Display device and method for manufacturing the same

Abstract

The present invention relates to a display device and a manufacturing method thereof. The display device includes a substrate, a patterned first electrode layer, a dam layer, an electroluminescent layer, a second electrode layer, and a first encapsulation layer. The first encapsulation layer is disposed in the deposition regions formed by the dam layer, and the first encapsulation layers in different said deposition regions are independent of each other, improving the anti-bending ability and lifespan of the display device. The quantum dot photoluminescent layer is coated in the first encapsulation layer, which can prevent the quantum dot photoluminescent layer from being eroded by water and oxygen, resulting in a reduction in luminous efficiency. At the same time, since the first encapsulation layers in different said deposition regions are independently encapsulated, the quantum dot photoluminescent layer can be directly deposited in the deposition regions during the manufacturing process of the corresponding first encapsulation layer, making the overall thickness of the display device relatively thin, reducing the manufacturing process, and lowering the production cost.

Description

Technical Field

[0001] The present invention relates to the field of display technologies, and particularly to a display device and a method for manufacturing the same. Background Art

[0002] Display devices, especially OLED (organic light-emitting devices), are sensitive to water vapor and are prone to failure due to the influence of water vapor. Therefore, the thin film encapsulation layer needs to have strong water and oxygen barrier capabilities (generally required to reach 10 -6 g / cm 2 ·day).

[0003] Research has found that by setting a quantum dot photoluminescent layer and / or a color filter layer in a display screen, the color purity of the light emitted by the display screen can be improved, and the display picture can be made more natural. However, due to the sensitivity of the quantum dot photoluminescent layer to environmental water and oxygen, the luminous efficiency of the quantum dot material after being eroded by water and oxygen often gradually decreases.

[0004] As Figure 1 shown, in a traditional display device 1, after the entire surface of the device body 2 is encapsulated, a quantum dot color filter film 3 is attached to the encapsulation layer 21. The quantum dot color filter film 3 is formed by forming a black matrix layer 32 on a substrate 31, depositing a quantum dot filter layer 33 in the deposition pits formed in the black matrix layer 32, and then attaching it to the encapsulation layer 21 through an adhesive layer 34. However, this method will result in a relatively large overall thickness of the display device 1 and poor bending resistance. Summary of the Invention

[0005] Based on this, it is necessary to provide a display device and a method for manufacturing the same to reduce the overall thickness of the display device.

[0006] A display device includes:

[0007] A substrate;

[0008] A patterned first electrode layer disposed on the substrate;

[0009] A dam layer disposed on the substrate, the dam layer defining a plurality of deposition regions;

[0010] An electroluminescent layer disposed in the deposition regions and connected to the first electrode layer;

[0011] A second electrode layer disposed in the deposition regions and connected to the electroluminescent layer;

[0012] A first encapsulation layer disposed in the deposition regions and connected to the second electrode layer, the first encapsulation layers in different deposition regions being independent of each other; and

[0013] A quantum dot photoluminescent layer, which is encapsulated in the first encapsulation layer and is at least located on the light-emitting path of a part of the electroluminescent layer.

[0014] In one embodiment, the display device further includes a second encapsulation layer, which is disposed between the substrate and the dam layer. The second encapsulation layer defines pixel pits that expose the first electrode layer, and the electroluminescent layer is disposed in the pixel pits.

[0015] In one embodiment, the first encapsulation layer includes a first sub-layer, a second sub-layer, and a third sub-layer. The first sub-layer is disposed on the second electrode layer, the second sub-layer is disposed on the first sub-layer, and the third sub-layer is disposed on the second sub-layer. The first sub-layer and the third sub-layer are inorganic encapsulation layers, and the second sub-layer is a flexible encapsulation layer.

[0016] In one embodiment, the materials of the first sub-layer and the third sub-layer are independently selected from at least one of silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, titanium dioxide, hafnium dioxide, zinc oxide, magnesium oxide, and zirconium oxide; and / or

[0017] The material of the second sub-layer is selected from at least one of silicon carbonitride, silicon oxycarbide, fluorinated silicon oxycarbide, fluorinated silicon carbonitride, polydimethylsiloxane, parylene, polypropylene, polystyrene, and polyimide.

