A packaging structure

Abstract

The application discloses a packaging structure, which comprises a substrate, a light-emitting unit located on one side of the substrate, and a water-blocking layer located on the side of the light-emitting unit away from the substrate and covering the light-emitting unit; the water-blocking layer comprises at least two inorganic layers and at least one water-locking layer; the inorganic layers and the water-locking layer are alternately stacked; the water-locking layer is provided with the inorganic layer on the side close to the substrate and the side away from the substrate; the water-locking layer comprises pores; the water-locking layer is used for absorbing and locking water vapor in the packaging structure, and the inorganic layer is used for blocking water vapor. The packaging structure provided by the embodiment of the application can reduce or prevent water vapor from flowing to the inorganic layer between the water-locking layer and the light-emitting unit, and the reliability of the packaging structure is improved.

Description

Technical Field

[0001] This invention relates to the field of device packaging technology, and more particularly to a packaging structure. Background Technology

[0002] OLED (Organic Light Emitting Diodes) is a photoelectric device that emits light through carrier injection and recombination. Specifically, electrons are injected through the cathode and transported to the light-emitting layer via electron transport materials, while holes are injected through the anode and transported to the light-emitting layer via hole transport materials. Electrons and holes recombine in the light-emitting layer to form excitons, which then de-emit light.

[0003] OLEDs have garnered significant attention due to their excellent light emission uniformity, thinness, bendability, flexibility, and stretchability. However, OLEDs are extremely sensitive to water and oxygen, necessitating encapsulation. Currently, the mainstream encapsulation method is thin-film encapsulation. The structure of thin-film encapsulation is typically inorganic / organic / inorganic. The inorganic layer consists of high water-blocking materials such as alumina, titanium dioxide, silicon nitride, silicon oxynitride, and silicon oxide, while the organic materials are simple epoxy and olefin polymers. These materials lack water-blocking and water-locking properties, allowing moisture to penetrate the OLED over long periods, resulting in relatively lower reliability for thin-film encapsulation. Summary of the Invention

[0004] This invention provides an encapsulation structure that can reduce or prevent moisture from flowing to the inorganic layer between the water-locking layer and the light-emitting unit, thereby improving the reliability of the encapsulation structure.

[0005] This invention provides a packaging structure, which includes:

[0006] substrate;

[0007] The light-emitting unit is located on one side of the substrate;

[0008] A water-blocking layer is located on the side of the light-emitting unit away from the substrate and covers the light-emitting unit;

[0009] The water-blocking layer comprises at least two inorganic layers and at least one water-locking layer;

[0010] The inorganic layer and the water-locking layer are alternately stacked;

[0011] The inorganic layer is provided on both the side of the water-locking layer closest to the substrate and the side furthest from the substrate;

[0012] The water-locking layer includes pores;

[0013] The water-locking layer is used to absorb and lock in water vapor inside the encapsulation structure, and the inorganic layer is used to block water vapor.

[0014] Optionally, each of the water-locking layers includes at least two stacked water-locking sublayers;

[0015] Along the direction from the light-emitting unit to the water-blocking layer, the porosity of the water-locking sublayer decreases layer by layer.

[0016] Optionally, along the direction from the light-emitting unit to the water-blocking layer, the hydrophilicity of the water-locking sublayer increases layer by layer, and the surface energy of the water-locking sublayer increases layer by layer.

[0017] Optionally, each of the water-locking layers includes n stacked water-locking sublayers, where n ≥ 3 and n is a positive integer;

[0018] Along the direction from the light-emitting unit to the water-blocking layer, the first water-locking sublayer to the nth water-locking sublayer are arranged sequentially.

[0019] When n is a positive odd number, the gap between the first layer of water-locking sublayer and the (n+1) / 2th layer of water-locking sublayer decreases layer by layer, and the gap between the (n+1) / 2th layer of water-locking sublayer and the nth layer increases layer by layer.

