Display panel and its manufacturing method, display device

Abstract

The present invention discloses a display panel, a manufacturing method thereof, and a display device, the display panel including a substrate, an organic planarization layer, an anode, a light-emitting layer, and a cathode, which are sequentially provided, the anode including a hydrogen barrier layer, a reflective layer, and an electrode layer, which are sequentially provided on the organic planarization layer, the reducibility of a metal in the reflective layer is greater than the reducibility of hydrogen gas, the material of the hydrogen barrier layer is a metal or an alloy, and the reducibility of the metal in the hydrogen barrier layer is less than the reducibility of hydrogen gas.

Description

[Technical field]

[0001] The present invention relates to the technical field of displays, and more particularly to a display panel, a manufacturing method thereof, and a display device. [Background technology]

[0002] In top-emission type active matrix organic light emitting diode (AMOLED) display products, a planarization layer is usually provided between the thin film transistor and the anode to improve the flatness of the entire film layer. However, since the planarization layer is made of an organic material, it absorbs water vapor generated from the external environment and during product manufacturing, and a small amount of water vapor remains inside the planarization layer.

[0003] In conventional top-emission AMOLED display panels, the anode is usually a laminated structure of a reflective film and an electrode layer. The reflective film is located on the side of the electrode layer closer to the planarization layer, and the material of the reflective film is generally a metal with high reflectivity. Metals such as aluminum used in the reflective film material are highly active, so that the planarization layer and the reflective film come into direct contact with each other during the high-temperature manufacturing process of the electrode layer deposition method, thereby ionizing the water in the planarization layer to generate hydrogen ions. When the hydrogen ions diffuse into the channel of the oxide semiconductor layer along the direction approaching the thin film transistor, they turn the channel into a conductor, causing serious negative drift in the electrical characteristics of the thin film transistor and reducing the electrical stability of the thin film transistor. Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE DISCLOSURE The present invention provides a display panel and a manufacturing method thereof, and a display device, for improving the electrical stability of a thin film transistor. [Means for solving the problem]

[0005] An embodiment of the present invention comprises: A substrate; a metal oxide thin film transistor provided on the substrate; an organic planarization layer provided on a side of the metal oxide thin film transistor away from the substrate, the organic planarization layer having a via hole provided therein; an anode provided on a side of the organic planarization layer away from the metal oxide thin film transistor, covering the via hole and connected to the metal oxide thin film transistor; a light-emitting layer provided on the anode side away from the organic planarization layer; a cathode provided on a side of the light-emitting layer farther from the anode, The anode includes a hydrogen barrier layer, a reflective layer, and an electrode layer, which are sequentially provided on the organic planarization layer, and the reduction of the metal in the reflective layer is greater than the reduction of hydrogen gas, the material of the hydrogen barrier layer is a metal or an alloy, and the reduction of the metal in the hydrogen barrier layer is less than the reduction of hydrogen gas.

[0006] Optionally, in some embodiments of the present invention, the metal in the hydrogen barrier layer comprises at least one of Mo, Ti, and Ni.

[0007] Optionally, in some embodiments of the present invention, the material of the hydrogen barrier layer comprises a Mo / Ti alloy, a Mo / Ni alloy, or a Mo / Ti / Ni alloy.

[0008] Optionally, in some embodiments of the present invention, the metal in the reflective layer comprises Al.

[0009] Optionally, in some embodiments of the present invention, the metal in the reflective layer further comprises at least one of Ni, Cu, and La.

[0010] Optionally, in some embodiments of the present invention, a material of the reflective layer comprises an Al / Ni / Cu / La alloy and a material of the hydrogen barrier layer comprises a Mo / Ni / Ti alloy.

[0011] Optionally, in some embodiments of the present invention, the display panel further includes: a passivation layer disposed between the metal oxide thin film transistor and the organic planarization layer, with a first connection hole disposed therein; and a first guard electrode disposed between the passivation layer and the organic planarization layer, covering the first connection hole and connected to the anode and the metal oxide thin film transistor, respectively.

[0012] Optionally, in some embodiments of the present invention, the metal oxide thin film transistor comprises an oxide semiconductor layer, a gate insulating layer, a gate and a source drain, sequentially disposed on the substrate, and the display panel further comprises a dielectric insulating layer disposed between the gate and the source drain and in contact with a surface of the gate and a surface of the source drain, respectively.

[0013] An embodiment of the present invention provides a display device including a housing and a display panel provided in the housing, the display panel being the display panel described in any of the above-described embodiments.

[0014] An embodiment of the present invention comprises: Providing a substrate; forming a metal oxide thin film transistor on one side of the substrate; forming an organic planarization layer on the metal oxide thin film transistor, the organic planarization layer having a via hole formed therein; a step of sequentially forming a hydrogen barrier substrate layer, a reflective substrate layer and an electrode substrate layer on the organic planarization layer, in which the reducibility of a metal in the reflective substrate layer is greater than the reducibility of hydrogen gas, and the material of the hydrogen barrier substrate layer is a metal or an alloy, and the reducibility of the metal in the hydrogen barrier substrate layer is less than the reducibility of hydrogen gas; annealing the hydrogen barrier substrate layer, the reflective substrate layer, and the electrode substrate layer; patterning the hydrogen barrier substrate layer, the reflective substrate layer and the electrode substrate layer to form a hydrogen barrier layer from the hydrogen barrier substrate layer, a reflective layer from the reflective substrate layer, and an electrode layer from the electrode substrate layer, the hydrogen barrier layer, the reflective layer and the electrode layer constituting an anode, the anode covering the via hole and connected to the metal oxide thin film transistor; sequentially forming a light emitting layer and a cathode on the anode.

