional view of a display device according to a fifth embodiment.

[0028] Fig. 20 It is a schematic cross-sectional view of a display device according to a sixth embodiment.

[0029] Fig.21 It is a schematic cross-sectional view of a display device according to the seventh embodiment.

[0030] Fig. 22 This is a diagram schematically showing an example of a method for forming an organic layer according to the seventh embodiment.

[0031] Fig.23 This is a diagram showing an example of a sub-pixel and an organic layer according to the eighth embodiment.

[0032] Fig.24 This is a diagram for explaining an example of the effect of the eighth embodiment.

[0033] Fig.25 It is a schematic cross-sectional view of a display device according to a ninth embodiment.

[0034] Fig.26 It is a diagram showing the energy level of each layer included in the organic layer according to the ninth embodiment.

[0035] Fig. 27 It is a schematic cross-sectional view of a display device according to a tenth embodiment.

[0036] Fig.28 It is a schematic plan view of a first carrier injection layer according to the tenth embodiment.

[0037] Fig.29 This is a diagram showing an example of a method for forming a first carrier injection layer according to the tenth embodiment.

[0038] Fig.30 It is a plan view showing another example of the first region and the second region according to the tenth embodiment. DETAILED DESCRIPTION

[0039] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0040] In addition, the disclosed content is only an example after all, and the appropriate changes that can be easily thought of by those skilled in the art based on the main idea of ​​the invention are of course included in the scope of the present invention. In addition, the drawings are for the purpose of more clear explanation, and there are cases where the width, thickness, shape, etc. of each part are schematically shown compared with the actual form, but after all, it is an example and does not limit the interpretation of the present invention. In addition, in this specification and each drawing, the same reference numerals are marked for the components that perform the same or similar functions as those described in the previous drawings, and sometimes repeated detailed descriptions are appropriately omitted.

[0041] In addition, in the drawings, mutually orthogonal X-axis, Y-axis, and Z-axis are described as needed for easy understanding. The direction along the X-axis is called the first direction, the direction along the Y-axis is called the second direction, and the direction along the Z-axis is called the third direction. The plane defined by the X-axis and the Y-axis is called the XY plane, and the plane defined by the X-axis and the Z-axis is called the XZ plane. Observing the XY plane is called a top view.

[0042] The display device DSP according to the present embodiment is an organic electroluminescent display device having an organic light emitting diode (OLED) as a display element, and can be mounted on a television, a personal computer, an in-vehicle device, a tablet terminal, a smartphone, a mobile phone terminal, and the like.

[0043] [First embodiment]

[0044] Figure 1 1 is a diagram showing a configuration example of a display device DSP according to the first embodiment. The display device DSP has a display area DA for displaying an image and a peripheral area SA outside the display area DA on an insulating substrate 10. The substrate 10 may be glass or a flexible resin film.

[0045] The display area DA includes a plurality of pixels PX arranged in a matrix along the first direction X and the second direction Y. The pixel PX includes a plurality of sub-pixels SP. In one example, the pixel PX includes a red sub-pixel SP1, a green sub-pixel SP2, and a blue sub-pixel SP3. In addition, the pixel PX may include four or more sub-pixels in addition to sub-pixels of other colors such as white in addition to the sub-pixels of the above three colors.

[0046] The sub-pixel SP includes a pixel circuit 1 and a display element 20 driven by the pixel circuit 1. The pixel circuit 1 includes a pixel switch 2, a driving transistor 3, and a capacitor 4. The pixel switch 2 and the driving transistor 3 are switching elements composed of, for example, thin film transistors.

[0047] In the pixel switch 2, the gate electrode is connected to the scanning line GL. One of the source electrode and the drain electrode of the pixel switch 2 is connected to the signal line SL, and the other is connected to the gate electrode of the driving transistor 3 and the capacitor 4. In the driving transistor 3, one of the source electrode and the drain electrode is connected to the power line PL and the capacitor 4, and the other is connected to the anode of the display element 20. In addition, the structure of the pixel circuit 1 is not limited to the example shown in the figure.

[0048] The display element 20 is an organic light emitting diode (OLED) as a light emitting element. For example, the sub-pixel SP1 includes a display element that emits light corresponding to a red wavelength, the sub-pixel SP2 includes a display element that emits light corresponding to a green wavelength, and the sub-pixel SP3 includes a display element that emits light corresponding to a blue wavelength. The structure of the display element 20 will be described later.

[0049] Figure 2 is a diagram showing an example of the layout of sub-pixels SP1, SP2, and SP3. Here, four pixels PX are focused on. In each pixel PX, sub-pixels SP1, SP2, and SP3 are sequentially arranged along the first direction X. That is, in the display area DA, a column consisting of a plurality of sub-pixels SP1 arranged along the second direction Y, a column consisting of a plurality of sub-pixels SP2 arranged along the second direction Y, and a column consisting of a plurality of sub-pixels SP3 arranged along the second direction Y are alternately arranged in the first direction X.

[0050] The ribs 14 are arranged at the boundaries between the sub-pixels SP1, SP2, and SP3. Figure 2 In the example of FIG. 1 , the ribs 14 are in a grid shape and have portions located between sub-pixels adjacent to each other in the first direction X and portions located between sub-pixels adjacent to each other in the second direction Y. The ribs 14 form openings OP in the sub-pixels SP1 , SP2 , and SP3 .

[0051] in addition, Figure 2 The outer shapes of the sub-pixels SP1 , SP2 , and SP3 shown correspond to, for example, the outer shape of the light-emitting region of the display element 20 , but are simplified and do not necessarily reflect the actual shapes.

[0052] Figure 3 It is along Figure 2 A schematic cross-sectional view of a display device DSP along line III-III. Figure 3 In FIG. 1 , as elements provided in each of the sub-pixels SP1 , SP2 , and SP3 , the driving transistor 3 and the display element 20 are shown, and illustration of other elements is omitted.

[0053] The display device DSP includes the above-mentioned substrate 10, insulating layers 11, 12, 13, the above-mentioned ribs 14, and a sealing layer 15. The insulating layers 11, 12, 13 are stacked on the substrate 10 along the third direction Z. For example, the insulating layers 11 and 12 are formed of an inorganic material, and the insulating layer 13, the ribs 14, and the sealing layer 15 are formed of an organic material.

