TW202027314A - Light emitting device and electrodes thereof - Google Patents

Abstract

A light emitting device and electrodes thereof are provided in which the electrodes of the light emitting device include a first electrode and an auxiliary electrode. The auxiliary electrode is disposed on the first electrode and covers a portion of the first electrode. A material of the first electrode is a metal-doped metal oxide or a metal-doped alkali metal salt. A material of the auxiliary electrode is metal or alloy thereof.

Description

Light emitting device and its electrode

The present invention relates to a light-emitting device and its electrode.

Light-emitting devices, such as transparent light-emitting devices, can be used in life to enhance the convenience of information dissemination, such as smart window, advertising billboards, car monitors, etc., so they have attracted attention and become one of the important goals of technological development.

The light-emitting device is generally composed of an electrode layer, a light-emitting layer, driving elements, and various wires (such as scan lines, data lines, etc.), and the electrode layer can be a transparent electrode to facilitate light emission. In order for the transparent light-emitting device to have high luminous efficiency, the transparency and conductivity of the transparent electrode must be considered, especially when applied to a large-area light-emitting device panel, the conductivity of the light-emitting device must be considered.

In order to pursue high transparency, high-transparency electrodes can be introduced. However, traditional metal-based transparent electrodes will reduce the transmittance and affect the overall transmittance of the light-emitting device panel.

Another way to improve the penetration is to punch holes or perforations in the traditional metal-based transparent electrode, but this will cause uneven brightness, and increase the resistance value at the expense of conductivity, thereby affecting the device The luminous efficiency.

If the electrode of the transparent light-emitting device is made with a transparent metal oxide common cathode structure on the entire surface, a sputtering process is required, which will cause the surface of the light-emitting layer formed before the sputtering process of the electrode to be sputtered. And be destroyed.

The embodiment of the present invention provides an electrode of a light emitting device, which can achieve high penetration while maintaining high conductivity.

The embodiment of the present invention provides a light-emitting device having the above-mentioned electrode, which is applicable to a large-sized transparent display.

An embodiment of the present invention provides an electrode of a light-emitting device, including a first electrode and an auxiliary electrode. The auxiliary electrode is disposed on the first electrode and covers a part of the first electrode. The material of the first electrode is metal oxide or alkali doped with metal. Metal salts, the auxiliary electrode material includes metal or its alloy.

The embodiment of the present invention provides a light emitting device, including a substrate, an active element layer, an insulating layer, a pixel definition layer, a light emitting element, an auxiliary electrode, and a thin film packaging layer. The active element layer is disposed on the substrate; the insulating layer is disposed on the substrate and the active element The pixel definition layer is arranged on a part of the insulating layer; the light emitting element is arranged on the insulating layer and includes a first electrode, a light emitting layer, and a second electrode. The second electrode is arranged on the insulating layer and is located on the insulating layer and the picture. Between the element definition layers and electrically connected to the active device layer, the light-emitting layer is located between the second electrode and the first electrode; the auxiliary electrode is arranged on part of the first electrode and covers the active device layer; the thin film encapsulation layer Covering the light-emitting element and the auxiliary electrode; wherein the material of the first electrode is metal doped metal oxide or alkali metal salt, and the material of the auxiliary electrode includes metal or its alloy.

In order to make the present invention more obvious and easy to understand, the following specific embodiments are described in detail in conjunction with the accompanying drawings.

The following examples are listed in conjunction with the accompanying drawings for detailed description, but the provided examples are not intended to limit the scope of the present invention. In addition, the component sizes in the drawing formula are drawn for convenience of explanation, and do not represent the actual component size ratio. Moreover, although "first" and "second" are used in the text to describe different elements and/or layers, these elements and/or layers should not be limited by these terms. Rather, these terms are only used to distinguish one element or film layer from another element or film layer. Therefore, the first element or film layer discussed below may be referred to as the second element or film layer without departing from the teachings of the embodiments. To facilitate understanding, the same elements will be described with the same symbols in the following description.

In the description of the embodiments of the present invention, different examples may use repeated reference symbols and/or words. These repeated symbols or words are for the purpose of simplification and clarity, and are not used to limit the relationship between the various embodiments and/or the appearance structure. Furthermore, if the following disclosure of this specification describes forming a first feature on or above a second feature, it means that it includes an embodiment in which the formed first feature and the second feature are in direct contact , Also includes an embodiment in which an additional feature is formed between the first feature and the second feature, so that the first feature and the second feature may not be in direct contact. To facilitate understanding, the same elements will be described with the same symbols in the following description.

1A is a schematic cross-sectional view of a light-emitting device including electrodes according to a first embodiment of the present invention, and FIG. 1B is a top view of the light-emitting device including a plurality of pixels, wherein FIG. 1A is a drawing along the AA section line of FIG. 1B A schematic cross-sectional view of the light-emitting device shown.

1A, as shown in FIG. 1A, the electrode 110 of the light emitting device 100 of the first embodiment includes a first electrode 111 and an auxiliary electrode 112. The auxiliary electrode 112 is disposed on the first electrode 111 and covers a portion of the first electrode 111. .

The material of the first electrode 111 is a metal oxide or alkali metal salt doped with a metal; for example, the metal oxide may include but is not limited to LiO ₂ (lithium superoxide) or MoO ₃ (molybdenum trioxide); Salts include but are not limited to LiF (lithium fluoride), LiBO ₃ (lithium borate), K ₂ SiO ₃ (potassium silicate), Cs2CO3 (cesium carbonate), CH3COOM (acetate) (M is Li (lithium), Na (sodium), K (potassium), Rb (rubidium), or Cs (cesium)). Metals include but are not limited to Al (aluminum), Ca (calcium), Ag (silver), Cu (copper), Mg (magnesium) or alloys thereof, such as Mg:Ag, Li:Al, and the like. In the embodiment of FIG. 1A, the first electrode 111 can be fabricated by a co-evaporation method, such as co-evaporation using different evaporation sources in a vacuum chamber, so that the metal oxide can be vapor-deposited at a close weight or volume ratio. Compounds and metals, or alkali metal salts and metals, wherein the mixing weight ratio of metal to metal oxide or metal to alkali metal salt is, for example, between 2:1 and 1:5. In an embodiment according to the present invention The mixing weight ratio of metal to metal oxide or metal to alkali metal salt is, for example, 1:1 to 2:3, but the present invention is not limited to this. In addition, the thickness of the first electrode 111 is less than or equal to 30 nm. In one embodiment, the thickness of the first electrode 111 is, for example, 5-15 nm.