[0015] Optionally, in some embodiments of the present invention, a material of the reflective substrate layer comprises an Al / Ni / Cu / La alloy and a material of the hydrogen barrier substrate layer comprises a Mo / Ni / Ti alloy, and the step of patterning the hydrogen barrier substrate layer, the reflective substrate layer and the electrode substrate layer comprises: Etching the electrode base material layer by a dry etching method to form the electrode layer; Etching the reflective substrate layer and the hydrogen barrier substrate layer by the same wet etching process to form the reflective layer and the hydrogen barrier layer, respectively. Effect of the Invention

[0016] Compared with display panels in the prior art, the display panel of the present invention has a hydrogen barrier layer between an organic planarization layer and a reflective layer, and the reducing property of the metal in the hydrogen barrier layer is less than that of hydrogen gas, and the activity of the metal in the hydrogen barrier layer is weaker than that of a highly active metal whose reducing property is greater than that of hydrogen gas. Therefore, in the high-temperature manufacturing process in the film formation method of the electrode layer, water in the organic planarization layer cannot be ionized to generate hydrogen ions, and the hydrogen ions are prevented from diffusing into the channel, preventing the channel from becoming a conductor, reducing the probability of negative drift in the electrical characteristics of the thin film transistor, and improving the electrical stability of the thin film transistor. [Brief description of the drawings]

[0017] In order to more clearly describe the technical means in the embodiments of the present invention, the following briefly introduces the drawings that need to be used in the description of the embodiments, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and those skilled in the art can also derive other drawings from these drawings without creative efforts. [Figure 1] FIG. 1 is a schematic diagram showing the structure of a display panel in the prior art. [Diagram 2] FIG. 2 is a structural schematic diagram of a display panel according to an embodiment of the present invention. [Diagram 3] FIG. 3 is a flowchart showing a method for manufacturing a display panel according to the present invention. [Figure 4A] 4A to 4I are schematic diagrams of structures obtained sequentially in each step in the manufacturing method of the display panel shown in FIG. [Figure 4B] 4A to 4I are schematic diagrams of structures obtained sequentially in each step in the manufacturing method of the display panel shown in FIG. [Figure 4C] 4A to 4I are schematic diagrams of structures obtained sequentially in each step in the manufacturing method of the display panel shown in FIG. [Figure 4D] 4A to 4I are schematic diagrams of structures obtained sequentially in each step in the manufacturing method of the display panel shown in FIG. [Figure 4E] 4A to 4I are schematic diagrams of structures obtained sequentially in each step in the manufacturing method of the display panel shown in FIG. [Figure 4F] 4A to 4I are schematic diagrams of structures obtained sequentially in each step in the manufacturing method of the display panel shown in FIG. [Figure 4G] 4A to 4I are schematic diagrams of structures obtained sequentially in each step in the manufacturing method of the display panel shown in FIG. [Figure 4H] 4A to 4I are schematic diagrams of structures obtained sequentially in each step in the manufacturing method of the display panel shown in FIG. [Figure 4I] 4A to 4I are schematic diagrams of structures obtained sequentially in each step in the manufacturing method of the display panel shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, the technical means in the embodiments of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention, but it is clear that the described embodiments are not all of the embodiments of the present invention, but are merely some of the embodiments. All other embodiments obtained by those skilled in the art without creative efforts based on the embodiments of the present invention belong to the protection scope of the present invention. In addition, it should be understood that the specific embodiments described herein are for explaining and interpreting the present invention, and are not intended to limit the present invention. In the present invention, unless otherwise stated, the directional terms used, such as "upper" and "lower", usually mean the upper and lower in the state in which the device is actually used or in operation, specifically the drawing direction in the attached drawings, while "inner" and "outer" refer to the outline of the device.

[0019] As shown in FIG. 1, in the prior art organic light-emitting diode display panel 100', the anode 10' has a laminated structure of a reflective film 11' and an electrode layer 12'. The material of the reflective film 11' is an active metal having high reflectivity, for example, aluminum or an alloy containing an active metal, and the material of the electrode layer 12' is a metal oxide. Specifically, the manufacturing method of the anode 10' includes first forming a reflective film and a metal layer on the entire surface, then performing a high-temperature annealing treatment in an oxygen atmosphere to oxidize the metal in the metal layer to form a metal oxide, and using the metal oxide as the electrode material of the anode 10', and finally forming a patterned reflective film 11' and a patterned electrode layer 12' by patterning. However, under the above-mentioned high temperature conditions, the planarization layer 20' and the reflective film 11' come into direct contact with each other, ionizing the water in the planarization layer 20' to generate hydrogen ions, and by providing dense aluminum oxide layers 40' on the upper and lower surfaces of the dielectric insulating layer 30', respectively, the hydrogen ions in the planarization layer 20' are prevented from diffusing into the oxide semiconductor layer 50', effectively protecting the channel 51' and preventing the channel 51' from becoming conductive.