[0018] In one embodiment, the first sub-layer further covers the sidewalls of the dam layer to form deposition pits, and the second sub-layer is disposed in the deposition pits.

[0019] In one embodiment, the third sub-layer and the first sub-layer cooperate to completely wrap the second sub-layer therein.

[0020] In one embodiment, the quantum dot photoluminescent layer is encapsulated in the second sub-layer.

[0021] In one embodiment, the third sub-layer includes a plurality of refractive layers stacked, and the plurality of refractive layers form a distributed Bragg reflector structure to reflect the light emitted by the electroluminescent layer.

[0022] In one embodiment, the refractive layer is an aluminum oxide layer and a zirconium oxide layer.

[0023] In one embodiment, the display device further includes a filter layer, which is disposed on the side of the quantum dot photoluminescent layer away from the substrate, and the filter layer is encapsulated in the second sub-layer.

[0024] In one embodiment, the electroluminescent layer emits blue light, and the quantum dot photoluminescent layer absorbs the blue light emitted by the electroluminescent layer and converts it into green light or red light.

[0025] In one embodiment, the dam layer is made of a light-blocking material; and / or

[0026] In one embodiment, the dam layer is a plurality of strip-shaped partition walls, the plurality of partition walls are arranged in parallel, and a deposition region is formed between adjacent partition walls.

[0027] In one embodiment, the substrate includes a substrate and a TFT driving array disposed on the substrate. The TFT driving array has a source electrode and a drain electrode. The first electrode layer includes a separated first part and a second part. The first part is connected to the electroluminescent layer and the source electrode, and the second part is connected to the second electrode layer and the drain electrode.

[0028] In one embodiment, the second encapsulation layer is an inorganic encapsulation layer.

[0029] In one embodiment, a passivation layer is provided on a side of the dam layer away from the second encapsulation layer.

[0030] In one embodiment, the material of the passivation layer is selected from at least one of octadecyltrichlorosilane, octadecanethiol, octadecylphosphoric acid, docosyltrichlorosilane, octadecyltrimethoxysilane, dodecyl alcohol, octadecene, polymethyl methacrylate, and polyvinylpyrrolidone.

[0031] In one embodiment, the thickness of the second encapsulation layer is 0.5 μm to 2 μm.

[0032] In one embodiment, the thickness of the first sub-layer is 30 nm to 500 nm.

[0033] In one embodiment, the thickness of the second sub-layer is 2 μm to 12 μm.

[0034] In one embodiment, the height of the dam layer is 1 μm to 20 μm.

[0035] In one embodiment, the thickness of the quantum dot photoluminescent layer is 50 nm to 500 nm.

[0036] A method for manufacturing a display device, characterized by comprising the following steps:

[0037] Providing a substrate provided with a patterned first electrode layer;

[0038] A dam layer is fabricated on the substrate, and the dam layer defines a plurality of deposition regions;

[0039] An electroluminescent layer is fabricated in the deposition regions, and the electroluminescent layer is connected to the first electrode layer;

[0040] A second electrode layer is fabricated in the deposition regions, and the second electrode layer is connected to the electroluminescent layer;

[0041] A first encapsulation layer and a quantum dot photoluminescent layer are fabricated in the deposition regions, such that the quantum dot photoluminescent layer is encapsulated in the first encapsulation layer and is at least located on the light-emitting path of a part of the electroluminescent layer, and the first encapsulation layers in different deposition regions are independent of each other.

[0042] In one embodiment, before fabricating the dam layer, the preparation method further includes the following steps:

[0043] A second encapsulation layer is fabricated on the substrate, and the second encapsulation layer defines pixel pits, and the pixel pits expose the first electrode layer;

[0044] The electroluminescent layer is disposed in the pixel pits, and the dam layer is disposed on the second encapsulation layer.