In addition to the metal oxide or alkali metal salt doped with metal, the material of the first electrode 111 can also be further doped with organic material to improve transparency.

The auxiliary electrode 112 includes a conductive metal material or alloy, including but not limited to Mg (magnesium), Al (aluminum), Ag (silver), Au (gold), and Cu (copper). The auxiliary electrode 112 may directly contact the first electrode 111, or other elements may be arranged between the auxiliary electrode 112 and the first electrode 111. The formation method of the auxiliary electrode 112 includes evaporation, in-jet printing (IJP), screen printing, sputtering, and the like. When the mixing weight of the metal and metal oxide or metal and alkali metal salt has a specific ratio and matches with the thickness of the first electrode 111, the first electrode 111 with high penetration and certain conductivity can be formed. The auxiliary electrode 112, which can increase the conductivity of the panel, can increase the transparency of the transparent light-emitting device.

Please refer to FIG. 1A again. The light-emitting device 100 of the first embodiment in FIG. 1A includes a light-emitting element 160, where the light-emitting element 160 may include a first electrode 111, a light-emitting layer 161 and a second electrode 162.

In an embodiment according to the present invention, the light-emitting element 160 may include a first carrier injection layer (not shown) and a first carrier injection layer (not shown) arranged in sequence from the second electrode 162 to the first electrode 111 A carrier transmission layer (not shown), a second carrier blocking layer (not shown), an emission layer 161, a first carrier blocking layer (not shown), The second carrier transport layer (not shown) and the second carrier injection layer (not shown). The first carrier and the second carrier may be different types of carriers, for example, the first carrier is an electron hole, and the second carrier is an electron, but according to the embodiment of the present invention It is not limited by this, it can be adjusted according to demand. The embodiment according to the present invention does not limit the composition of the light-emitting element 160 either. In an embodiment of the present invention, the light-emitting layer 161 is, for example, various possible organic light-emitting layers suitable for organic light-emitting devices, such as organic light-emitting diode (OLED) display devices, or suitable for quantum The inorganic light-emitting layer (or quantum dot light-emitting layer) of a quantum dot light-emitting diode (LED) display device; however, the embodiments according to the present invention are not limited thereto.

The second electrode 162 can be used as the anode of the light-emitting element 160, and the first electrode 111 can be used as the cathode of the light-emitting element 160. The anode and the cathode are used to provide current to the light-emitting layer 161 to emit light L. According to an embodiment of the present invention, in a transparent light-emitting element, the second electrode 162 and the first electrode 111 may both be transparent electrodes. The material of the second electrode 162 may include metal oxides, such as indium tin oxide (ITO), indium zinc oxide (IZO), aluminum-doped zinc oxide (AZO), zinc oxide (Zinc Oxide; ZnO) or gallium-doped zinc oxide (GZO), but not limited to these materials.

In one embodiment, the first electrode 111 adopts an evaporation process, and the auxiliary electrode 112 can also adopt an evaporation process. Therefore, when the Active Matrix OLED (AMOLED) is made, it is the same as the existing AMOLED process. High compatibility.

1A, the light-emitting device 100 further includes a substrate 120, an active device layer 130, an insulating layer 140, a pixel define layer (PDL) 150, a light-emitting device 160, an auxiliary electrode 112, a thin film encapsulation layer 170, and a cover板180. The light emitting element 160 includes a second electrode 162, a light emitting layer 161 and a first electrode 111. The active device layer 130 is disposed on the substrate 120, the insulating layer 140 is disposed on the substrate 120 and the active device layer 130, the second electrode 162 is disposed on the insulating layer and is electrically connected to the active device layer 130, and the pixel definition layer 150 is disposed on Part of the second electrode 162 and the insulating layer 140, the light-emitting layer 161 is disposed on the second electrode 162 and the pixel defining layer 150, the first electrode 111 is disposed on the light-emitting layer 161, and the auxiliary electrode 112 is disposed on the first electrode 111 It covers the active device layer 130 and exposes part of the first electrode 111, wherein the first electrode 111 is disposed between the auxiliary electrode 162 and the light-emitting layer 161. The thin film encapsulation layer 170 is disposed on the auxiliary electrode 112 and the first electrode 111 that is not covered by the auxiliary electrode 112, and the cover plate 180 is disposed on the thin film encapsulation layer 170. In addition, it is also possible to optionally form a buffer layer (not shown) on the substrate 120 first, and then form the other components mentioned above.

Please refer to FIGS. 1A and 1B at the same time. FIG. 1B is a top view of a light-emitting device 100 including a plurality of pixels. The light-emitting device 100 can define a plurality of pixels 190 through the pixel definition layer 150. Among these pixels 190 the second electrode a _E a _P light emitting layer region other than the region of this pixel in the plurality of pixels 190 defined 162, the light emitting layer 161 and 111 define a first electrode. The light-emitting layer 161 sandwiched between the second electrode 162 and the first electrode 111 can emit light L to form a light-emitting area A _E. In this embodiment, a plurality of pixels 190 are arranged in an array on the substrate 120. The light emitting device 100 includes a non-transmissive area A _O and a transmissive area _AT . The area outside the light-transmitting area _AT is the position where the auxiliary electrode 160 is disposed, and forms the non-light-transmitting area A _O. The light-transmitting area _AT includes a pixel defining layer area _AP and a light-emitting area A _E. That is, the auxiliary electrode 112 is disposed in the non-transmissive area A _O , and the auxiliary electrode 112 covers the active device layer 120. The auxiliary electrode 112 can selectively cover all the pixel definition layers 150.