[0020] When n is a positive even number, the gap between the first layer of water-locking sublayer and the second layer of water-locking sublayer decreases layer by layer, and the gap between the (n / 2)+1 layer of water-locking sublayer and the nth layer increases layer by layer.

[0021] Optionally, when n is a positive odd number, the hydrophilicity of the water-locking sublayer from the first layer to the (n+1) / 2th layer increases layer by layer, and the surface energy increases layer by layer; the hydrophilicity of the water-locking sublayer from the (n+1) / 2th layer to the nth layer decreases layer by layer, and the surface energy decreases layer by layer.

[0022] When n is a positive even number, the hydrophilicity of the water-locking sublayer from the 1st layer to the 2nd layer increases layer by layer, and the surface energy increases layer by layer. The hydrophilicity of the water-locking sublayer from the (n / 2)+1st layer to the nth layer decreases layer by layer, and the surface energy decreases layer by layer.

[0023] Optionally, the thickness of the water-locking layer includes 100 nm to 10 μm.

[0024] Optionally, the material of the water-locking layer includes at least one of biomimetic gold, urethane compounds, aldehyde compounds, olefin compounds, aromatic hydrocarbon compounds, polyester compounds, epoxy compounds, silicon oxide, silicon oxynitride, and titanium oxide.

[0025] Optionally, the pore size of the water-locking layer includes 5 nm to 10 μm.

[0026] Optionally, the water-locking layer can be formed by spin coating, slot coating, or inkjet printing.

[0027] Optionally, the material of the inorganic layer includes at least one of silicon nitride, silicon oxide, and silicon oxynitride.

[0028] This embodiment provides a packaging structure in which a water-blocking layer is located on the side of the light-emitting unit away from the substrate and covers multiple light-emitting units. The water-blocking layer includes at least two inorganic layers and at least one water-locking layer, with the inorganic layers and water-locking layers alternately stacked. The water-locking layer has inorganic layers on both the side near and away from the light-emitting unit. The inorganic layers can block external water and oxygen, while the water-locking layer has pores, allowing it to quickly absorb moisture within the packaging structure and trap it inside. This reduces or prevents moisture from flowing to the inorganic layer between the water-locking layer and the light-emitting unit, further preventing moisture erosion of the light-emitting unit. The packaging structure provided in this embodiment can reduce or prevent moisture from flowing to the inorganic layer between the water-locking layer and the light-emitting unit, improving the reliability of the packaging structure.

[0029] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of a packaging structure provided according to an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of another packaging structure provided according to an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of another packaging structure provided according to an embodiment of the present invention. Detailed Implementation

[0034] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0035] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0036] Figure 1 This is a schematic diagram of a packaging structure provided according to an embodiment of the present invention, with reference to... Figure 1 The encapsulation structure includes: a substrate 110; a light-emitting unit 120 located on one side of the substrate 110; and a water-blocking layer 130 located on the side of the light-emitting unit 120 away from the substrate 110 and covering the light-emitting unit 120. The water-blocking layer 130 includes at least two inorganic layers 131 and at least one water-locking layer 132. The inorganic layers 131 and the water-locking layer 132 are alternately stacked. The water-locking layer 132 has inorganic layers 131 on both the side close to the substrate 110 and the side away from the substrate 110. The water-locking layer 132 includes pores. The water-locking layer 132 is used to absorb and lock water vapor in the encapsulation structure, and the inorganic layers 131 are used to block water vapor.