[0045] Compared with the existing solution, the above display device and its preparation method have the following beneficial effects:

[0046] The above display device is provided with a first encapsulation layer and a quantum dot photoluminescent layer, and the first encapsulation layers in different deposition regions are independent of each other, such that when the display device is bent, the second encapsulation layer is not easily affected by external stress, the overall stress of the display screen is reduced, and the bending resistance and lifespan of the display device are improved. The quantum dot photoluminescent layer is encapsulated in the first encapsulation layer and is at least located on the light-emitting path of a part of the electroluminescent layer, and is used to absorb the light emitted by the corresponding electroluminescent layer and convert it into light of other colors and emit it outward, which can make the light-emitting color purity of the display screen better and make the display picture more natural. The quantum dot photoluminescent layer is encapsulated in the first encapsulation layer, which can prevent the quantum dot photoluminescent layer from being eroded by water and oxygen and causing a reduction in luminous efficiency. At the same time, since the first encapsulation layers in different deposition regions are independently encapsulated, the quantum dot photoluminescent layer can be directly deposited in the deposition regions during the fabrication process of the corresponding first encapsulation layer, such that the overall thickness of the display device is relatively thin, the fabrication process is reduced, and the production cost is lowered. Description of the Drawings

[0047] Figure 1 It is a schematic diagram of a conventional display device bonded with a quantum dot color filter;

[0048] Figure 2 It is a schematic structural diagram of a display device according to an embodiment;

[0049] Figure 3 Another schematic diagram of the display device shown; Figure 2 Another schematic diagram of the display device shown;

[0050] Figure 4 Schematic diagram of fabricating the first electrode layer on the substrate;

[0051] Figure 5 Another; Figure 2 Schematic diagram of the second encapsulation layer exposing the first electrode layer in the display device shown;

[0052] Figure 6 Schematic diagram of fabricating the second encapsulation layer on the substrate;

[0053] Figure 7 Schematic diagram of the ink forming a film in the pixel pit;

[0054] Figure 8 Schematic diagram of fabricating the dam layer on the second encapsulation layer;

[0055] Figure 9 Another; Figure 2 Schematic diagram of the distribution of the dam layer in the display device shown;

[0056] Figure 10 Schematic diagram of forming the light-emitting functional layer in the pixel pit;

[0057] Figure 11 Schematic diagram of removing the light-emitting functional material in the connection hole;

[0058] Figure 12 Schematic diagram after the light-emitting functional material in the connection hole is removed;

[0059] Figure 13 Schematic diagram of fabricating the second electrode layer on the light-emitting functional layer;

[0060] Figure 14 Schematic diagram of forming the passivation layer in the groove on the dam layer;

[0061] Figure 15 Schematic diagram of fabricating the first sub-layer on the second electrode layer;

[0062] Figure 16 Schematic diagram of fabricating the first part of the second sub-layer on the second electrode layer;

[0063] Figure 17 Schematic diagram of fabricating the quantum dot photoluminescence layer on the first part of the second sub-layer;

[0064] Figure 18 Schematic diagram of fabricating the filter layer on the quantum dot photoluminescence layer;

[0065] Figure 19 Schematic diagram for manufacturing the second part of the second sub-layer;

[0066] Description of reference numerals:

[0067] 1. Conventional display device; 2. Device body; 21. Encapsulation layer; 3. Quantum dot color filter film; 31. Substrate; 32. Black matrix layer; 33. Quantum dot filter layer; 34. Adhesive layer; 100. Display device; 110. Substrate; 101. Red sub-pixel; 102. Green sub-pixel; 103. Blue sub-pixel; 120. First electrode layer; 121. First part of the first electrode layer; 122. Second part of the first electrode layer; 130. Second encapsulation layer; 131. Pixel pit; 132. Connection hole; 140. Dam layer; 141. Deposition area; 142. Groove; 143. Partition wall; 150. Electroluminescent layer; 151. Light-emitting functional ink; 160. Second electrode layer; 170. First encapsulation layer; 171. First sub-layer; 172. Second sub-layer; 173. Third sub-layer; 1721. First part of the third sub-layer; 1722. Second part of the third sub-layer; 1712. Deposition pit; 180. Quantum dot photoluminescent layer; 190. Filter layer; 200. Passivation layer; 300. Laser etching equipment. Detailed implementation manners

[0068] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0069] It should be noted that when an element is referred to as being "disposed on" another element, it can be directly on the other element or there can also be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be a middle element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only implementation manner.