[0054] The driving transistor 3 includes a semiconductor layer 30 and electrodes 31, 32, and 33. The electrode 31 corresponds to a gate electrode. One of the electrodes 32 and 33 corresponds to a source electrode, and the other corresponds to a drain electrode. The semiconductor layer 30 is arranged between the substrate 10 and the insulating layer 11. The electrode 31 is arranged between the insulating layers 11 and 12. The electrodes 32 and 33 are arranged between the insulating layers 12 and 13, and are in contact with the semiconductor layer 30 through contact holes penetrating the insulating layers 11 and 12.

[0055] The display element 20 includes a first electrode E1, an organic layer OR, and a second electrode E2. The first electrode E1 is an electrode disposed for each sub-pixel SP or each display element 20, and is sometimes referred to as a pixel electrode, a lower electrode, or an anode. The second electrode E2 is an electrode disposed in common with respect to a plurality of sub-pixels SP or a plurality of display elements 20, and is sometimes referred to as a common electrode, an upper electrode, or a cathode.

[0056] The rib 14 is arranged on the insulating layer 13. The first electrode E1 is arranged on the insulating layer 13 and overlaps with the opening OP. The peripheral portion of the first electrode E1 is covered by the rib 14. The first electrode E1 is electrically connected to the electrode 33 through the contact hole CH that penetrates the insulating layer 13. For example, the first electrode E1 is formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The first electrode E1 may also be a metal electrode (reflective electrode) formed of a metal material such as silver or aluminum. In addition, the first electrode E1 may also be a stack of a transparent electrode and a metal electrode. For example, the first electrode E1 may also be a stack formed by stacking a transparent electrode, a metal electrode, and a transparent electrode in this order, or may be a stack of more than three layers.

[0057] The organic layer OR is disposed on the rib 14 and contacts the first electrode E1 through the opening OP. The peripheral edge of the organic layer OR is located on the rib 14 .

[0058] The second electrode E2 covers the organic layer OR. Figure 3 In the example of FIG. 1 , the second electrode E2 is continuously provided across the sub-pixels SP1, SP2, and SP3. The second electrode E2 is formed of, for example, a transparent conductive material such as ITO or IZO. The sealing layer 15 is disposed on the second electrode E2. The sealing layer 15 is, for example, formed to be thicker than the insulating layers 11, 12, 13 and the ribs 14, and protects the organic layer OR from moisture and the like, and flattens the unevenness generated by the ribs 14.

[0059] Figure 4 1 is a cross-sectional view showing an example of a layer structure that can be applied to the organic layer OR. For example, the organic layer OR includes a first carrier injection layer 51, a first carrier transport layer 52, a first carrier blocking layer 53, a light emitting layer 54 (EML), a second carrier blocking layer 55, a second carrier transport layer 56, and a second carrier injection layer 57 stacked in sequence from the first electrode E1 to the second electrode E2.

[0060] In this embodiment, it is assumed that the first electrode E1 is an anode and the second electrode E2 is a cathode. For example, in this case, the first carrier injection layer 51 is a hole injection layer (HIL) that generates holes, the first carrier transport layer 52 is a hole transport layer (HTL) that transports holes toward the light-emitting layer 54, the first carrier blocking layer 53 is an electron blocking layer (EBL) that shields the movement of electrons, the second carrier blocking layer 55 is a hole blocking layer (HBL) that shields the movement of holes, the second carrier transport layer 56 is an electron transport layer (ETL) that transports electrons toward the light-emitting layer 54, and the second carrier injection layer 57 is an electron injection layer (EIL) that generates electrons.

[0061] Figure 5 It is a schematic top view of the organic layer OR. Figure 6 It is along Figure 5 A schematic cross-sectional view of the display device DSP taken along line VI-VI in FIG. Figure 5 In FIG. 1 , the shape of the organic layer OR in a plan view is shown in a region to the left of the center line CL in the first direction X of the sub-pixel SP (display element 20 ), and the outer shapes of the layers 51 to 57 of the organic layer OR and the opening OP are shown in a region to the right of the center line CL.

[0062] The first carrier injection layer 51 has an end S1, the first carrier transport layer 52 has an end S2, the first carrier blocking layer 53 has an end S3, the light emitting layer 54 has an end S4, the second carrier blocking layer 55 has an end S5, the second carrier transport layer 56 has an end S6, and the second carrier injection layer 57 has an end S7. The ends S1 to S7 may also be referred to as edges, peripheries, or outer shapes, for example. Figure 5 In the example of FIG. 1 , for the sake of simplicity of illustration, the ends S1 and S2 are represented by a single line. Similarly, the ends S6 and S7 are also represented by a single line.

[0063] exist Figure 5 In the example of FIG. 5 , each of the layers 51 to 57 and the opening OP is rectangular. That is, the ends S1 to S7 and the opening OP have two sides parallel to the first direction X and two sides parallel to the second direction Y, respectively.

[0064] In a plan view, ends S1 and S2 are located between ends S4 and S5, end S4 is located between ends S1 and S2 and ends S6 and S7, end S5 is located between ends S1 and S2 and end S3, and ends S6 and S7 are located between end S4 and opening OP. End S3 corresponds to the outermost periphery of the organic layer OR.

[0065] From another point of view, the area of ​​the second carrier blocking layer 55 is larger than the areas of the first carrier injection layer 51, the first carrier transport layer 52, the light emitting layer 54, the second carrier transport layer 56, and the second carrier injection layer 57. Moreover, the area of ​​the first carrier blocking layer 53 is larger than the area of ​​the second carrier blocking layer 55.

[0066] like Figure 6 As shown, the ends S1 to S7 are all located on the rib 14 . The first carrier injection layer 51 contacts the first electrode E1 through the opening OP. The first carrier transport layer 52 is entirely located on the first carrier injection layer 51 .

[0067] Most of the first carrier blocking layer 53 is located on the first carrier transporting layer 52, and a portion near the end S3 is in contact with the rib 14. That is, the first carrier blocking layer 53 covers the end S1 of the first carrier injection layer 51 and the end S2 of the first carrier transporting layer 52.