[0020] However, the inventors of the present invention have found through implementation and consideration of the above design that the configuration of aluminum oxide layer 40' has the following technical problems: first, the provision of aluminum oxide layer 40' adds a new manufacturing process, thereby increasing manufacturing costs. For example, since physical vapor deposition must be used to form aluminum oxide layer 40', the use of a physical vapor deposition apparatus significantly increases equipment costs; second, the raw material used in the aluminum oxide film formation process is an aluminum oxide target, and since aluminum particles are present in the aluminum oxide target, foreign matter is present in the system during the film formation process, and further black spots are generated on the display panel, resulting in a decrease in the manufacturing yield of the product; and third, since the openings in dielectric insulating layer 30' are formed by an etching method, the provision of aluminum oxide layer 40' requires re-adjusting process parameters in the above etching method, thereby increasing the burden on production capacity.

[0021] In view of the above-mentioned technical problems existing in the prior art, the present invention provides a display panel, a manufacturing method thereof, and a display device, each of which will be described in detail below.

[0022] The present invention provides a display panel comprising a substrate, a metal oxide thin film transistor, an organic planarization layer, an anode, a light-emitting layer and a cathode. The metal oxide thin film transistor is provided on a substrate. The organic planarization layer is provided on a side of the metal oxide thin film transistor remote from the substrate. A via hole is provided in the organic planarization layer. An anode is provided on a side of the organic planarization layer remote from the metal oxide thin film transistor. The anode covers the via hole and is connected to the metal oxide thin film transistor. An emitting layer is provided on a side of the anode remote from the organic planarization layer. A cathode is provided on a side of the emitting layer remote from the anode. The anode comprises a hydrogen barrier layer, a reflective layer and an electrode layer sequentially provided on the organic planarization layer. The reducing ability of the metal in the reflective layer is greater than the reducing ability of hydrogen gas. The material of the hydrogen barrier layer is a metal or an alloy, and the reducing ability of the metal in the hydrogen barrier layer is less than the reducing ability of hydrogen gas.

[0023] Therefore, in the display panel of the present invention, a hydrogen barrier layer is provided between the organic planarization layer and the reflective layer, and the reducing property of the metal in the hydrogen barrier layer is less than that of hydrogen gas, and the activity of the metal in the hydrogen barrier layer is weaker than that of a highly active metal whose reducing property is greater than that of hydrogen gas. Therefore, in the high-temperature manufacturing process in the film formation method of the electrode layer, water in the organic planarization layer cannot be ionized to generate hydrogen ions, and further, the hydrogen ions are prevented from diffusing into the channel, preventing the channel from becoming a conductor, reducing the probability of negative drift in the electrical characteristics of the thin film transistor, and improving the electrical stability of the thin film transistor.

[0024] The display panel according to the present invention will be described in detail below with reference to specific embodiments.

[0025] As shown in FIG. 2, an embodiment of the present invention provides a display panel 100, which includes a substrate 10, a light-shielding electrode 11, a buffer layer 12, a metal oxide thin film transistor 13, a dielectric insulating layer 14, a passivation layer 15, a first guard electrode 16, an organic planarization layer 17, an anode 18, a pixel defining layer 19, a light-emitting layer 20 and a cathode 21.

[0026] The substrate 10 may be a hard substrate such as a glass substrate, or may be a flexible substrate such as a polyimide substrate, and the present invention does not particularly limit the material of the substrate 10.

[0027] The light-shielding electrode 11 is provided on one side of the substrate 10. The material of the light-shielding electrode 11 may be Mo, Ti, Cu or Mn, or may be an alloy made of at least two of these metals.

[0028] The buffer layer 12 is provided on the side of the light-shielding electrode 11 farther from the substrate 10, and may have a single-layer structure, a two-layer structure, or a multi-layer structure. The material of the buffer layer 12 may include one or more of silicon oxide, silicon nitride, and silicon oxynitride. For example, when the buffer layer 12 has a two-layer structure, the two-layer structure may include a bottom layer having silicon oxide as an insulating material and a top layer having silicon nitride as an insulating material.

[0029] The metal oxide thin film transistor 13 is provided on the side of the buffer layer 12 farther from the light-shielding electrode 11, and includes an oxide semiconductor layer 131, a gate insulating layer 132, a gate 133, and a source / drain .

[0030] In addition, the metal oxide thin film transistor 13 in the present invention may be a top gate type structure or a bottom gate type structure. In this embodiment, the metal oxide thin film transistor 13 having a top gate type structure is described as an example, but it should not be understood as limiting the present invention.

[0031] The oxide semiconductor layer 131 is provided on the buffer layer 12, and includes a channel 1311 and conductive portions 1312 provided on both opposing sides of the channel 1311. The material of the oxide semiconductor layer 131 includes one or more metal oxides selected from IGZO, IGTO, IZTO, IGZTO, ITO, and IZO. In this embodiment, the material of the oxide semiconductor layer 131 is IGZO.

[0032] The gate insulating layer 132 is provided on the side of the oxide semiconductor layer 131 farther from the buffer layer 12. The material of the gate insulating layer 132 may include one or more of silicon oxide, silicon nitride, and silicon oxynitride. For example, when the gate insulating layer 132 has a two-layer structure, the two-layer structure may include a bottom layer having silicon oxide as an insulating material and a top layer having silicon nitride as an insulating material.

[0033] The gate 133 is provided on the side of the gate insulating layer 132 farther from the oxide semiconductor layer 131, and may have a single-layer structure, a two-layer structure, or a multi-layer structure. The material of the gate 133 may include one or more of Cu, Al, Mo, and Ti. For example, when the gate 133 has a two-layer structure, the two-layer structure may include a bottom layer having Mo as a conductive material and a top layer having Cu as a conductive material.