[0070] In the description of the present invention, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features.

[0071] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this invention belongs. The terms used in the specification of this invention are for the purpose of describing specific embodiments only and are not intended to limit the invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0072] Please refer to Figure 2 As shown, a display device 100 according to an embodiment of the present invention includes a substrate 110, a patterned first electrode layer 120, a dam layer 140, an electroluminescent layer 150, a second electrode layer 160, a first encapsulation layer 170, and a quantum dot photoluminescent layer 180.

[0073] The patterned first electrode layer 120 is disposed on the substrate 110. The dam layer 140 is disposed on the substrate 110, defining a plurality of deposition regions 141. The electroluminescent layer 150 is disposed in the deposition regions 141 and connected to the first electrode layer 120. The second electrode layer 160 is disposed in the deposition regions 141 and connected to the electroluminescent layer 150. The first encapsulation layer 170 is disposed in the deposition regions 141 and connected to the second electrode layer 160. The first encapsulation layers 170 of different deposition regions 141 are independent of each other, that is, there is no direct connection between the first encapsulation layers 170 in different deposition regions 141. The quantum dot photoluminescent layer 180 is encapsulated in the first encapsulation layer 170 and at least located on the light-emitting path of at least a part of the electroluminescent layer 150.

[0074] The above display device 100 is provided with a first encapsulation layer 170 and a quantum dot photoluminescent layer 180. The first encapsulation layers 170 of different deposition regions 141 are independent of each other, so that the second encapsulation layer 170 of the display device 100 is not easily affected by external stress when bent, reducing the overall stress of the display screen and improving the bending resistance and lifespan of the display device 100. The quantum dot photoluminescent layer 180 is encapsulated in the first encapsulation layer 170 and at least located on the light-emitting path of at least a part of the electroluminescent layer 150, and is used to absorb the light emitted by the corresponding electroluminescent layer 150 and convert it into light of other colors and emit it outward, which can make the light-emitting color purity of the display screen better and the display picture more natural. The quantum dot photoluminescent layer 180 is encapsulated in the first encapsulation layer 170, which can prevent the quantum dot photoluminescent layer 180 from being eroded by water and oxygen and resulting in a reduction in luminous efficiency. At the same time, since the first encapsulation layers 170 of different deposition regions 141 are independently encapsulated, the quantum dot photoluminescent layer 180 can be directly deposited in the deposition regions 141 during the manufacturing process of the corresponding first encapsulation layer 170, making the overall thickness of the display device 100 relatively thin, reducing the manufacturing process, and lowering the production cost.

[0075] For example, please refer to Figure 3As shown, the display device 100 includes a red sub-pixel 101, a green sub-pixel 102, and a blue sub-pixel 103.

[0076] The light emitted by the electroluminescent layer 150 in each sub-pixel is blue light (wavelength range: 450 - 435 nm). A green quantum dot photoluminescent layer 180 is provided on the light-emitting path of the electroluminescent layer 150 of the green sub-pixel 102 to absorb blue light and emit green light (wavelength range: 577 - 492 nm). A red quantum dot photoluminescent layer 180 is provided on the light-emitting path of the electroluminescent layer 150 of the red sub-pixel 101 to absorb blue light and emit red light (wavelength range: 760 - 622 nm). No quantum dot photoluminescent layer 180 is provided on the light-emitting path of the electroluminescent layer 150 of the blue sub-pixel 103, and the blue light is maintained. The quantum dot photoluminescent layer 180 is encapsulated in the first encapsulation layer 170 of the red sub-pixel 101 and the green sub-pixel 102, which can prevent the quantum dot photoluminescent layer 180 from being eroded by water and oxygen, resulting in a reduction in luminous efficiency.

[0077] In one example, the substrate 110 includes a substrate, a TFT driving array provided on the substrate, and a planarization layer provided on the intermediate insulating layer.

[0078] The substrate can be a rigid substrate or a flexible substrate. The rigid substrate can be made of ceramic materials, various glass materials, etc. The flexible substrate can be PI (polyimide) and its derivatives, PEN (polyethylene naphthalate), PEP (phosphoenolpyruvate), and diphenylene ether resin, etc.