[0068] The entire light emitting layer 54 is located on the first carrier blocking layer 53. Most of the second carrier blocking layer 55 is located on the light emitting layer 54, and a portion near the end S5 is in contact with the first carrier blocking layer 53. That is, the second carrier blocking layer 55 covers the end S4 of the light emitting layer 54.

[0069] The second carrier transport layer 56 is entirely located on the second carrier blocking layer 55. The second carrier injection layer 57 is entirely located on the second carrier transport layer 56.

[0070] The end portions S1 and S2 are covered by the first carrier blocking layer 53 and are not in contact with the second electrode E2. In addition, the end portion S4 is covered by the second carrier blocking layer 55 and is not in contact with the second electrode E2.

[0071] The end S3 of the first carrier blocking layer 53 and its vicinity are in contact with the second electrode E2. The end S5 of the second carrier blocking layer 55 and its vicinity are in contact with the second electrode E2.

[0072] The end S6 is in contact with the second electrode E2. The second carrier injection layer 57 is in contact with the second electrode E2 at the upper surface and the end S7. Figure 6 , a cross section on an XZ plane defined by the first direction X and the third direction Z is shown, but a cross section on a YZ plane defined by the second direction Y and the third direction Z also has the same structure.

[0073] Next, an example of a method for manufacturing the display device DSP will be described with attention paid to a step of forming the organic layer OR. Each layer constituting the organic layer OR can be formed by vacuum deposition using a point deposition source, for example.

[0074] Figure 7 1 is a diagram schematically showing an example of a method for forming an organic layer OR. The method includes a first step P11 and a second step P12. Layers having a relatively small area in the organic layer OR, such as the first carrier injection layer 51, the first carrier transport layer 52, the light emitting layer 54, the second carrier transport layer 56, and the second carrier injection layer 57, are formed by the first step P11. Layers having a relatively large area in the organic layer OR, such as the first carrier blocking layer 53 and the second carrier blocking layer 55, are formed by the second step P12.

[0075] In each of the first step P11 and the second step P12, a mask MSK having an opening corresponding to the organic layer OR is arranged for the substrate SUB having a portion of the display device DSP formed with a layer lower than the organic layer OR. The mask MSK used in the first step P11 and the second step P12 is the same. In the first step P11, the substrate SUB moves relative to the evaporation source DS1 arranged below the mask MSK at a speed V1. In the second step P12, the substrate SUB moves relative to the evaporation source DS2 arranged below the mask MSK at a speed V2.

[0076] In the second step P12, the range of molecules from the evaporation source DS2 reaching the substrate SUB through the openings of the mask MSK is larger than the range of molecules from the evaporation source DS1 reaching the substrate SUB through the openings of the mask MSK in the first step P11. As a result, an area difference ΔS is generated between the layers formed in the first step P11 and the second step P12. The first step P11 can also be called narrow-angle evaporation, and the second step P12 can be called wide-angle evaporation.

[0077] The first step P11 and the second step P12 that generate such an area difference ΔS can be realized by adjusting various parameters related to vapor deposition. As an example of the parameters, for example, the distance d1 between the substrate SUB and the vapor deposition sources DS1 and DS2, the distance d2 between the substrate SUB and the mask MSK, the size of the holes provided in the vapor deposition sources DS1 and DS2, the speeds V1 and V2, the angle θ of the vapor deposition sources relative to the vertical direction of the substrate SUB, the number of vapor deposition sources DS1 and DS2, the density of the vapor deposition sources DS1 and DS2, etc. can be cited.

[0078] Figure 8Figures showing other examples (a), (b), and (c) of the above parameters. In examples (a), (b), and (c), three vapor deposition sources DS are shown, and the angles of these vapor deposition sources DS are different. In example (a), the three vapor deposition sources DS are parallel to each other. In example (b), each vapor deposition source DS is tilted in such a way that the distance between the vapor deposition sources DS on the front end side of the released molecules becomes larger. In example (c), each vapor deposition source DS is tilted in such a way that the distance between the vapor deposition sources DS on the front end side of the released molecules becomes smaller.

[0079] In the first step P11 and the second step P12, the configuration of the vapor deposition sources DS1 and DS2 may be changed as in the vapor deposition source DS of examples (a), (b), and (c). For example, by applying example (c) to the vapor deposition source DS1 in the first step P11 and applying one of examples (a) and (b) to the vapor deposition source DS2 in the second step P12, an area difference ΔS can be generated.

[0080] Fig. 9 1 is a diagram schematically showing another example of a method for forming an organic layer OR. The method includes a first step P21 and a second step P22. Layers having a relatively small area in the organic layer OR, such as the first carrier injection layer 51, the first carrier transport layer 52, the light emitting layer 54, the second carrier transport layer 56, and the second carrier injection layer 57, are formed by the first step P21. Layers having a relatively large area in the organic layer OR, such as the first carrier blocking layer 53 and the second carrier blocking layer 55, are formed by the second step P22.

[0081] In the first step P21, a mask MSK1 having an opening corresponding to the organic layer OR is used. In the second step P22, a mask MSK2 having an opening larger than the opening of the mask MSK1 is used. Fig. 9 The evaporation source is omitted.

[0082] Due to the size difference between the openings of the masks MSK1 and MSK2, in the second step P22, molecules from the vapor deposition source reach a larger area of ​​the substrate SUB than in the first step P21. As a result, an area difference ΔS occurs between the layers formed in the first step P11 and the second step P12.

[0083] According to Figure 7 as well as Fig. 9 The formation methods described in the above are all capable of forming a layer having an area difference ΔS. Figure 7 In the formation method of, three or more layers having area differences can be formed through three or more steps with different parameters related to vapor deposition. Fig. 9In the formation method of, even in the case of three or more steps using masks with different opening sizes, three or more layers having different areas can be formed. By appropriately using this method, it is possible to form Figure 5 as well as Figure 6 The organic layer OR is shown.

[0084] Next, an example of the effect achieved by this embodiment will be described.

[0085] Fig.10 1 is a cross-sectional view schematically showing the structure of a display device DSPa according to a comparative example. Figure 6 The cross section of the same sub-pixel SP (display element 20). Fig.10 In, with Figure 6 The same or similar elements are denoted by the same reference numerals.