[0034] The source drain 134 is provided on the side of the gate 133 farther from the gate insulating layer 132, and includes a source 1341 connected to the conductive portion 1312 on one side of the channel 1311, and a drain 1342 connected to the conductive portion 1312 on the other side of the channel 1311. Specifically, the source drain 134 may have a single-layer structure, a two-layer structure, or a multi-layer structure. The material of the source drain 134 may include one or more of Cu, Al, Mo, and Ti. For example, when the source drain 134 has a two-layer structure, the two-layer structure may include a bottom layer made of Mo as a conductive material and a top layer made of Cu as a conductive material.

[0035] In this embodiment, the display panel 100 further includes a bonding pad 134a provided in the same layer as the source / drain 134 and spaced apart from each other. The bonding pad 134a is provided in a bonding region (not shown) and is a conventional technique, so a description thereof will be omitted here.

[0036] Furthermore, in this embodiment, the display panel 100 further includes a first conductive portion 11a that is in the same layer as the light-shielding electrode 11 and is provided at an interval, and a second conductive portion 131a that is in the same layer as the oxide semiconductor layer 131 and is provided at an interval. An orthogonal projection of the first conductive portion 11a onto a plane on the substrate 10 and an orthogonal projection of the second conductive portion 131a onto a plane on the substrate 10 at least partially overlap each other so as to form a capacitance between the first conductive portion 11a and the second conductive portion 131a. In order to save manufacturing costs, the first conductive portion 11a and the light-shielding electrode 11 are manufactured and obtained by the same process, and the second conductive portion 131a and the oxide semiconductor layer 131 are manufactured and obtained by the same process.

[0037] The dielectric insulating layer 14 is provided between the gate 133 and the source drain 134. The material of the dielectric insulating layer 14 can include one or more of silicon oxide, silicon nitride, or silicon oxynitride. For example, when the dielectric insulating layer 14 has a two-layer structure, the two-layer structure can include a bottom layer having silicon oxide as an insulating material and a top layer having silicon nitride as an insulating material.

[0038] The passivation layer 15 is provided on the side of the source-drain layer 134 farther from the dielectric insulating layer 14, and has a first connection hole 151 exposing the drain 1342 and a second connection hole 152 exposing the bonding pad 134a provided therein, and may have a single-layer structure, a two-layer structure, or a multi-layer structure. The material of the passivation layer 15 may include one or more of silicon oxide, silicon nitride, and silicon oxynitride. For example, when the passivation layer 15 has a two-layer structure, the two-layer structure may include a bottom layer having silicon oxide as an insulating material and a top layer having silicon nitride as an insulating material.

[0039] The first guard electrode 16 is provided on the side of the passivation layer 15 farther from the source-drain 134, covers the first connection hole 151, and is connected to the drain 1342. In this embodiment, the material of the first guard electrode 16 may be a metal with excellent corrosion resistance, such as Ti. The display panel 100 further includes a second guard electrode 16a that is provided in the same layer as the first guard electrode 16, spaced apart from it, and formed by the same process. The second guard electrode 16a extends into the second connection hole 152, and is connected to the bonding pad 134a.

[0040] The organic planarization layer 17 is provided on the side of the metal protective layer farther from the passivation layer 15, and has a via hole 171 therein that communicates with the first connection hole 151. The material of the organic planarization layer 17 may be an organic material such as an acrylic resin or an epoxy resin.

[0041] The anode 18 is provided on the side of the organic planarization layer 17 away from the metal protective layer, extends into the via hole 171, and is connected to the first guard electrode 16. The anode 18 includes a hydrogen barrier layer 181, a reflective layer 182, and an electrode layer 183, which are provided in that order on the organic planarization layer 17.

[0042] In this embodiment, the material of the hydrogen barrier layer 181 is a metal or an alloy. The reducibility of the metal in the hydrogen barrier layer 181 is less than that of hydrogen gas. Specifically, when the material of the hydrogen barrier layer 181 is a metal, the reducibility of the metal is less than that of hydrogen gas, and when the material of the hydrogen barrier layer 181 is an alloy, the reducibility of at least one metal in the alloy is less than that of hydrogen gas.

[0043] With the above-mentioned configuration, the activity of the metal in the hydrogen barrier layer 181 is weaker than that of highly active metals whose reducing ability is greater than that of hydrogen gas, and even under high temperature conditions, contact between the hydrogen barrier layer 181 and the organic planarization layer 17 does not ionize the water in the organic planarization layer 17 to form hydrogen ions, thereby preventing the hydrogen ions from diffusing into the channel 1311 and preventing the channel 1311 from becoming a conductor, reducing the probability of negative drift occurring in the electrical characteristics of the metal oxide thin film transistor 13, and improving the electrical stability of the metal oxide thin film transistor 13.

[0044] In the present invention, the activity of a metal is relative; that is, based on the relative magnitude of the reducibility of a metal to that of hydrogen gas, if the reducibility of a metal is greater than that of hydrogen gas, the metal has strong activity, and if the reducibility of a metal is less than that of hydrogen gas, the metal has weak reducing activity.