Please refer to FIGS. 1A and 1B again. In this embodiment, the color of the light emitted by the light-emitting layer 161 of each of the plurality of pixels 190 and the light emitted by the light-emitting layer 161 of the adjacent pixels The colors can be the same or different. The light emitting layer 161 of the light emitting device 100 includes a first color light emitting layer (for example, the light emitting area shown in FIG. 1B is A _E1 ) and a second color light emitting layer (for example, the light emitting area shown in FIG. 1B is A _E2 ) and the third color light-emitting layer (for example, the light-emitting area shown in FIG. 1B is A _E3 ). In the embodiment shown in FIG. 1B, the light-emitting areas A _E1 , A _E2 and A _{E3 are} along the substrate 120 as shown The first direction D1 shown in 1B is sequentially and repeatedly arranged, and in the second direction D2, the light-emitting areas A _E1 , A _E3 and A _{E2 are} repeatedly arranged in the order. The first direction D1 is substantially perpendicular to the second direction D2. In one embodiment, the color of the light emitted by the light-emitting layer 161 of each pixel, such as the first color, the first color, and the third color, may be red, blue, and green, respectively, but in other embodiments, The first color, the first color, and the third color may also be other colors, and the present invention does not limit the colors of the first color, the first color, and the third color. In addition, the above description is based on the example that the light emitting device 100 includes three pixel colors, but the light emitting device 100 may also include three or more or less than three pixel colors, which is not limited in the present invention.

The arrangement of pixels of different colors in the embodiment shown in FIG. 1B is only an example, and the present invention does not limit the arrangement of pixels. In addition, the areas of pixels of different colors can be the same or different, and the present invention does not deal with it. This is limited.

Please refer to FIG. 1C. FIG. 1C shows a schematic cross-sectional view of a light-emitting device 100 including a plurality of pixels 190, and FIG. 1C only shows some elements of the light-emitting device 100. As shown in FIG. 1C, the light-emitting device 100 only shows the substrate 120, the active device layer 130, the light-emitting device 160, and the auxiliary electrode 112. The light-emitting element 160 includes a structure 160 ′ composed of a second electrode and a light-emitting layer, a first electrode 111 and an auxiliary electrode 112. If the second electrode has been fabricated in the active device layer 130, the structure 160' can be a light-emitting layer. The light-emitting device 100 of FIG. 1C may also include the components shown in FIGS. 1A and 1B but not shown in FIG. 1C, which will not be repeated here. The auxiliary electrode 112 has a patterned structure, the area where the auxiliary electrode 112 is located is the non-transmissive area A _O , and the area between the auxiliary electrodes 160 is the light-transmitting area _AT .

The substrate 120 is, for example, a flexible substrate. The material of the substrate 120 includes glass, metal foil, plastic material or polymer material, such as polyimide (PI), polyimide, and inorganic materials. Mixture (hybrid PI), polyethylene terephthalate (PET), polyethersulfone (PES), polyacrylate (PA), polyethylene naphthalate (Polyethylene naphthalatc) , PEN), polycarbonate (PC), polynorbornene (PNB), polyetherimide (PEI), polyetheretherketone (PEEK), cycloolefin polymer (Cyclo olefin polymer, COP), polymethyl methacrylate (PMMA), glass fiber reinforced plastic substrate (Glass Fiber Reinforced Plastic, GFRP), carbon fiber reinforced polymer composite (Carbon Fiber Reinforced Polymer, CFRP), etc. or other applicable Made of soft materials. However, in other embodiments not shown, the substrate 110 can also be made of glass or other hard materials. Alternatively, the substrate 120 may also be a composite substrate made of multiple layers of organic materials and/or inorganic materials with water and gas blocking function, so that it has the function of blocking water and gas. The invention does not limit the type and composition of the substrate 120.

The active device layer 130 includes, for example, a thin film transistor (TFT), which may be an organic thin film transistor (OTFT), but the present invention does not limit the active device layer 130 to include a thin film transistor or the thin film transistor. The crystal is an organic thin film transistor.

The insulating layer 140 is, for example, an organic passivation layer (OPV), and a patterning process can be performed to electrically connect the second electrode 162 and the active device layer 130.

The pixel definition layer 150 is, for example, a photosensitive resin (photosensitive resin). The thin film encapsulation layer 170 may include a plurality of inorganic thin films stacked on each other. The aforementioned inorganic thin films include alternately stacked silicon nitride films and silicon oxycarbide (SiOC) films. However, other embodiments according to the present invention do not limit the number of layers and materials of the inorganic thin film. In these other embodiments, the thin film encapsulation layer 170 includes a single layer or multiple layers of organic thin films or alternately stacked inorganic thin films. The combination of the above. For example, inorganic materials include aluminum oxide (Al ₂ O ₃ ), silicon oxide (SiO _x ), silicon nitride (SiN _x ), silicon oxynitride (SiO _x N _y ), or silicon oxycarbide (SiOC) ; Organic materials include parylene (parylene), polymer (polymer) or acrylic (acrylic). It can be changed appropriately according to actual design requirements.

The cover plate 180 is, for example, a flexible substrate, and the material of the cover plate 180 includes glass, metal foil, plastic material or polymer material, such as polyimide (PI), polyimide, and inorganic mixtures. (hybrid PI), polyethylene terephthalate (PET), polyethersulfone (PES), polyacrylate (PA), polyethylene naphthalate (Polyethylene naphthalatc, PEN), polycarbonate (PC), polynorbornene (PNB), polyetherimide (PEI), polyetheretherketone (PEEK), cyclic olefin polymer (Cyclo olefin) polymer, COP), polymethyl methacrylate (PMMA), glass fiber reinforced plastic substrate (Glass Fiber Reinforced Plastic, GFRP), carbon fiber reinforced polymer composite (Carbon Fiber Reinforced Polymer, CFRP), etc. or other applicable soft Made of materials. However, in other embodiments not shown, the cover plate 180 can also be made of glass or other hard materials. Alternatively, the cover plate 180 can also be a composite substrate made of multilayer organic materials and/or inorganic materials with a water and gas barrier function, so that it has a water and gas barrier function. The invention does not limit the types of the substrate cover plate 180. And composition.