[0086] In the display device DSPa, the layers 51 to 57 constituting the organic layer OR are smaller as they are located at the top. As a result, the ends S1 to S7 are in contact with the second electrode E2, respectively. Therefore, unlike the original path of the current that passes through the layers 51 to 57 in sequence between the first electrode E1 and the second electrode E2, a leakage path can be formed that reaches the second electrode E2 from the first electrode E1 through a part of the layers 51 to 57. The leakage path causes an increase in power consumption due to off-state leakage current or leakage current, and a decrease in the driving performance of the display element 20.

[0087] In particular, when the layers 51 to 57 of the organic layer OR are formed using a single mask, the materials of each layer are also accumulated at the edge of the opening of the mask, so the later the layer is formed, the smaller the area. Fig.10 The end portions S1 to S7 shown are respectively in contact with the second electrode E2.

[0088] Fig.11 1 is a schematic cross-sectional view of the enlarged vicinity of the end of the organic layer OR in the display device DSP according to the present embodiment. As described above, in the present embodiment, the ends S1 and S2 of the first carrier injection layer 51 and the first carrier transport layer 52 are covered by the first carrier blocking layer 53. In addition, the end S4 of the light emitting layer 54 is covered by the second carrier blocking layer 55.

[0089] Here, we focus on Fig.11The first path A1-A2, the second path B1-B2 and the third path C1-C2 in the embodiment. The first path A1-A2 passes through the first electrode E1, the layers 51 to 57 and the second electrode E2. The second path B1-B2 passes through the first electrode E1, the first carrier injection layer 51, the first carrier blocking layer 53, the second carrier blocking layer 55 and the second electrode E2. The third path C1-C2 passes through the first electrode E1, the first carrier injection layer 51, the first carrier blocking layer 53 and the second electrode E2.

[0090] Fig.12 : is a diagram showing the energy level of each layer in the first path A1 - A2 . Fig.13 : is a diagram showing the energy level of each layer in the second path B1 - B2 . Fig.14 is a diagram showing the energy level of each layer in the third path C1 - C2 .

[0091] like Fig.12 As shown, in the first path A1-A2, electrons are shielded by the first carrier blocking layer 53, and holes are shielded by the second carrier blocking layer 55. Fig.13 In the second path B1-B2 shown, electrons are shielded by the first carrier blocking layer 53, and holes are shielded by the second carrier blocking layer 55. Therefore, leakage current is suppressed in the second path B1-B2.

[0092] On the other hand, Fig.14 In the third path C1-C2 shown, electrons are shielded by the first carrier blocking layer 53, but holes can flow through the second electrode E2. Even in this case, at least the electrons are shielded, thereby suppressing the leakage current. In addition, in the third path C1-C2, the first carrier transport layer 52 is not included, and acts as an energy barrier.

[0093] Not limited to the first path A1-A2, the second path B1-B2, and the third path C1-C2, in this embodiment, in any path passing through the first electrode E1, the organic layer OR, and the second electrode E2, at least one of the first carrier blocking layer 53 having a shallow lowest unoccupied molecular level (LUMO) and the second carrier blocking layer 55 having a deep highest occupied molecular orbital level (HOMO) exists. Thus, an effective leakage countermeasure can be achieved.

[0094] In addition to the above, various preferable effects can be obtained by this embodiment.

[0095] The following discloses the second to tenth embodiments as other examples to which the display device DSP can be applied. For structures not mentioned in each embodiment, the same structure as the first embodiment can be applied. Elements that are the same as or similar to those disclosed in the first embodiment are marked with the same reference numerals, and their description is sometimes omitted.

[0096] [Second embodiment]

[0097] Fig.15 It is a schematic plan view of the organic layer OR according to the second embodiment. Fig.16 It is along Fig.15 A schematic cross-sectional view of the display device DSP taken along line XVI-XVI in FIG. Fig.15 In, with Figure 5 Similarly, the shape of the organic layer OR in a plan view is shown in a region to the left of the center line CL in the first direction X of the sub-pixel SP (display element 20 ), and the outer shapes of the layers 51 to 57 of the organic layer OR and the opening OP are shown in a region to the right of the center line CL.

[0098] Fig.15 The organic layer OR shown Figure 5 The difference of the organic layer OR shown is that the area of ​​the second carrier blocking layer 55 is larger than the area of ​​the first carrier blocking layer 53. In a plan view, the ends S1 and S2 are located between the ends S3 and S4, the end S3 is located between the ends S1 and S2 and the end S5, the end S4 is located between the ends S1 and S2 and the ends S6 and S7, and the ends S6 and S7 are located between the end S4 and the opening OP. The end S5 corresponds to the outermost periphery of the organic layer OR.

[0099] like Fig.16 As shown, the second carrier blocking layer 55 is mostly located on the light-emitting layer 54, and the portion near the end S5 is in contact with the first carrier blocking layer 53 and the rib 14. That is, the second carrier blocking layer 55 covers the end S4 of the light-emitting layer 54 and the end S3 of the first carrier blocking layer 53. The ends S1 to S4 are not in contact with the second electrode E2. The end S5 and the portion near the end S5 of the second carrier blocking layer 55 are in contact with the second electrode E2. Fig.16 , the cross section on the XZ plane is shown, but the cross section on the YZ plane also has the same structure. When forming the organic layer OR, for example, the formation method disclosed in the first embodiment can be appropriately used.

[0100] According to the structure of this embodiment, the path between the first electrode E1 and the second electrode E2 passes through the first carrier blocking layer 53 and the second carrier blocking layer 55 at any position of the organic layer OR. Therefore, leakage current can be suppressed more effectively.

[0101] [Third Embodiment]

[0102] Fig.17 FIG. 1 is a schematic cross-sectional view of a display device DSP according to a third embodiment. Fig.17 In the example of , the first carrier transport layer 52 covers the end S1 of the first carrier injection layer 51, the first carrier blocking layer 53 covers the end S2 of the first carrier transport layer 52, the light emitting layer 54 covers the end S3 of the first carrier blocking layer 53, the second carrier blocking layer 55 covers the end S4 of the light emitting layer 54, the second carrier transport layer 56 covers the end S5 of the second carrier blocking layer 55, and the second carrier injection layer 57 covers the end S6 of the second carrier transport layer 56. In each layer 51 to 57, the portion near the end S1 to S7 is in contact with the rib 14. The second carrier injection layer 57 is in contact with the second electrode E2 as a whole, but the other layers 51 to 56 are not in contact with the second electrode E2.