[0045] The metal in the hydrogen barrier layer 181 may include at least one of Mo, Ti, and Ni. In some specific embodiments, the material of the hydrogen barrier layer 181 may be a metal, such as Mo, Ti, or Ni. Also, in some specific embodiments, the material of the hydrogen barrier layer 181 may be an alloy, such as a Mo / Ti alloy, a Mo / Ni alloy, or a Mo / Ti / Ni alloy. In this embodiment, the material of the hydrogen barrier layer 181 is a Mo / Ti / Ni alloy.

[0046] Furthermore, the thickness of the hydrogen barrier layer 181 may be 300 angstroms to 2000 angstroms. When the thickness is within the above range, the hydrogen barrier layer 181 has an excellent hydrogen barrier effect and can maintain good electrical conductivity with the reflective layer 182. In some specific embodiments, the thickness of the hydrogen barrier layer 181 may be 300 angstroms, 500 angstroms, 800 angstroms, 1000 angstroms, 1200 angstroms, 1500 angstroms, 1800 angstroms, or 2000 angstroms.

[0047] The material of the reflective layer 182 may be a metal or an alloy. When the material of the reflective layer 182 is a metal, the reducibility of the metal is greater than that of hydrogen gas, and when the material of the reflective layer 182 is an alloy, the reducibility of the metal in the alloy is greater than that of hydrogen gas. Specifically, the metal in the reflective layer 182 includes Al. Furthermore, the metal in the reflective layer 182 may further include at least one of Ni, Cu, and La. In this embodiment, the material of the reflective layer 182 is an Al / Ni / Cu / La alloy.

[0048] The material of the electrode layer 183 may be a transparent metal oxide, such as indium tin oxide, indium zinc oxide or tungsten oxide. In this embodiment, the material of the electrode layer 183 is tungsten oxide, so that the electrode layer 183 has an improved ability to excite electrons.

[0049] The inventors of the present invention have found through testing that in a panel structure in which the hydrogen barrier layer 181 is not provided, such as the organic light-emitting diode display panel 100' in FIG. 1, the electrical stability of the thin film transistor is low, that is, the negative bias of the threshold voltage of the thin film transistor is serious, and the negative bias value of the threshold voltage reaches 5V to 9V. In contrast, in this embodiment, by providing the hydrogen barrier layer 181, the negative bias value of the threshold voltage of the metal oxide thin film transistor 13 can be reduced to 1V. Thus, in this embodiment, by providing the hydrogen barrier layer 181, the negative bias value of the threshold voltage of the thin film transistor can be significantly reduced, the probability of electrical negative drift of the thin film transistor can be reduced, and the electrical stability of the thin film transistor can be improved.

[0050] In this embodiment, the dielectric insulating layer 14 is provided between the gate 133 and the source drain 134, and contacts the surface of the gate 133 and the surface of the source drain 134, respectively. By providing the hydrogen barrier layer 181, it is possible to prevent the generation of hydrogen ions in the organic planarization layer 17, that is, to effectively prevent the diffusion of hydrogen ions to the channel 1311, so that in this embodiment, it is not necessary to provide an additional aluminum oxide layer 40' on the surface of the dielectric insulating layer 14 to protect the channel 1311. Therefore, compared with the configuration in which the aluminum oxide layers 40' are provided on the upper and lower surfaces of the dielectric insulating layer 14 in the conventional technology, the display panel 100 according to this embodiment has the following advantages: first, it is possible to reduce the equipment cost required for manufacturing the aluminum oxide layer 40'; second, it is possible to prevent the loss of product yield due to the presence of foreign matter during the film formation process of the aluminum oxide layer 40', thereby improving the product yield; and third, it is not necessary to adjust the process parameters in the etching method for the dielectric insulating layer 14, thereby reducing the burden on production capacity.

[0051] The pixel definition layer 19 is provided on the side of the anode 18 farther from the organic planarization layer 17, and has an opening 191 therein for exposing the anode 18. The light-emitting layer 20 is provided in the opening 191. The cathode 21 is provided on the side of the light-emitting layer 20 farther from the anode 18. Note that the specific configurations and materials of the pixel definition layer 19, the light-emitting layer 20, and the cathode 21 can be referred to in the prior art, and therefore will not be described here.

[0052] The present invention further provides a display device which is a display product such as a mobile phone, a tablet, a notebook computer, a television, etc. The display device includes a housing and a display panel provided in the housing, and the display panel may be the display panel 100 according to the above-mentioned embodiment. The specific configuration of the display panel 100 can be referred to the description of the above-mentioned embodiment, and the description will be omitted here.

[0053] As shown in FIG. 3, the present invention further provides a method for manufacturing a display panel, including steps 101 to 107, Step 101, a substrate is provided. Step 102, a metal oxide thin film transistor is formed on one side of a substrate. Step 103, forming an organic planarization layer on the metal oxide thin film transistor, the organic planarization layer having a via hole formed therein. Step 104: sequentially forming a hydrogen barrier substrate layer, a reflective substrate layer and an electrode substrate layer on the organic planarization layer, in which the reducibility of the metal in the reflective substrate layer is greater than that of hydrogen gas, the material of the hydrogen barrier substrate layer is a metal or an alloy, and the reducibility of the metal in the hydrogen barrier substrate layer is less than that of hydrogen gas. Step 105, anneal the hydrogen barrier substrate layer, the reflective substrate layer and the electrode substrate layer. Step 106: patterning the hydrogen barrier substrate layer, the reflective substrate layer and the electrode substrate layer to form a hydrogen barrier layer from the hydrogen barrier substrate layer, a reflective layer from the reflective substrate layer, and an electrode layer from the electrode substrate layer, in which the hydrogen barrier layer, the reflective layer and the electrode layer constitute an anode, which covers the via hole and is connected to the metal oxide thin film transistor. Step 107: forming a light-emitting layer and a cathode on the anode in sequence.