Please refer to FIG. 2, which is a schematic diagram of the relationship between the thickness of the auxiliary electrode and the viewing angle of the viewer. The light-emitting device 200 of FIG. 2 only shows the substrate 120, the second electrode 162, the pixel definition layer 150, the light-emitting layer 161, the first electrode 111 and the auxiliary electrode 112, and does not show the other elements as shown in FIG. 1A. The thickness of the first electrode 111 is t ₁ , and t _{1 is} less than 30 nm. When the thickness of the auxiliary electrode 112 is t ₂₁ and t ₂₂ , respectively (t _{22 is} greater than t ₂₁ ), the visual line of sight of the viewer 210 is V1 and V2, respectively. It can be seen that the thickness of the auxiliary electrode 112 is t ₂₁ and t ₂₂ , respectively. The viewing angle of the viewer 210 is different. When the auxiliary electrode 112 has a smaller thickness t ₂₁ , the viewing angle of the viewer 210 is larger. When the auxiliary electrode 112 has a larger thickness t ₂₂ , the viewing angle of the viewer 210 is smaller. The high resistance of the cathode of the light-emitting device 200 can easily cause uneven light emission of the light-emitting device 200. The total resistance of the cathode of the light-emitting device 200 is determined by the first electrode 111 and the auxiliary electrode 112, which are connected in parallel. The first electrode 111 When the resistance value of the auxiliary electrode 112 becomes larger, the resistance value of the auxiliary electrode 112 must be lowered to avoid uneven light emission of the light-emitting device 200. However, in order to improve the transparency of the light-emitting device 200, the thickness of the first electrode 111 should be thin, that is, the thickness of the first electrode 111 is inversely related to the transparency of the light-emitting device 200, and the thickness of the auxiliary electrode 112 needs to be increased to make the cathode The total resistance value is within a certain range, so as to avoid uneven light emission of the light-emitting device 200. However, as described above, too thick the auxiliary electrode 112 will affect the viewing angle of the viewer 210. Therefore, the thickness of the auxiliary electrode 112 needs to be matched with the thickness of the first electrode 111 to achieve the requirements of high transparency and uniform light emission of the transparent light-emitting device 200. Therefore, when the thickness of the first electrode 111 is less than or equal to 30 nm, the thickness of the auxiliary electrode 112 It is 300 nm to 1500 nm. In one embodiment, the thickness of the first electrode 111 is, for example, 10 nm, and the thickness of the auxiliary electrode 112 is, for example, 500 nm.

The display device completed by the above-mentioned embodiments can be applied to transparent displays of medium and large sizes, such as transparent displays of 15 inches or more.

3 is a schematic cross-sectional view of a light-emitting device including transparent electrodes according to a second embodiment of the present invention.

Please refer to FIG. 3. As shown in FIG. 3, the light-emitting device 300 of this embodiment is similar to the light-emitting device 100 of the first embodiment described in FIG. 1C, so the same components are represented by the same component symbols, and please refer to the first The description in the embodiment will not be repeated here. The main difference between the light-emitting device 300 and the light-emitting device 100 is that the metal doped in the metal oxide or alkali metal salt in the first electrode 111 of the light-emitting device 300 includes at least two different metals. Metals include but are not limited to Al (aluminum), Ca (calcium), Ag (silver), Cu (copper), Mg (magnesium) or alloys thereof, such as Mg:Ag, Li:Al, and the like. In the embodiment shown in FIG. 3, the production of the first electrode 111 can also adopt a co-evaporation method. For example, the co-evaporation method is performed by using different evaporation sources in a vacuum chamber, so that it can be vaporized at the same time in a close weight or volume ratio. Metal oxide and at least two different metals, or alkali metal salts and at least two metals, wherein the mixing weight ratio of the at least two metals and the metal oxide or the metal and the alkali metal salt is, for example, 2:1~1 : 5, but the embodiment of the present invention is not limited to the range of the mixing weight ratio. The materials of at least two different metals doped in metal oxides or alkali metal salts include, but are not limited to, Al (aluminum), Ca (calcium), Ag (silver), Cu (copper), Mg (magnesium) Or its alloys, such as Mg:Ag, Li:Al, etc. The mixing weight ratio of at least two different metals doped in metal oxides or alkali metal salts is, for example, between 2:1 and 1:5, but the embodiments of the present invention are not limited to the range of the mixing weight ratio . In the embodiment shown in FIG. 3, the thickness of the first electrode 111 is less than or equal to 30 nm.

In this embodiment, the first electrode 111 formed by doping two different metals in metal oxides or alkali metal salts can improve its conductivity or electron injection ability, and then cooperate with an auxiliary electrode, such as the first electrode Patterned auxiliary electrodes on 111 can reduce the impedance of the electrodes in series.

4 is a schematic cross-sectional view of a light-emitting device including transparent electrodes according to a third embodiment of the present invention.

Please refer to FIG. 4, as shown in FIG. 4, the light-emitting device 400 of this embodiment is similar to the light-emitting device 100 of the first embodiment described in FIG. 1C, so the same components are represented by the same component symbols and will not be repeated here. Narrative. The main difference between the light emitting device 400 and the light emitting device 100 is that the light emitting device 400 further includes a metal oxide layer 410 disposed between the first electrode 111 and the auxiliary electrode 112. The material of the metal oxide layer 410 includes indium tin oxide (ITO), indium zinc oxide (IZO), aluminum-doped zinc oxide (AZO), and zinc oxide (Zinc Oxide; ZnO). ) Or gallium-doped zinc oxide (GZO), etc., but the embodiments of the present invention are not limited to the foregoing materials. The thickness of the metal oxide layer 410 is less than 200 nm. The formation method of the metal oxide layer 410 may include sputtering. In the embodiment shown in FIG. 4, the metal doped in the metal oxide or alkali metal salt may also include at least two different metals. If the first electrode 111 is formed by doping a metal with a metal oxide, the metal oxide layer 410 and the metal oxide in the first electrode 111 may be the same or different.

In the embodiment shown in FIG. 4, a metal oxide layer 410 is provided between the first electrode 111 and the auxiliary electrode 112, which can further improve the uniformity and transparency of the panel.

5 is a schematic cross-sectional view of a light-emitting device including transparent electrodes according to a fourth embodiment of the present invention.