[0103] exist Fig.17 , but the cross section on the YZ plane also has the same structure. That is, the area of ​​each layer 51 to 57 is larger as the layer is closer to the second electrode E2. When forming the organic layer OR, for example, the formation method disclosed in the first embodiment can be appropriately used.

[0104] According to the structure of this embodiment, the second carrier injection layer 57 is in contact with the second electrode E2, and the other layers 51 to 56 are not in contact with the second electrode E2. In addition, the path between the first electrode E1 and the second electrode E2 passes through the layers 51 to 57 at any position of the organic layer OR. This can more effectively suppress leakage current.

[0105] The second carrier injection layer 57 is located on the uppermost layer in the organic layer OR. Therefore, when the second carrier injection layer 57 is expanded as in the present embodiment, the end portions S1 to S6 of the other layers 51 to 56 can be entirely covered.

[0106] In addition, the ends S1 to S6 may also be Figure 6 or Fig.16 Even in this case, at least the second carrier injection layer 57 is interposed between the end portions S1 to S6 and the second electrode E2, so the effect of suppressing leakage current can be expected.

[0107] [Fourth Embodiment]

[0108] Fig.18 FIG. 1 is a schematic cross-sectional view of a display device DSP according to a fourth embodiment. Fig.18In the example of FIG. 5 , the first carrier transport layer 52 covers the end S1 of the first carrier injection layer 51. Thus, the first carrier injection layer 51 is not in contact with the second electrode E2.

[0109] On the other hand, end S2 of the first carrier transport layer 52, end S3 of the first carrier blocking layer 53, end S4 of the light emitting layer 54, end S5 of the second carrier blocking layer 55 and end S6 of the second carrier transport layer 56 are in contact with the second electrode E2.

[0110] exist Fig.18 , but the cross section on the YZ plane has the same structure. That is, the area of ​​the first carrier transport layer 52 is larger than the areas of the other layers 51 to 57. When forming the organic layer OR, for example, the formation method disclosed in the first embodiment can be appropriately used.

[0111] In this embodiment, the first electrode E1 is a reflective electrode that reflects light emitted by the light emitting layer 54. In addition, the first carrier transport layer 52 also has a function as an optical adjustment layer. Specifically, in order to adjust the relationship between the wavelength of light emitted from the light emitting layer 54 and the wavelength of light reflected by the first electrode E1 and directed upward, the first carrier transport layer 52 has a thickness T greater than that of the other layers 51, 53 to 57.

[0112] According to such a structure, the path between the first electrode E1 and the second electrode E2 passes through the thick first carrier transport layer 52 at any position of the organic layer OR. Thus, leakage current can be effectively suppressed.

[0113] [Fifth Embodiment]

[0114] Fig.19 FIG. 1 is a schematic cross-sectional view of a display device DSP according to a fifth embodiment. Fig.19 In the example of , the second carrier transport layer 56 covers the end S1 of the first carrier injection layer 51, the end S2 of the first carrier transport layer 52, the end S3 of the first carrier blocking layer 53, the end S4 of the light emitting layer 54, and the end S5 of the second carrier blocking layer 55. The end S6 of the second carrier transport layer 56 is not covered by the second carrier injection layer 57. In the second carrier transport layer 56, the end S6 and the vicinity thereof are in contact with the rib 14 and the second electrode E2. The layers 51 to 55 below the second carrier transport layer 56 are not in contact with the second electrode E2.

[0115] exist Fig.19, but the cross section in the YZ plane has the same structure. That is, the area of ​​the second carrier transport layer 56 is larger than the areas of the other layers 51 to 55 and 57. When forming the organic layer OR, for example, the formation method disclosed in the first embodiment can be appropriately used.

[0116] A thin film of a metal compound is generally used as the second carrier injection layer 57. Therefore, when the second carrier injection layer 57 located at the top of the organic layer OR is expanded, the ends S1 to S6 of the other layers 51 to 56 may not be well covered. On the other hand, the second carrier transport layer 56 is formed of an inorganic material or an organic material and is thicker than the second carrier injection layer 57. Therefore, the second carrier transport layer 56 is suitable for covering the ends S1 to S5.

[0117] [Sixth Embodiment]

[0118] In the first to fifth embodiments, the ends S1 to S7 of the layers 51 to 57 are assumed to have the same relationship along the entire periphery of the outer shape of the organic layer OR. However, the relationship between the ends S1 to S7 in a part of the outer shape of the organic layer OR may be different from the relationship between the ends S1 to S7 in other parts.

[0119] Fig. 20 This is a schematic cross-sectional view of a display device DSP according to the sixth embodiment, showing an example of a structure in which the relationship between the ends S1 to S7 is partially different in the outer shape of the organic layer OR. The end S1 has a first side S1a and a second side S1b. The end S2 has a first side S2a and a second side S2b. The end S3 has a first side S3a and a second side S3b. The end S4 has a first side S4a and a second side S4b. The end S5 has a first side S5a and a second side S5b. The end S6 has a first side S6a and a second side S6b. The end S7 has a first side S7a and a second side S7b. These sides are parallel to the second direction Y.

[0120] exist Fig. 20 In the example, the first sides S1a to S7a have Figure 6 The second sides S1b to S7b have the same relationship as the ends S1 to S7 shown in FIG. Fig.16 The first side S3a is not covered by the second carrier blocking layer 55. The second side S3b is covered by the second carrier blocking layer 55. The present invention is not limited to this example, and the relationship illustrated in each embodiment can be selectively applied to the first side S1a to S7a and the second side S1b to S7b.

[0121] exist Fig. 20, the cross section on the XZ plane is shown, but the same structure can be applied to the cross section on the YZ plane. That is, the relationship exemplified in each embodiment can be selectively applied to each of the pair of sides parallel to the first direction X in the end portions S1 to S7.