[0054] Therefore, in the manufacturing method of the display panel of the present invention, a hydrogen barrier layer is provided between the organic planarization layer and the reflective layer, and the reducing property of the metal in the hydrogen barrier layer is less than that of hydrogen gas, and the activity of the metal in the hydrogen barrier layer is weaker than that of a highly active metal whose reducing property is greater than that of hydrogen gas. Therefore, under the high temperature conditions during the annealing treatment, the water in the organic planarization layer cannot be ionized to generate hydrogen ions, and further, the hydrogen ions are prevented from diffusing into the channel, preventing the channel from becoming a conductor, reducing the probability of negative drift in the electrical characteristics of the thin film transistor, and improving the electrical stability of the thin film transistor.

[0055] 3 and 4A to 4I, a method for manufacturing the display panel 100 according to the present invention will be described in detail below with reference to specific embodiments. The method for manufacturing the display panel 100 according to the present invention includes steps 101 to 107.

[0056] Step 101, as shown in FIG. 4A, a substrate 10 is provided.

[0057] The substrate 10 may be a hard substrate such as a glass substrate, or may be a flexible substrate such as a polyimide substrate, and the material of the substrate 10 is not particularly limited in the present invention.

[0058] Step 102, as shown in FIG. 4B, a metal oxide thin film transistor 13 is formed on one side of the substrate 10.

[0059] Specifically, the metal oxide thin film transistor 13 is formed on the substrate 10 and includes an oxide semiconductor layer 131, a gate insulating layer 132, a gate 133, and a source drain 134, which are formed in this order. The oxide semiconductor layer 131 includes a channel 1311 and conductive portions 1312 provided on both opposing sides of the channel 1311. The source drain 134 includes a source 1341 connected to the conductive portion 1312 on one side of the channel 1311, and a drain 1342 connected to the conductive portion 1312 on the other side of the channel 1311.

[0060] In this embodiment, a dielectric insulating layer 14 is formed between the gate 133 and the source / drain 134, in contact with the surface of the gate 133 and the surface of the source / drain 134, respectively. In addition, at the same time as forming the source / drain 134, a bonding pad 134a located in the bonding region is formed.

[0061] Between steps 101 and 102, the method for manufacturing the display panel 100 further includes the step of sequentially forming a light-shielding electrode 11, a first conductive portion 11a, and a buffer layer 12 on the substrate 10, but the description thereof will be omitted here.

[0062] Step 103: forming an organic planarization layer 17 on the metal oxide thin film transistor 13, the organic planarization layer 17 having a via hole 171 formed therein;

[0063] As shown in FIG. 4C to FIG. 4E, step 103 specifically includes sequentially forming a passivation layer 15, a first guard electrode 16, a second guard electrode 16a, and an organic planarization layer 17 on the metal oxide thin film transistor 13. As shown in FIG. 4C, the passivation layer 15 is formed with a first connection hole 151 exposing the drain 1342 and a second connection hole 152 exposing the bonding pad 134a. As shown in FIG. 4D, the first guard electrode 16 covers the first connection hole 151 and is connected to the drain 1342, and the second guard electrode 16a extends into the second connection hole 152 and is connected to the bonding pad 134a. As shown in FIG. 4E, a via hole 171 communicating with the first connection hole 151 is provided in the organic planarization layer 17.

[0064] In step 104, as shown in FIG. 4F , a hydrogen barrier substrate layer 181a, a reflective substrate layer 182a, and an electrode substrate layer 183a are sequentially formed on the organic planarization layer 17, such that the reducing property of the metal in the reflective substrate layer 182a is greater than the reducing property of hydrogen gas, the material of the hydrogen barrier substrate layer 181a is a metal or an alloy, and the reducing property of the metal in the hydrogen barrier substrate layer 181a is less than the reducing property of hydrogen gas.

[0065] In this embodiment, the material of the hydrogen barrier substrate layer 181a is a metal or an alloy, and specifically, the hydrogen barrier substrate layer 181a can be formed by physical vapor deposition. The reduction of the metal in the hydrogen barrier substrate layer 181a is less than that of hydrogen gas. Specifically, when the material of the hydrogen barrier substrate layer 181a is a metal, the reduction of the metal is less than that of hydrogen gas, and when the material of the hydrogen barrier substrate layer 181a is an alloy, the reduction of at least one metal in the alloy is less than that of hydrogen gas.

[0066] The metal in the hydrogen barrier substrate layer 181a may include at least one of Mo, Ti, and Ni. In some specific embodiments, the material of the hydrogen barrier substrate layer 181a may be a metal such as Mo, Ti, or Ni. In some specific embodiments, the material of the hydrogen barrier substrate layer 181a may be an alloy such as a Mo / Ti alloy, a Mo / Ni alloy, or a Mo / Ti / Ni alloy. In this embodiment, the material of the hydrogen barrier substrate layer 181a is a Mo / Ti / Ni alloy.

[0067] Furthermore, the hydrogen barrier substrate layer 181a may have a thickness of 300 Å to 2000 Å. In some specific embodiments, the hydrogen barrier substrate layer 181a may have a thickness of 300 Å, 500 Å, 800 Å, 1000 Å, 1200 Å, 1500 Å, 1800 Å, or 2000 Å.