Please refer to FIG. 5. As shown in FIG. 5, the light-emitting device 500 of this embodiment is similar to the light-emitting device 100 of the first embodiment described in FIG. 1C, so the same components are represented by the same component symbols, and please refer to the first The description in the embodiment will not be repeated here. The main difference between the light-emitting device 500 and the light-emitting device 100 is that the light-emitting device 500 further includes a metal layer 510 disposed between the first electrode 111 and the auxiliary electrode 112 and an optical matching layer 520 covering the auxiliary electrode 112; the optical matching layer 520 can be shared Conformally formed on the auxiliary electrode 112, the optical matching layer 520 covers the upper surface, side surfaces of the auxiliary electrode 112 and the surface of the metal layer 510 exposed by the auxiliary electrode 112. The material of the metal layer 510 includes silver (Ag), gold (Au), etc., but is not limited thereto. The thickness of the metal layer 510 is about 5 nm to 10 nm, and the transmittance is greater than or equal to 50%. The method of forming the metal layer 510 includes vapor deposition. The material of the optical matching layer 520 may be, for example, a hole transport layer (HTL) material, but is not limited thereto. The thickness of the optical matching layer 520 is about 5 to 150 nm, and the refractive index is 1.3 to 2.5. The method of forming the optical matching layer 520 includes evaporation. By adjusting the material (refractive index) of the optical matching layer 520, the total reflection phenomenon in each film layer of the device can be reduced and the absorption peak of the metal layer 510 of the penetrating light can be adjusted, thereby increasing the light extraction efficiency. In the embodiment shown in FIG. 5, the metal doped in the metal oxide or alkali metal salt may also include at least two different metals.

In the embodiment shown in FIG. 5, the optical matching layer 520 may be omitted according to design requirements. Compared with using a transparent conductive oxide (such as ITO, etc.) as an electrode, the use of the metal layer 510 in the embodiment shown in FIG. 5 can increase the conductivity, the thickness can also be smaller than that of the transparent conductive oxide, and the yellowing rate The (yellowness index) b* is small and does not require an additional sputtering chamber. Due to the arrangement of the metal layer 510 and the optical matching layer 520, the uniformity and transparency of the panel of the light-emitting device can be further improved.

6 is a schematic cross-sectional view of a light-emitting device including transparent electrodes according to a fifth embodiment of the present invention.

Please refer to FIG. 6, as shown in FIG. 6, the light-emitting device 600 of this embodiment is similar to the light-emitting device 400 of the third embodiment described in FIG. 4, so the same components are represented by the same component symbols, and please refer to the third embodiment. The description in the embodiment will not be repeated here. The main difference between the light emitting device 600 and the light emitting device 400 is that the light emitting device 600 further includes an alienation layer 610 disposed on the metal oxide layer 410 exposed by the auxiliary electrode 112. The alienation layer 610 may include an organic material with a thickness of about 20-30 nm, and its formation method includes evaporation. The alienation layer 610 may have optical matching. In one embodiment, the patterned isolation layer 610 may be formed first, and then the patterned auxiliary electrode 112 may be formed by, for example, evaporation. In an embodiment, the metal oxide layer 410 may be replaced by a metal layer or the metal oxide layer 410 may be omitted. The metal layer may include silver (Ag) or gold (Au), and the thickness is, for example, about 5 nm to 10 nm. In addition, in the embodiment shown in FIG. 6, the metal doped in the metal oxide or alkali metal salt may also include at least two different metals.

In the embodiment shown in FIG. 6, the first electrode 111 cooperates with the metal oxide layer 410 and the auxiliary electrode 112 to further improve the uniformity and transparency of the panel of the light-emitting device. Wherein, the auxiliary electrode 112 can be added with an isolation layer 610 with optical matching to perform metal patterning to improve transparency.

Next, optical simulations are performed with light-emitting devices with different structures to illustrate the optical effects of the light-emitting devices according to the embodiments of the present invention. 7A and 7B show the structure of the first group of light-emitting devices used in the optical simulation. FIG. 7C is an optical simulation result of the structure of the first group of light-emitting devices.

Please refer to Figure 7A and Figure 7B first. FIG. 7A is a light-emitting device 700A according to an embodiment of the present invention used in optical simulation. The structure shown in FIG. 7A only includes the light-emitting area A _E. The light emitting device 700A includes a substrate 120, a light emitting layer 161, a first electrode 111, a metal layer 510, and a cover plate 180. The light-emitting layer 161 is disposed on the substrate 120, the first electrode 111 is disposed on the light-emitting layer 161, the metal layer 510 is disposed on the first electrode 111, and the cover plate 180 is disposed on the metal thin film 510. The material of the metal layer 510 is silver (Ag), and the materials of the substrate 120, the light-emitting layer 161, the first electrode 111, the metal thin film 510, and the cover 180 can refer to the foregoing embodiments. The first electrode 111 is an alkali metal salt-based LiF doped with metallic aluminum (Al), and the mixing weight ratio of Al and LiF is 2:3. The thickness of the light emitting layer 161, the first electrode 111, the metal layer 510, and the cover 180 of the light emitting device 700A are 100 nm, 7 nm, 7 nm, and 20 nm, respectively.

FIG. 7B shows a light-emitting device 700B of a comparative example. The light-emitting device 700B includes a substrate 120, a light-emitting layer 161, a first electrode 111, an electrode 710, and a cover plate 180. The light emitting layer 161 is disposed on the substrate 120, the first electrode 111 is disposed on the light emitting layer 161, the electrode 710 is disposed on the first electrode 111, and the cover plate 180 is disposed on the electrode 710. The material of the electrode 710 is Indium Zinc Oxide (IZO). The thickness of the light-emitting layer 161, the first electrode 111, the electrode 710, and the cover plate 180 of the light-emitting device 700B are 100 nm, 7 nm, 7 nm, and 20 nm, respectively. The materials of the substrate 120, the light-emitting layer 161, the first electrode 111, and the cover 180 of the light-emitting device 700B are the same as the materials of the corresponding elements in the light-emitting device 700A.