[0122] [Seventh Embodiment]

[0123] In the first to sixth embodiments, a structure is exemplified in which the layers 51 to 57 constituting the organic layer OR, except for the first carrier injection layer 51 located at the bottom, are expanded to cover the end of the layer below the expanded layer. In this embodiment, the structure of the organic layer OR and its formation method are exemplified from the viewpoint of reducing a specific layer to suppress the contact between the layer and the second electrode E2.

[0124] Fig.21 FIG. 1 is a schematic cross-sectional view of a display device DSP according to a seventh embodiment. Fig.21 In the example of , the light emitting layer 54 is smaller than the other layers 51 to 53 and 55 to 57. The end S4 of the light emitting layer 54 is covered by the second carrier blocking layer 55 and is not in contact with the second electrode E2. The ends S1 to S3 and S5 to S7 of the other layers 51 to 53 and 55 to 57 are in contact with the second electrode E2.

[0125] Fig. 22 1 is a diagram schematically showing an example of a method for forming an organic layer OR. In this method, for a substrate SUB having a portion of a lower layer than the organic layer OR formed in a display device DSP, each layer 51 to 57 is formed using a polymer mask PMSK and a metal mask MMSK. The polymer mask PMSK is disposed on a base layer BL formed on the substrate SUB and has an opening corresponding to the organic layer OR. The metal mask MMSK has an opening smaller than the opening of the polymer mask PMSK, and there is an area difference ΔS between the openings of the two masks.

[0126] The first carrier injection layer 51, the first carrier transport layer 52, and the first carrier blocking layer 53 below the light-emitting layer 54 are formed by evaporation through the opening of the polymer mask PMSK without the metal mask MMSK. Next, the metal mask MMSK is arranged on the polymer mask PMSK. The light-emitting layer 54 is formed by evaporation through the opening of the mask MMSK. Thereafter, the metal mask MMSK is removed. The second carrier blocking layer 55, the second carrier transport layer 56, and the second carrier injection layer 57 above the light-emitting layer 54 are formed by evaporation through the opening of the polymer mask PMSK. If each layer 51 to 57 is formed by this method, the light-emitting layer 54 can also be reduced in size compared to the other layers 51 to 53 and 55 to 57.

[0127] in addition, Fig.21 The organic layer OR shown can also be Figure 7 That is, the light emitting layer 54 may be formed in the first step P11, and the other layers 51 to 53 and 55 to 57 may be formed in the second step P12.

[0128] in addition, Fig.21 The organic layer OR shown can also be Fig. 9 That is, the light emitting layer 54 may be formed in the first step P21, and the other layers 51 to 53 and 55 to 57 may be formed in the second step P22.

[0129] [Eighth Embodiment]

[0130] In a first embodiment, it is envisaged that Figure 5 The case where each sub-pixel SP has a rectangular organic layer OR is shown. In this embodiment, another example of the organic layer OR arranged in the display area DA is disclosed.

[0131] Fig.23 FIG. 4 is a diagram showing an example of a sub-pixel SP and an organic layer OR according to the present embodiment. Figure 2 In the display area, the plurality of sub-pixels SP1 are arranged along the second direction Y, the plurality of sub-pixels SP2 are arranged along the second direction Y, and the plurality of sub-pixels SP3 are arranged along the second direction Y.

[0132] In addition, dummy sub-pixels DP1, DP2, and DP3 are arranged in the peripheral area SA. The dummy sub-pixels DP1, DP2, and DP3 are arranged along the second direction Y with the sub-pixels SP1, SP2, and SP3 arranged at the end of the display area DA in the second direction Y, respectively. The dummy sub-pixels DP1, DP2, and DP3 are pixels that are not useful for image display. For example, the dummy sub-pixels DP1, DP2, and DP3 have a first electrode E1 but do not have a pixel circuit 1. Alternatively, the dummy sub-pixels DP1, DP2, and DP3 have a first electrode E1 and a pixel circuit 1, but these first electrodes E1 and the pixel circuit 1 are not connected.

[0133] exist Fig.23 In the example, the organic layer OR is continuously arranged across a plurality of sub-pixels SP. Specifically, the organic layer OR1 emitting red light is arranged across a plurality of sub-pixels SP1 and a dummy sub-pixel DP1 arranged along the second direction Y, the organic layer OR2 emitting green light is arranged across a plurality of sub-pixels SP2 and a dummy sub-pixel DP2 arranged along the second direction Y, and the organic layer OR3 emitting blue light is arranged across a plurality of sub-pixels SP3 and a dummy sub-pixel DP3 arranged along the second direction Y. The organic layers OR1, OR2, and OR3 are arranged at intervals in the first direction X.

[0134] The organic layers OR1, OR2, and OR3 have a pair of sides Sa and Sb parallel to the second direction Y and a pair of sides Sc and Sd parallel to the first direction X. The sides Sa and Sb are located in both the display area DA and the peripheral area SA. The sides Sc and Sd are located in the peripheral area SA and not in the display area DA.

[0135] Fig.24 FIG. 1 is a diagram for explaining an example of the effect of the present embodiment. Fig.24 , the organic layer OR is formed using a linear deposition source LDS on a portion of the substrate SUB where the organic layer OR (OR1, OR2, OR3) is formed in the display device DSP. The mask used for deposition is omitted.

[0136] The linear evaporation source LDS has a plurality of holes arranged along the second direction Y, and molecules for forming the layers 51 to 57 are released from the holes. The substrate SUB moves along the scanning direction D, so that the entire substrate SUB is exposed to the molecules released from the linear evaporation source LDS. The scanning direction D is parallel to the first direction X.

[0137] For example, in Fig.24 Implementation Figure 7 The first step P11 and the second step P12 shown in FIG. Figure 5 In the case of the same island-shaped organic layer OR, the difference in the outer shape of the layer formed in the first step P11 and the second step P12 mainly appears in the sides intersecting the scanning direction D, that is, a pair of sides parallel to the second direction Y. Regarding the sides parallel to the scanning direction D, that is, a pair of sides parallel to the first direction X, the position difference may not be fully expressed.

[0138] In this regard, according to Fig.23 In the structure shown in FIG. 1 , the organic layer OR does not have sides Sc and Sd parallel to the first direction X in the display area DA. As for sides Sa and Sb parallel to the second direction Y, for example Figure 6 , Fig.16 as well as Figures 17 to 21 As shown, a shape in which the positions of the ends S1 to S7 of the respective layers 51 to 57 are different can be appropriately realized.