[0068] The material of the reflective substrate layer 182a may be a metal or an alloy, and specifically, the reflective substrate layer 182a can be formed by physical vapor deposition. When the material of the reflective substrate layer 182a is a metal, the reducibility of the metal is greater than that of hydrogen gas, and when the material of the reflective substrate layer 182a is an alloy, the reducibility of the metal in the alloy is greater than that of hydrogen gas. Specifically, the metal in the reflective substrate layer 182a includes Al. Furthermore, the metal in the reflective substrate layer 182a can further include at least one of Ni, Cu, and La. In this embodiment, the material of the reflective substrate layer 182a is an Al / Ni / Cu / La alloy.

[0069] The material of the electrode substrate layer 183a may be indium tin oxide or tungsten, and specifically, the electrode substrate layer 183a can be formed by physical vapor deposition. In this embodiment, the material of the electrode substrate layer 183a is tungsten.

[0070] In step 105, the hydrogen barrier substrate layer 181a, the reflective substrate layer 182a and the electrode substrate layer 183a are annealed as shown in FIG. 4F.

[0071] Specifically, the chamber in which the hydrogen barrier substrate layer 181a, the reflective substrate layer 182a, and the electrode substrate layer 183a are located is annealed in an oxygen atmosphere so that the tungsten in the electrode substrate layer 183a is oxidized to tungsten oxide. The materials of the hydrogen barrier substrate layer 181a and the reflective substrate layer 182a are not affected by oxygen.

[0072] In step 106, as shown in FIG. 4G , the hydrogen barrier substrate layer 181a, the reflective substrate layer 182a, and the electrode substrate layer 183a are patterned to form a hydrogen barrier layer 181 from the hydrogen barrier substrate layer 181a, a reflective layer 182 from the reflective substrate layer 182a, and an electrode layer 183 from the electrode substrate layer 183a. The hydrogen barrier layer 181, the reflective layer 182, and the electrode layer 183 constitute an anode 18, which covers the via hole 171 and is connected to the metal oxide thin film transistor 13.

[0073] Step 106 specifically includes firstly etching the electrode substrate layer 183a by a dry etching method to form the electrode layer 183, and then etching the reflective substrate layer 182a and the hydrogen barrier substrate layer 181a by the same wet etching method to respectively form the reflective layer 182 and the hydrogen barrier layer 181. In the wet etching method, the reflective substrate layer 182a and the hydrogen barrier substrate layer 181a are in the same etching solution environment, for example, both are in an aluminic acid etching solution system, so that the manufacturing process of the anode 18 can be prevented from becoming complicated.

[0074] As described above, in this embodiment, the activity of the metal in the hydrogen barrier layer 181 is weaker than that of a highly active metal whose reducing property is greater than that of hydrogen gas, and under high temperature conditions, contact between the hydrogen barrier layer 181 and the organic planarization layer 17 does not ionize the water in the organic planarization layer 17 to form hydrogen ions, thereby preventing the hydrogen ions from diffusing into the channel 1311 and preventing the channel 1311 from becoming a conductor, thereby reducing the probability of negative drift in the electrical characteristics of the metal oxide thin film transistor 13 and improving the electrical stability of the metal oxide thin film transistor 13.

[0075] The inventors of the present invention have found through testing that in a panel structure in which the hydrogen barrier layer 181 is not provided, such as the organic light-emitting diode display panel 100' in FIG. 1, the electrical stability of the thin film transistor is low, that is, the negative bias of the threshold voltage of the thin film transistor is serious, and the negative bias value of the threshold voltage reaches 5V to 9V. In contrast, in this embodiment, by providing the hydrogen barrier layer 181, the negative bias value of the threshold voltage of the metal oxide thin film transistor 13 can be reduced to 1V. Thus, in this embodiment, by providing the hydrogen barrier layer 181, the negative bias value of the threshold voltage of the thin film transistor can be significantly reduced, the probability of electrical negative drift of the thin film transistor can be reduced, and the electrical stability of the thin film transistor can be improved.

[0076] Furthermore, in this embodiment, as described in step 102, the hydrogen barrier layer 181 is provided between the organic planarization layer 17 and the reflective layer 182, so there is no need to provide an additional aluminum oxide layer 40' on the surface of the dielectric insulating layer 14 to protect the channel 1311. Therefore, compared with the configuration in which the aluminum oxide layers 40' are formed on the top and bottom surfaces of the dielectric insulating layer 14 in the conventional technology, the display panel 100 according to this embodiment has the following advantages: first, it is possible to save the equipment cost required for manufacturing the aluminum oxide layer 40'; second, it is possible to prevent the loss of product yield due to the presence of foreign matter during the film formation process of the aluminum oxide layer 40', thereby improving the product yield; and third, it is possible to reduce the burden on production capacity by not needing to adjust the process parameters in the etching method for the dielectric insulating layer 14.

[0077] After step 106, the method for manufacturing the display panel 100 further includes forming a pixel definition layer 19 on the anode 18, and the pixel definition layer 19 has an opening 191 that exposes the anode 18, as shown in FIG. 4H.

[0078] In step 107, as shown in FIG. 4I, a light-emitting layer 20 and a cathode 21 are sequentially formed on the anode 18.

[0079] The material and manufacturing method of the light-emitting layer 20 and the material and manufacturing method of the cathode 21 can be referenced from the prior art, and therefore a description thereof will be omitted here.