Figure 7C shows the optical simulation results of different light-emitting devices. That is, FIG. 7C depicts the optical simulation results of the light-emitting device 700A and the light-emitting device 700B of the comparative example. The horizontal axis of Fig. 7C is the wavelength, and the unit is nm; the vertical axis is the transmittance (Transmittance). The solid curve is the relationship between the wavelength and the transmittance of the light-emitting device 700A, and the dotted curve is the relationship between the wavelength and the transmittance of the light-emitting device 700B of the comparative example. It can be seen from Fig. 7C that the wavelength range of visible light (about 400nm~700nm) At the same wavelength, the transmittance of the light-emitting device 700A is higher than that of the light-emitting device 700B. The embodiment of the present invention uses metal doped metal oxides or alkali metal salts and auxiliary electrodes as cathodes. However, since the auxiliary electrodes are arranged in the non-luminous area of the light-emitting device, the simulated device does not include the auxiliary electrodes. The light-emitting device 700A uses silver metal and the first electrode 111 as a cathode, while the light-emitting device 700B of the comparative example uses a transparent metal oxide (such as IZO) and the first electrode 111 as a cathode. The light emission of the embodiment of the present invention can be seen from FIG. 7C. The higher transmittance of the device also makes the light emitting device have a lower yellowing rate.

8A and 8B show the structure of the second group of light-emitting devices used in the optical simulation. FIG. 8C is an optical simulation result of the structure of the second group of light-emitting devices.

Please refer to FIGS. 8A and 8B first. FIGS. 8A and 8B show another light-emitting device structure used in the optical simulation. FIG. 8A is a light-emitting device 800A according to an embodiment of the present invention used in optical simulation, and the structure shown in FIG. 8A only includes the light-emitting area A _E. The light emitting device 800A includes a substrate 120, a light emitting layer 161, a first electrode 111, a metal layer 510, and a cover plate 180. The light-emitting layer 161 is disposed on the substrate 120, the first electrode 111 is disposed on the light-emitting layer 161, the metal layer 510 is disposed on the first electrode 111, and the cover plate 180 is disposed on the metal thin film 510. The material of the metal layer 510 is silver (Ag), and the materials of the substrate 120, the light-emitting layer 161, the first electrode 111, the metal thin film 510, and the cover 180 can refer to the foregoing embodiments. The first electrode 111 is an alkali metal salt-based LiF doped with metallic aluminum (Al), and the mixing weight ratio of Al and LiF is 2:3. The difference between the light-emitting device 800A and the light-emitting device 700A is that the thickness of the light-emitting layer 161, the first electrode 111, the metal layer 510, and the cover 180 of the light-emitting device 800A are 40 nm, 7 nm, 14 nm, and 40 nm, respectively.

8B is a light-emitting device 800B of a comparative example. The light-emitting device 800B includes a substrate 120, a light-emitting layer 161, a first electrode 111, and an electrode 810. The light emitting layer 161 is disposed on the substrate 120, the first electrode 111 is disposed on the light emitting layer 161, and the electrode 810 is disposed on the first electrode 111. The material of the electrode 810 is Indium Zinc Oxide (IZO). The thickness of the light-emitting layer 161, the first electrode 111, and the electrode 810 of the light-emitting device 800B are 40 nm, 7 nm, and 300 nm, respectively. The materials of the substrate 120, the light-emitting layer 161, and the first electrode 111 of the light-emitting device 800B are the same as the materials of the corresponding elements in the light-emitting device 800A.

Figure 8C shows the optical simulation results of different light-emitting devices. That is, FIG. 8C depicts the optical simulation results of the light-emitting device 800A and the light-emitting device 800B of the comparative example. The horizontal axis of FIG. 8C is the wavelength, and the unit is nm; the vertical axis is the transmittance (Transmittance). The solid curve is the relationship curve between the wavelength and the transmittance of the light-emitting device 800A, and the dotted curve is the relationship curve between the wavelength and the transmittance of the light-emitting device 800B of the comparative example. Table 1 shows the transmittance (%), yellowing rate b*, and conductivity (Ω/□, the unit of conductivity can be ohm meters or ohm centimeters) of the light emitting device 800A and the light emitting device 800B of the comparative example. It can be seen from FIG. 8C and Table 1 that at a wavelength of 550 nm, although the transmittance of the light-emitting device 800A is low, its yellowing rate is greatly reduced to -3.3 compared with the yellowing rate of the light-emitting device 800B of 14.7. The embodiment of the present invention uses metal doped metal oxides or alkali metal salts and auxiliary electrodes as cathodes. However, since the auxiliary electrodes are arranged in the non-luminous area of the light-emitting device, the simulated device does not include the auxiliary electrodes.

Table 1 Device Penetration rate (%) Yellowing rate b* Conductivity (Ω/□) 800A 77.2 14.7 27.9 800B 64.4 -3.3 40

9A and 9B show the structure of the third group of light-emitting devices used in the optical simulation. FIG. 9C is an optical simulation result of the structure of the third group of light-emitting devices.

Please refer to FIGS. 9A and 9B first. FIGS. 9A and 9B show the third group of light-emitting device structures used in the optical simulation. The light emitting device 900A shown in FIG. 9A only includes the light emitting area A _E. The light emitting device 900A includes a substrate 120, a light emitting layer 161 and a first electrode 111. The light emitting layer 161 is disposed on the substrate 120 and the first electrode 111 is disposed on the light emitting layer 161. The materials of the substrate 120, the light-emitting layer 161, and the first electrode 111 can refer to the foregoing embodiments. The first electrode 111 is an alkali metal salt-based LiF doped with metallic aluminum (Al), and the mixing weight ratio of Al and LiF is 2:3. The thickness of the light emitting layer 161 and the first electrode 111 of the light emitting device 900A are 40 nm and 7 nm, respectively.

9B is a light emitting device 900B of a comparative example. The light emitting device 900B includes a substrate 120, a light emitting layer 161, a metal layer 510 (as an electrode), and a cover plate 180. The light-emitting layer 161 is disposed on the substrate 120, the metal layer 510 is disposed on the light-emitting layer 161, and the cover plate 180 is disposed on the metal layer 510. The thickness of the light-emitting layer 161, the metal layer 510, and the cover plate 180 of the light-emitting device 900B are 40 nm, 14 nm, and 40 nm, respectively. The materials of the substrate 120 and the light-emitting layer 161 of the light-emitting device 900B are the same as the materials of the corresponding elements in the light-emitting device 900A.