[0139] The sides Sc and Sd are located in the peripheral area SA, and the dummy sub-pixels DP1, DP2, and DP3 are interposed between the sides Sc and Sd and the display area DA. Therefore, even if the shapes of the layers 51 to 57 of the organic layer OR are defective in the sides Sc and Sd, the influence is unlikely to affect the sub-pixels SP1, SP2, and SP3.

[0140] [Ninth Embodiment]

[0141] The layer structure of the organic layer OR is not limited to Figure 4 The structure shown. In the organic layer OR, one of the layers 51 to 57 may be omitted. In addition, the organic layer OR may include layers having other functions in addition to the layers 51 to 57. Furthermore, the organic layer OR may have a double-row structure including two light-emitting layers.

[0142] Fig.25 The schematic cross-sectional view of the display device DSP having a double-row organic layer OR includes a first organic layer 100 in contact with a first electrode E1 , a second organic layer 200 in contact with a second electrode E2 , and an intermediate layer 300 located between the first organic layer 100 and the second organic layer 200 .

[0143] The end S100 of the first organic layer 100, the end S200 of the second organic layer 200, and the end S300 of the intermediate layer 300 are all located on the rib 14. Fig.25 In the example of FIG. 1 , the end portion S300 is covered by the second organic layer 200. Thus, the intermediate layer 300 is not in contact with the second electrode E2.

[0144] Fig.26 : is a diagram showing the energy levels of each layer of the organic layer OR according to the present embodiment. The first organic layer 100 includes a first carrier injection layer 101, a first carrier transport layer 102, a first carrier blocking layer 103, a first light-emitting layer 104 (EML), a second carrier blocking layer 105, and a second carrier transport layer 106. The second organic layer 200 includes a third carrier transport layer 201, a third carrier blocking layer 202, a second light-emitting layer 203 (EML), a fourth carrier blocking layer 204, a fourth carrier transport layer 205, and a second carrier injection layer 206. The intermediate layer 300 is located between the second carrier transport layer 106 and the third carrier transport layer 201.

[0145] In this embodiment, it is assumed that the first electrode E1 is an anode and the second electrode E2 is a cathode. For example, in this case, the first carrier injection layer 101 is a hole injection layer (HIL), the first carrier transport layer 102 and the third carrier transport layer 201 are hole transport layers (HTL), the first carrier blocking layer 103 and the third carrier blocking layer 202 are electron blocking layers (EBL), the second carrier blocking layer 105 and the fourth carrier blocking layer 204 are hole blocking layers (HBL), the second carrier transport layer 106 and the fourth carrier transport layer 205 are electron transport layers (ETL), and the second carrier injection layer 206 is an electron injection layer (EIL). In addition, the intermediate layer 300 is, for example, a charge generation layer (CGL) that generates electrons and holes according to a voltage.

[0146] The intermediate layer 300 as a charge generation layer is formed of, for example, a metal material, and is likely to generate leakage current when in contact with the second electrode E2. Moreover, when leakage current is generated through the intermediate layer 300, only one of the first light-emitting layer 104 and the second light-emitting layer 203 can emit light. Therefore, it is preferred that Fig.25 As shown, the end portion S300 of the intermediate layer 300 is covered by one of the layers constituting the second organic layer 200 .

[0147] The layer covering the end S300 is, for example, one, a plurality of, or all of the third carrier transport layer 201, the third carrier blocking layer 202, the fourth carrier blocking layer 204, the fourth carrier transport layer 205, and the second carrier injection layer 206. Moreover, the same structure as the organic layer OR exemplified in the above-mentioned embodiments may also be applied to one or both of the first organic layer 100 and the second organic layer 200.

[0148] In addition, the organic layer OR may include three or more organic layers each including a light-emitting layer and an intermediate layer disposed between these organic layers. In this case, by covering the end of each intermediate layer with an upper layer, the same effect as in the present embodiment can be obtained.

[0149] [Tenth embodiment]

[0150] Fig. 27 FIG. 1 is a schematic cross-sectional view of a display device DSP according to a tenth embodiment. Fig. 27 In the example of FIG. 1 , each layer 51 to 57 constituting the organic layer OR has Figure 6 Same shape as the example.

[0151] The first carrier injection layer 51 has a first region 51a and a second region 51b located between the first region 51a and the end S1. In the first region 51a, a dopant (e.g., a p-type dopant) is distributed at a first concentration for the main material (main material). In the second region 51b, a dopant is distributed at a second concentration lower than the first concentration for the main material. The first region 51a overlaps with the opening OP and contacts the first electrode E1. The second region 51b is located on the rib 14.

[0152] Fig.28 is a schematic top view of the first carrier injection layer 51. Figure 5 In the same way as in the example, it is assumed that the first carrier injection layer 51 is rectangular. Fig.28 In the example of FIG. 5 , the first region 51 a is, for example, in a rectangular shape that overlaps the entire opening OP. In addition, the second region 51 b is in a frame shape that surrounds the first region 51 a.

[0153] Fig.291 is a diagram showing an example of a method for forming the first carrier injection layer 51. A mask MSK having an opening corresponding to the organic layer OR is arranged on a substrate SUB in a portion where a layer below the organic layer OR is formed in the display device DSP.

[0154] The main material of the first carrier injection layer 51 is formed by the evaporation source DS1. The main material is doped with a dopant by the evaporation source DS2. Figure 7 In the first step P11 and the second step P12 shown, the range of molecules from the evaporation source DS2 reaching the substrate SUB through the opening of the mask MSK is larger than the range of molecules from the evaporation source DS1 reaching the substrate SUB through the opening. Thus, the first carrier injection layer 51 having the first region 51a and the second region 51b surrounding it can be formed.

[0155] The concentration of the dopant in the second region 51b is lower than that in the first region 51a, so the second region 51b has a higher resistance than the first region 51a. Therefore, according to the structure of this embodiment, the leakage current of the path through the end S1 and the vicinity of the first carrier injection layer 51 and reaching the second electrode E2 is suppressed.