[0080] The display panel and the manufacturing method thereof, and the display device according to the embodiment of the present invention have been described in detail above, and the principle and the embodiment of the present invention have been described in this specification using specific embodiments. The description of the above embodiments is merely for understanding the method of the present invention and its core idea. At the same time, a person skilled in the art may make changes to the specific embodiments and the scope of application based on the concept of the present invention. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A substrate; a metal oxide thin film transistor provided on the substrate; an organic planarization layer provided on a side of the metal oxide thin film transistor away from the substrate, the organic planarization layer having a via hole provided therein; an anode provided on a side of the organic planarization layer away from the metal oxide thin film transistor, covering the via hole and connected to the metal oxide thin film transistor; a light-emitting layer provided on the anode side away from the organic planarization layer; a cathode provided on a side of the light-emitting layer farther from the anode, a display panel in which the anode includes a hydrogen barrier layer, a reflective layer, and an electrode layer, which are sequentially provided on the organic planarization layer, the reducibility of a metal in the reflective layer is greater than the reducibility of hydrogen gas, the material of the hydrogen barrier layer includes a Mo / Ti alloy, a Mo / Ni alloy, or a Mo / Ti / Ni alloy, and the reducibility of a metal in the alloy in the hydrogen barrier layer is less than the reducibility of hydrogen gas.

2. The display panel according to claim 1 , wherein the metal in the reflective layer includes Al.

3. The display panel according to claim 2 , wherein the metal in the reflective layer further includes at least one of Ni, Cu, and La.

4. A substrate, a metal oxide thin film transistor provided on the substrate; an organic planarization layer provided on a side of the metal oxide thin film transistor away from the substrate, the organic planarization layer having a via hole provided therein; an anode provided on a side of the organic planarization layer away from the metal oxide thin film transistor, covering the via hole and connected to the metal oxide thin film transistor; a light-emitting layer provided on the anode side away from the organic planarization layer; a cathode provided on a side of the light-emitting layer farther from the anode, a display panel in which the anode includes a hydrogen barrier layer, a reflective layer, and an electrode layer, which are sequentially provided on the organic planarization layer, the material of the reflective layer includes an Al / Ni / Cu / La alloy, the reducibility of the metal in the alloy in the reflective layer is greater than the reducibility of hydrogen gas, and the material of the hydrogen barrier layer includes a Mo / Ni / Ti alloy, and the reducibility of the metal in the alloy in the hydrogen barrier layer is less than the reducibility of hydrogen gas.

5. 5. The display panel of claim 4, further comprising: a passivation layer provided between the metal oxide thin film transistor and the organic planarization layer, the passivation layer having a first connection hole provided therein; and a first guard electrode provided between the passivation layer and the organic planarization layer, covering the first connection hole and connected to the anode and the metal oxide thin film transistor, respectively.

6. 6. The display panel according to claim 5, wherein the material of the first guard electrode is Ti.

7. 5. The display panel according to claim 1, wherein the hydrogen barrier layer has a thickness of 300 angstroms to 2000 angstroms.

8. 2. The display panel of claim 1, wherein when the material of the reflective layer is a metal, the reducing ability of the metal is greater than the reducing ability of hydrogen gas, and when the material of the reflective layer is an alloy, the reducing ability of the metal in the alloy is greater than the reducing ability of hydrogen gas.

9. 5. The display panel according to claim 1, wherein the metal oxide thin film transistor includes an oxide semiconductor layer, a gate insulating layer, a gate, and a source / drain, which are sequentially provided on the substrate, and the display panel further includes a dielectric insulating layer provided between the gate and the source / drain and in contact with a surface of the gate and a surface of the source / drain, respectively.

10. A display device comprising: a housing; and a display panel provided in the housing, the display panel being the display panel according to any one of claims 1 to 6.

11. Providing a substrate; forming a metal oxide thin film transistor on one side of the substrate; forming an organic planarization layer on the metal oxide thin film transistor, the organic planarization layer having a via hole formed therein; a step of sequentially forming a hydrogen barrier substrate layer, a reflective substrate layer, and an electrode substrate layer on the organic planarization layer, the step being such that the material of the reflective substrate layer includes an Al / Ni / Cu / La alloy, the reducibility of a metal in the alloy in the reflective substrate layer being greater than the reducibility of hydrogen gas, and the material of the hydrogen barrier substrate layer includes a Mo / Ni / Ti alloy, the reducibility of a metal in the alloy in the hydrogen barrier substrate layer being less than the reducibility of hydrogen gas; annealing the hydrogen barrier substrate layer, the reflective substrate layer, and the electrode substrate layer; patterning the hydrogen barrier substrate layer, the reflective substrate layer and the electrode substrate layer to form a hydrogen barrier layer from the hydrogen barrier substrate layer, a reflective layer from the reflective substrate layer, and an electrode layer from the electrode substrate layer, the hydrogen barrier layer, the reflective layer and the electrode layer constituting an anode, the anode covering the via hole and connected to the metal oxide thin film transistor; Sequentially forming a light-emitting layer and a cathode on the anode; The step of patterning the hydrogen barrier substrate layer, the reflective substrate layer, and the electrode substrate layer further comprises: Etching the electrode base material layer by a dry etching method to form the electrode layer; and etching the reflective substrate layer and the hydrogen barrier substrate layer by the same wet etching method to form the reflective layer and the hydrogen barrier layer, respectively.

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