[0037] Specifically, the substrate 110 can be a flexible substrate or a rigid substrate. When the substrate 110 is a flexible substrate, the material of the substrate 110 can be an organic polymer such as polyterephthalic acid plastic, polyimide, or polyethylene naphthalate. When the substrate 110 is a rigid substrate, the substrate 110 can be glass. The light-emitting unit 120 includes a first electrode 121, a light-emitting layer 122, and a second electrode 123 stacked sequentially. The first electrode 121 can be a cathode or an anode, and the second electrode 123 can be a cathode or an anode. When the first electrode 121 is a cathode, the second electrode 123 is an anode. The anode material includes indium tin oxide (ITO) and / or indium zinc oxide (IZO), and the cathode material includes one or more of the following metallic materials: Ag, Mg, Al, Ca, Ba, etc. The water-blocking layer 130 can include two inorganic layers 131 and one water-locking layer 132. The inorganic layer 131 can be prepared by one or a combination of atomic layer deposition, plasma-enhanced chemical vapor deposition, inkjet printing, screen printing, or sputtering. The inorganic layer 131 can block the intrusion of external water and oxygen.

[0038] The water-locking layer 132 includes pores, which allow it to quickly absorb moisture within the encapsulation structure. Porosity is a material property, and its size depends on the material type. Different materials are selected to control the pore size within the water-locking layer 132. The porous water-locking layer 132 utilizes physical properties to absorb moisture; that is, after absorbing moisture, it does not chemically react with the moisture, which remains stored as water molecules within the layer. By absorbing and trapping moisture within the encapsulation structure, the water-locking layer 132 reduces or prevents moisture from flowing to the inorganic layer 131 between the water-locking layer 132 and the light-emitting unit 120, thus preventing damage to the light-emitting unit 120 from moisture erosion.

[0039] This embodiment provides a packaging structure in which a water-blocking layer is located on the side of the light-emitting unit away from the substrate and covers the light-emitting unit. The water-blocking layer includes at least two inorganic layers and at least one water-locking layer, which are alternately stacked. Inorganic layers are disposed on both the side of the water-locking layer closest to and furthest from the light-emitting unit. The inorganic layers can block external water and oxygen, while the water-locking layer has pores, allowing it to quickly absorb moisture within the packaging structure and trap it inside. This reduces or prevents moisture from flowing to the inorganic layer between the water-locking layer and the light-emitting unit, further preventing moisture erosion of the light-emitting unit. The packaging structure provided in this embodiment can reduce or prevent moisture from flowing to the inorganic layer between the water-locking layer and the light-emitting unit, improving the reliability of the packaging structure.

[0040] Optional, Figure 2 This is a schematic diagram of another packaging structure provided according to an embodiment of the present invention, with reference to... Figure 2 Each water-locking layer 132 includes at least two stacked water-locking sub-layers 10; along the direction from the light-emitting unit 120 to the water-blocking layer 130, the pore size of the water-locking sub-layers 10 decreases layer by layer.

[0041] Specifically, when the water-locking layer 132 includes at least two stacked water-locking sub-layers 10, since each water-locking sub-layer 10 includes pores, the pore sizes of different water-locking sub-layers 10 can be set according to the capillary principle, thereby causing water vapor in the water-locking layer 132 to flow away from the light-emitting unit 120, reducing or preventing water vapor from flowing to the inorganic layer 131 between the water-locking layer 132 and the light-emitting unit 120, and further preventing water vapor from intruding into the light-emitting unit 120. The capillary principle is that water vapor can flow from areas with large pores to areas with small pores. Therefore, the pores of the water-locking sub-layers 10 can be set to gradually decrease in the direction from the light-emitting unit 120 to the water-blocking layer 130, thereby causing water vapor in the water-locking layer 132 to move away from the light-emitting unit 120.

[0042] Optionally, along the direction from the light-emitting unit to the water-blocking layer, the hydrophilicity of the water-locking sublayer increases layer by layer, and the surface energy of the water-locking sublayer increases layer by layer.

[0043] Specifically, along the direction from the light-emitting unit to the water-blocking layer, as the pore size decreases, the capillary force increases, causing water vapor to flow towards the side with smaller pores. At the same time, the surface energy increases and the hydrophilicity increases layer by layer, further providing power for the water vapor flow and accelerating the flow of water vapor away from the light-emitting unit.