[0156] Generally, dopant materials are active and may be degraded by the environment. Such degraded materials are likely to occur near the end S1. According to the structure of this embodiment, the concentration of the dopant in the second region 51b is low, so such degraded materials can be suppressed.

[0157] In addition, in this embodiment, an example is shown in which each layer 51 to 57 has Figure 6 In the case of the same shape as in the example, the first region 51a and the second region 51b are formed in the first carrier injection layer 51. The first region and the second region are not necessarily formed in the first carrier injection layer 51, and may be formed in one of the other layers 52 to 57. In addition, the first region and the second region may be formed in two or more layers of each layer 51 to 57. In addition, the first region and the second region may also be directed to Fig.10 , Figure 16 to Figure 21 or Fig.25 An organic layer OR having the shape shown is provided.

[0158] In each of the layers 51 to 57, more regions having different dopant concentrations may be provided in addition to the first region and the second region. In this case, for example, the dopant concentration may be lowered in regions closer to the ends of the layers.

[0159] The shapes of the first region and the second region are not limited to Fig.28 Shape shown. Fig.301 is a top view showing another example of the first region and the second region. Fig.23 The same sub-pixels SP1, SP2, SP3, dummy sub-pixels DP1, DP2, DP3 and organic layers OR1, OR2, OR3.

[0160] The first carrier injection layer 51 of the organic layers OR1, OR2, and OR3 respectively has a first region 51a and a second region 51b. In each of the organic layers OR1, OR2, and OR3, the second region 51b is formed in a ring shape along the sides Sa, Sb, Sc, and Sd. That is, the first region 51a of the organic layer OR1 is formed across the sub-pixel SP1 and the dummy sub-pixel DP1, the first region 51a of the organic layer OR2 is formed across the sub-pixel SP2 and the dummy sub-pixel DP2, and the first region 51a of the organic layer OR3 is formed across the sub-pixel SP3 and the dummy sub-pixel DP3. In addition, the first region and the second region may be formed in the layers other than the first carrier injection layer 51 in the organic layers OR1, OR2, and OR3.

[0161] Fig.30 The organic layers OR1, OR2, OR3 shown can be used as Fig.24 A linear evaporation source is formed as shown in FIG. Fig.29 Similarly, by separately using a linear vapor deposition source for a host material and a linear vapor deposition source for a dopant, the first region and the second region can be formed in specific layers of the organic layers OR1 , OR2 , and OR3 .

[0162] In the first to tenth embodiments above, such a structure is disclosed, and the organic layer OR includes a first layer having a first end, and a second layer located between the first layer and the second electrode E2 and having a second end, and the second layer covers the first end. The first layer is a layer other than the top layer among the layers constituting the organic layer OR, for example, in the first embodiment, it is the first carrier injection layer 51, the first carrier transport layer 52, or the light emitting layer 54. The second layer is a layer other than the bottom layer among the layers constituting the organic layer OR, for example, in the first embodiment, it is the first carrier blocking layer 53 or the second carrier blocking layer 55.

[0163] In addition, in the second embodiment ( Fig.16 ) and the third embodiment ( Fig.17 ) discloses such a structure, in addition to the first layer and the second layer, the organic layer OR further includes a third layer located between the second layer and the second electrode E2 and having a third end, and the third layer covers the second end. For example, in the second embodiment, the first layer is the first carrier injection layer 51 or the first carrier transport layer 52, the second layer is the first carrier blocking layer 53, and the third layer is the second carrier blocking layer 55.

[0164] The layer structure of the organic layer OR disclosed in each embodiment is an example. Even when the layer structure of the organic layer OR is different from that of each embodiment, the same effects as those of each embodiment can be obtained by providing the first layer and the second layer and the additional third layer.

[0165] In each embodiment, the first electrode E1 is equivalent to the anode and the second electrode E2 is equivalent to the cathode. However, even in the case where the second electrode E2 is equivalent to the anode and the first electrode E1 is equivalent to the cathode, the same effect as that of each embodiment can be obtained by applying the same structure as the organic layer OR disclosed in each embodiment.

[0166] All display devices obtained by appropriately modifying the design and implementing the display devices described above as the embodiments of the present invention by those skilled in the art belong to the scope of the present invention as long as they include the gist of the present invention.

[0167] It should be understood that within the scope of the concept of the present invention, those skilled in the art can think of various variations, and these variations also belong to the scope of the present invention. For example, for the above-mentioned embodiments, those skilled in the art appropriately add, delete or design changes the components, or add, omit or change the conditions of the processes, as long as they have the gist of the present invention, they are included in the scope of the present invention.

[0168] In addition, regarding other effects brought about by the methods described in the above-mentioned embodiments, effects that are obvious from the description of this specification or that can be appropriately thought of by those skilled in the art should of course be understood as effects brought about by the present invention.

Claims

1. A display device, characterized in that: have: a first electrode; an organic layer, disposed on the first electrode; and a second electrode covering the organic layer, The organic layer includes a first carrier injection layer, a first carrier transport layer, a first carrier blocking layer, a light emitting layer, a second carrier blocking layer, a second carrier transport layer, and a second carrier injection layer stacked from the first electrode toward the second electrode, The first carrier blocking layer covers an end portion of the first carrier injection layer and an end portion of the first carrier transport layer.

2. The display device according to claim 1, characterized in that The second carrier blocking layer covers an end portion of the light emitting layer.

3. The display device according to claim 2, characterized in that: The second carrier blocking layer contacts the first carrier blocking layer.

4. The display device according to claim 1, characterized in that An end portion of the first carrier blocking layer contacts the second electrode.

5. The display device according to any one of claims 1 to 4, characterized in that: The first carrier blocking layer includes a first side and a second side, The second carrier blocking layer covers the second side but does not cover the first side.

6. The display device according to any one of claims 1 to 4, characterized in that: The first carrier injection layer comprises: a first region having a dopant distributed at a first concentration; The second region is located between the first region and the end of the first carrier injection layer, and the dopant is distributed at a second concentration lower than the first concentration.

7. The display device according to claim 5, characterized in that: The first carrier injection layer comprises: a first region having a dopant distributed at a first concentration; The second region is located between the first region and the end of the first carrier injection layer, and the dopant is distributed at a second concentration lower than the first concentration.

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