Figure 9C shows the optical simulation results of different light-emitting devices. That is, FIG. 9C depicts the optical simulation results of the light-emitting device 900A and the light-emitting device 900B of the comparative example. The horizontal axis of FIG. 9C is the wavelength, and the unit is nm; the vertical axis is the transmittance (Transmittance). The solid line curve is the wavelength and transmittance curve of the light emitting device 900A, and the dashed curve is the wavelength and transmittance curve of the light emitting device 900B of the comparative example. It can be seen from Fig. 9C that in the visible light wavelength range (about 400nm~700nm), compared with the metal layer as the electrode compared with the metal layer as the electrode, the light emitting device is at the same wavelength. The transmittance of 900A is higher than that of the light emitting device 900B. The embodiment of the present invention uses metal doped metal oxides or alkali metal salts and auxiliary electrodes as cathodes. However, since the auxiliary electrodes are arranged in the non-luminous area of the light-emitting device, the simulated device does not include the auxiliary electrodes.

10A and 10B show the structure of the fourth group of light-emitting devices used in the optical simulation. FIG. 10C is an optical simulation result of the structure of the fourth group of light-emitting devices.

Please refer to FIGS. 10A and 10B first. FIGS. 10A and 10B show the structure of the fourth group of light-emitting devices used in the optical simulation. The structure shown in FIG. 10A only includes the light-emitting area A _E. The light emitting device 1000A includes a substrate 120, a light emitting layer 161, a first electrode 111, a metal layer 510, and a cover plate 180. The light-emitting layer 161 is disposed on the substrate 120, the first electrode 111 is disposed on the light-emitting layer 161, the metal layer 510 is disposed on the first electrode 111, and the cover plate 180 is disposed on the metal thin film 510. The material of the metal layer 510 is silver (Ag), and the materials of the substrate 120, the light-emitting layer 161, the first electrode 111, the metal thin film 510, and the cover 180 can refer to the foregoing embodiments. The first electrode 111 is an alkali metal salt-based LiF doped with metallic aluminum (Al), and the mixing weight ratio of Al and LiF is 2:3. The thickness of the light-emitting layer 161, the first electrode 111, the metal layer 510, and the cover plate 180 of the light-emitting device 1000A are 40 nm, 7 nm, 14 nm, and 40 nm, respectively.

10B is a light-emitting device 1000B of a comparative example. The light-emitting device 1000B includes a substrate 120, a light-emitting layer 161, a metal layer 510 (as an electrode), and a cover plate 180. The light-emitting layer 161 is disposed on the substrate 120, the metal layer 510 is disposed on the light-emitting layer 161, and the cover plate 180 is disposed on the metal layer 510. The thickness of the light-emitting layer 161, the metal layer 510, and the cover plate 180 are 40 nm, 14 nm, and 40 nm, respectively. The materials of the substrate 120 and the light-emitting layer 161 of the light-emitting device 1000B are the same as the materials of the corresponding elements in the light-emitting device 1000A.

Figure 10C shows the optical simulation results of different light-emitting devices. That is, FIG. 10C depicts the optical simulation results of the light-emitting device 1000A and the light-emitting device 1000B of the comparative example. The horizontal axis of FIG. 10C is the wavelength, and the unit is nm; the vertical axis is the transmittance (Transmittance). The solid line curve is the wavelength and transmittance curve of the light emitting device 1000A, and the dashed curve is the wavelength and transmittance curve of the light emitting device 1000B of the comparative example. It can be seen from Fig. 10C that in the visible light wavelength range (about 400nm~700nm), the alkali metal salt-type LiF doped with aluminum (Al) is used as the electrode compared with the metal layer as the electrode, except for the short wavelength (about 425nm) Below), at the same wavelength, the transmittance of the light-emitting device 1000A is higher than the transmittance of the light-emitting device 1000B of the comparative example. It can be seen that adding metal-doped alkali metal salts as the electrode layer can reduce the surface plasma effect (Surface Plasmon Polariton, SPP) and increase the transmittance. The embodiment of the present invention uses metal doped metal oxides or alkali metal salts and auxiliary electrodes as cathodes. However, since the auxiliary electrodes are arranged in the non-luminous area of the light-emitting device, the simulated device does not include the auxiliary electrodes.

In summary, the embodiments of the present invention include the use of metal-doped metal oxides or alkali metal salts with auxiliary electrodes as the electrodes of the light-emitting device, which is compatible with the existing AMOLED process and does not require complicated process and structural design , The overall penetration of the electrode can be improved and high conductivity can be maintained, and it can also be widely used in transparent products to achieve the effects of increased penetration and increased luminous efficiency.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the relevant technical field can make some changes and modifications without departing from the spirit and scope of the present invention. The scope of protection of the present invention shall be subject to those defined by the attached patent scope.

100, 200, 300, 400, 500, 600, 700A, 700B: light emitting device 110: electrode 111: first electrode 112: auxiliary electrode 120: substrate 130: active component layer 140: insulating layer 150: pixel definition layer 160: Light-emitting element 160': structure 161: light-emitting layer 162: second electrode 170: thin film encapsulation layer 180: cover plate 190: pixel 210: viewer 410: metal oxide layer 510: metal thin film 520: optical matching layer 610: alienation layer 710: electrode A _O: opaque region A _T: a light-transmitting region A _P: pixel definition layer region _{A E, A E1, A E2} , A E3: light emitting region D1, D2: direction L: light t _1, t ₂₁ , t ₂₂ : thickness V1, V2: line of sight

1A is a schematic cross-sectional view of a light emitting device including electrodes according to the first embodiment of the present invention. Fig. 1B is a top view of a light-emitting device including a plurality of pixels. FIG. 1C is a schematic cross-sectional view of a light-emitting device including a plurality of pixels. 2 is a schematic diagram of the relationship between the thickness of the auxiliary electrode and the viewing angle of the viewer. 3 is a schematic cross-sectional view of a light emitting device including electrodes according to a second embodiment of the invention. 4 is a schematic cross-sectional view of a light emitting device including electrodes according to a third embodiment of the invention. 5 is a schematic cross-sectional view of a light-emitting device including electrodes according to a fourth embodiment of the present invention. 6 is a schematic cross-sectional view of a light-emitting device including electrodes according to a fifth embodiment of the present invention. 7A and 7B show the structure of the first group of light-emitting devices used in the optical simulation. FIG. 7C is an optical simulation result of the structure of the first group of light-emitting devices. 8A and 8B show the structure of the second group of light-emitting devices used in the optical simulation. FIG. 8C is an optical simulation result of the structure of the second group of light-emitting devices. 9A and 9B show the structure of the third group of light-emitting devices used in the optical simulation. FIG. 9C is an optical simulation result of the structure of the third group of light-emitting devices. 10A and 10B show the structure of the fourth group of light-emitting devices used in the optical simulation. FIG. 10C is an optical simulation result of the structure of the fourth group of light-emitting devices.