[0044] Optional, Figure 3 This is a schematic diagram of another packaging structure provided according to an embodiment of the present invention, with reference to... Figure 3 Each water-locking layer 132 includes n layers of water-locking sublayers 10 stacked together, where n≥3 and n is a positive integer; along the direction from the light-emitting unit 120 to the water-blocking layer 130, the first water-locking sublayer 10 to the nth water-locking sublayer 10 are arranged sequentially; when n is a positive odd number, the gap between the first water-locking sublayer 10 and the (n+1) / 2th water-locking sublayer 10 decreases layer by layer, and the gap between the (n+1) / 2th water-locking sublayer 10 and the nth water-locking sublayer 10 increases layer by layer; when n is a positive even number, the gap between the first water-locking sublayer 10 and the n / 2th water-locking sublayer 10 decreases layer by layer, and the gap between the (n / 2)+1th water-locking sublayer 10 and the nth water-locking sublayer 10 increases layer by layer.

[0045] Specifically, based on the capillary principle, water vapor flows into the water-locking sub-layer 10 located in the middle of the water-locking layer 132. This arrangement can reduce or prevent water vapor from flowing into the inorganic layer 131 between the water-locking layer 132 and the light-emitting unit 120. The water-locking layer 132 may include 3 or 5 water-locking sub-layers 10. For example, when the water-locking layer 132 includes 3 water-locking sub-layers 10, since the pores of the second water-locking sub-layer 10 are smaller than those of the first and third water-locking sub-layers 10, water vapor in the first water-locking sub-layer 10 flows into the second water-locking sub-layer 10, and water vapor in the third water-locking sub-layer 10 also flows into the second water-locking sub-layer 10. The water vapor in the water-locking layer 132 is basically concentrated in the second water-locking sub-layer 10. The pore size of the i-th water-locking sublayer 10 can be equal to the pore size of the (n+1-i)-th water-locking sublayer 10, where n≥i≥1 and i is a positive integer.

[0046] Optionally, when n is a positive odd number, the hydrophilicity and surface energy of the first water-locking sublayer to the (n+1) / 2th water-locking sublayer increase layer by layer, while the hydrophilicity and surface energy of the (n+1) / 2th water-locking sublayer to the nth water-locking sublayer decrease layer by layer; when n is a positive even number, the hydrophilicity and surface energy of the first water-locking sublayer to the n / 2th water-locking sublayer increase layer by layer, while the hydrophilicity and surface energy of the (n / 2)+1th water-locking sublayer to the nth water-locking sublayer decrease layer by layer.

[0047] Specifically, as the pore size decreases, the capillary force increases, causing water vapor to flow towards the side with smaller pores. At the same time, the surface energy increases and the hydrophilicity increases layer by layer, further providing power for the water vapor flow and accelerating the flow of water vapor to the water-locking sublayer located in the middle of the water-locking layer.

[0048] Optionally, the thickness of the water-locking layer ranges from 100 nm to 10 μm.

[0049] Specifically, if the thickness of the water-locking layer is less than 100nm, the water absorption of the water-locking layer becomes weaker. If the thickness of the water-locking layer is greater than 10μm, the volume of the encapsulation structure will increase, and it will be difficult for the inorganic layer to adhere to the side of the water-locking layer away from the light-emitting unit. Therefore, the thickness of the water-locking layer is set to 100nm to 10μm, which can ensure the water absorption of the water-locking layer without increasing the volume of the encapsulation structure too much.

[0050] Optionally, the material of the water-locking layer includes at least one of biomimetic gold, urethane compounds, aldehyde compounds, olefin compounds, aromatic hydrocarbon compounds, polyester compounds, epoxy compounds, silicon oxide, silicon oxynitride, and titanium oxide.

[0051] Specifically, materials such as biomimetic gold, urethane compounds, aldehyde compounds, olefin compounds, aromatic hydrocarbon compounds, polyester compounds, epoxy compounds, silicon dioxide, silicon oxynitride, and titanium dioxide have pores and strong water absorption. Using these materials to make a water-locking layer can enable the water-locking layer to quickly absorb moisture inside the encapsulation structure.