100: Light-emitting device

110: Electrode

111: first electrode

112: auxiliary electrode

120: substrate

130: active component layer

140: insulating layer

150: pixel definition layer

160: light-emitting element

161: Emitting layer

162: second electrode

170: Thin film encapsulation layer

180: cover

A _O : non-transmissive area

A _T : Transmissive area

A _P: pixel definition layer region

A _E : Light emitting area

L: light

Claims (20)

An electrode of a light emitting device, including: The first electrode; and The auxiliary electrode is arranged on the first electrode and covers part of the first electrode, wherein the material of the first electrode is a metal oxide or alkali metal salt doped with a metal, and the material of the auxiliary electrode includes Metal or its alloys. The electrode of the light-emitting device according to the first item of the patent application, wherein the metal oxide includes LiO ₂ (lithium superoxide) or MoO ₃ (molybdenum trioxide) and the alkali metal salt includes LiF (lithium fluoride) ), LiBO ₃ (lithium borate), K ₂ SiO ₃ (potassium silicate), Cs ₂ CO ₃ (cesium carbonate) or CH ₃ COOM (acetate), M is Li (lithium), Na (sodium), K ( Potassium), Rb (rubidium) or Cs (cesium). The electrode of the light-emitting device according to the scope of the patent application, wherein the metal doped in the first electrode includes Al (aluminum), Ca (calcium), Ag (silver), Cu (copper), Mg (Magnesium) or its alloys. The electrode of the light-emitting device according to the scope of the patent application, wherein the metal doped in the first electrode includes at least two different metals, and the at least two different metals include Al (aluminum), Ca (calcium), Ag (silver), Cu (copper), Mg (magnesium) or alloys thereof. As for the electrode of the light-emitting device described in item 1 of the scope of patent application, the mixing weight ratio of the doped metal and the alkali metal salt is between 2:1 and 1:5, and the doped metal The mixing weight ratio with the metal oxide is between 2:1 and 1:5. The electrode of the light-emitting device according to the first item of the scope of patent application, wherein the thickness of the first electrode is less than or equal to 30 nm, and the thickness of the auxiliary electrode is between 300 nm and 500 nm. The electrode of the light-emitting device according to the first item of the scope of patent application, wherein the auxiliary electrode is in direct contact with the first electrode. The electrode of the light-emitting device according to the first item of the patent application, further comprising a metal layer, wherein the metal layer is located between the first electrode and the auxiliary electrode, and the thickness of the metal layer is between 5 nm and 10 nm . A light emitting device includes: Substrate The active component layer is arranged on the substrate; An insulating layer disposed on the substrate and the active device layer; The pixel definition layer is arranged on part of the insulating layer; The light-emitting element is disposed on the insulating layer and includes a first electrode, a light-emitting layer, and a second electrode, wherein the second electrode is disposed on the insulating layer and located between the insulating layer and the pixel definition layer And electrically connected to the active device layer, and the light-emitting layer is located between the second electrode and the first electrode; An auxiliary electrode disposed on part of the first electrode and covering the active device layer; and A thin film encapsulation layer covering the light emitting element and the auxiliary electrode; The material of the first electrode is metal oxide or alkali metal salt doped with metal, and the material of the auxiliary electrode includes metal or its alloy. The light-emitting device according to claim 9, wherein the metal oxide includes LiO ₂ (lithium superoxide) or MoO ₃ (molybdenum trioxide) and the alkali metal salt includes LiF (lithium fluoride), LiBO ₃ (lithium borate), K ₂ SiO ₃ (potassium silicate), Cs ₂ CO ₃ (cesium carbonate) or CH ₃ COOM (acetate), M is Li (lithium), Na (sodium), K (potassium) , Rb (rubidium) or Cs (cesium). The light-emitting device according to claim 9, wherein the metal doped in the first electrode includes Al (aluminum), Ca (calcium), Ag (silver), Cu (copper), Mg (magnesium) ) Or its alloys. The light-emitting device according to item 9 of the scope of patent application, wherein the mixing weight ratio of the doped metal and the alkali metal salt is between 2:1 and 1:5, and the doped metal and the The mixing weight ratio of the metal oxides is between 2:1 and 1:5. According to the light-emitting device described in item 9 of the scope of patent application, the thickness of the first electrode is less than or equal to 30 nm, and the thickness of the auxiliary electrode is between 300 nm and 500 nm. The light-emitting device according to the ninth patent application, wherein the auxiliary electrode is in direct contact with the first electrode. The light-emitting device described in item 9 of the scope of patent application further includes a metal layer, wherein the metal layer is located between the first electrode and the auxiliary electrode, and the thickness of the metal layer is between 5 nm and 10 nm. The light-emitting device according to the 15th patent application, wherein the metal layer includes Ag (silver) or Au (gold). The light-emitting device according to item 15 of the scope of the patent application further includes an optical matching layer, wherein the optical matching layer is conformally formed on the auxiliary electrode. The light-emitting device described in item 9 of the scope of patent application further includes a metal oxide layer, wherein the metal oxide layer is located between the first electrode and the auxiliary electrode. The light-emitting device described in item 18 of the scope of patent application further includes an alienation layer, wherein the alienation layer is disposed on the metal oxide layer exposed by the auxiliary electrode. The light-emitting device according to item 9 of the scope of patent application, wherein the light-emitting device has a light-transmitting area and a non-light-transmitting area, the light-emitting layer is located in the light-transmitting area, and the auxiliary electrode is located in the non-light-transmitting area .

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