[0052] Optionally, the pore size of the water-locking layer ranges from 5 nm to 10 μm.

[0053] Specifically, a pore size of 5nm to 10μm in the water-locking layer can improve its water absorption.

[0054] Optionally, the water-locking layer can be formed by spin coating, slot coating, or inkjet printing.

[0055] Specifically, the water-locking layer in this embodiment can be achieved through various methods. In actual production, a suitable method can be selected to produce the water-locking layer based on the site environment.

[0056] Optionally, the inorganic layer may be made of at least one of silicon nitride, silicon oxide, and silicon oxynitride.

[0057] Specifically, silicon nitride, silicon oxide, and silicon oxynitride can block water and oxygen, protecting the light-emitting unit from water and oxygen corrosion.

[0058] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0059] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A packaging structure, characterized in that, include: substrate; The light-emitting unit is located on one side of the substrate; A water-blocking layer is located on the side of the light-emitting unit away from the substrate and covers the light-emitting unit; The water-blocking layer comprises at least two inorganic layers and at least one water-locking layer; The inorganic layer and the water-locking layer are alternately stacked; the inorganic layer is provided on both the side of the water-locking layer closest to the substrate and the side furthest from the substrate. The water-locking layer includes pores; the pore size of the water-locking layer ranges from 5 nm to 10 μm. The water-locking layer is used to absorb and lock in water vapor inside the encapsulation structure, and the inorganic layer is used to block water vapor. Each of the aforementioned water-locking layers comprises n stacked water-locking sublayers, where n ≥ 3 and n is a positive integer; Along the direction from the light-emitting unit to the water-blocking layer, the first water-locking sublayer to the nth water-locking sublayer are arranged sequentially. When n is a positive odd number, the porosity of the water-locking sublayer from the first layer to the (n+1) / 2th layer decreases layer by layer, and the porosity of the water-locking sublayer from the (n+1) / 2th layer to the nth layer increases layer by layer. When n is a positive even number, the porosity of the water-locking sublayer from the 1st layer to the 2nd layer decreases layer by layer, and the porosity of the water-locking sublayer from the (n / 2)+1st layer to the nth layer increases layer by layer.

2. The packaging structure according to claim 1, characterized in that, Along the direction from the light-emitting unit to the water-blocking layer, the hydrophilicity of the water-locking sublayer increases layer by layer, and the surface energy of the water-locking sublayer increases layer by layer.

3. The packaging structure according to claim 1, characterized in that, When n is a positive odd number, the hydrophilicity of the water-locking sublayer from the first layer to the (n+1) / 2th layer increases layer by layer, and the surface energy increases layer by layer; the hydrophilicity of the water-locking sublayer from the (n+1) / 2th layer to the nth layer decreases layer by layer, and the surface energy decreases layer by layer. When n is a positive even number, the hydrophilicity of the water-locking sublayer from the 1st layer to the 2nd layer increases layer by layer, and the surface energy increases layer by layer. The hydrophilicity of the water-locking sublayer from the (n / 2)+1st layer to the nth layer decreases layer by layer, and the surface energy decreases layer by layer.

4. The packaging structure according to claim 1, characterized in that, The thickness of the water-locking layer ranges from 100 nm to 10 μm.

5. The packaging structure according to claim 1, characterized in that, The material of the water-locking layer includes at least one of biomimetic gold, urethane compounds, aldehyde compounds, olefin compounds, aromatic hydrocarbon compounds, polyester compounds, epoxy compounds, silicon oxide, silicon oxynitride, and titanium oxide.

6. The packaging structure according to claim 1, characterized in that, The water-locking layer is prepared by spin coating, slot coating or inkjet printing.

7. The packaging structure according to claim 1, characterized in that, The inorganic layer is made of at least one of silicon nitride, silicon oxide, and silicon oxynitride.

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