[0079] The TFT driving array is a thin-film circuit required in a high-precision display screen. The TFT driving array can specifically be a TFT active driving array, which includes an active layer, a gate insulating layer, a gate layer, an intermediate insulating layer, a source electrode, a drain electrode, and TFT devices, capacitor devices, conductive lines, and resistor devices formed by their combination. The function of the TFT driving array is to actively drive the electroluminescent layer 150 to emit light. Compared with the passive driving method, the TFT active driving array has a more precise single-pixel current and voltage control ability, thus achieving high-precision display.

[0080] The planarization layer mainly plays a planarization role. At the same time, its material properties enable it to spread better on the uneven surface to form a relatively flat film surface, so that the materials on it can form a film on a relatively flat surface, ensuring the stability of the materials on it and reducing the risk of short circuits and open circuits. The material of the planarization layer can be an organic photoresist material such as polyimide (PI), and can be a patterned film layer formed by coating, exposure, and development.

[0081] Such as Figure 4As shown, the first electrode layer 120 is formed by depositing a conductive layer on the substrate 110. The first electrode layer 120 is electrically connected to the TFT driving array and, as part of the light-emitting device structure, serves to inject holes or electrons.

[0082] As Figure 4 and Figure 5 shown, the first electrode layer 120 includes a first portion 121 connected to the electroluminescent layer 150 and a second portion 122 connected to the second electrode layer 160. The first portion 121 and the second portion 122 are separated from each other and insulated from each other, and are respectively connected to the source and drain of the TFT driving array.

[0083] Optionally, the material of the first electrode layer 120 can be a metal oxide conductive material such as ITO (indium tin oxide), IZO (indium zinc oxide), an organic conductive material such as PEDOT (3,4-ethylenedioxythiophene monomer), a conductive metal such as aluminum, molybdenum, titanium, copper, silver, gold and their alloys, a composite laminate, etc.

[0084] In a specific example, the first electrode layer 120 is an ITO / Ag / ITO laminate. The Ag coating serves as a reflective layer to concentrate the light emitted radially from the electroluminescent layer 150 and emit it towards the top. The ITO serves to match the work function of the hole injection and transport layer in the display device 100, enabling better injection of electrons / holes into the light-emitting layer and facilitating an improvement in the efficiency of the display device 100.

[0085] As Figure 2 shown, in one example, the display device 100 further includes a second encapsulation layer 130 disposed between the substrate 110 and the dam layer 140. The second encapsulation layer 130 defines pixel pits 131 that expose the first electrode layer 120, and the electroluminescent layer 150 is disposed in the pixel pits 131.

[0086] In the display device 100 of the above example, a second encapsulation layer 130 is provided on the substrate 110. The second encapsulation layer 130 is disposed between the substrate 110 and the dam layer 140, and the electroluminescent layer 150 is disposed in the pixel pits 131. Thus, the first encapsulation layer can better protect the electroluminescent layer 150 from moisture intrusion.

[0087] As Figure 6As shown, the second encapsulation layer 130 is formed by depositing encapsulation material on the substrate 110. The second encapsulation layer 130 covers the edge of the first electrode layer 120, and the second encapsulation layer 130 has pixel pits 131 that expose the first electrode layer 120. More specifically, the pixel pits 131 expose the first part 121 of the first electrode layer, and the pixel holes supply the deposition of the electroluminescent layer 150. The second encapsulation layer 130 also has connection holes 132 that expose the second part 122 of the first electrode layer, and the connection holes 132 are for the subsequent connection of the second electrode layer 160 to the first electrode layer 120.

[0088] In the traditional device structure, the second electrode layer (generally the cathode) is a planar coating in the display area, and its connection to the driving circuit is set outside the display area and is connected to the driving circuit through a large-area cathode overlapping area (including vias and exposed electrode structures), and finally forms a loop to light up the device. However, in the present invention, the device is encapsulated by a separated encapsulation mode. In this case, if the second electrode layer is deposited in a planar manner, it cannot be perfectly encapsulated. Therefore, in the present invention, the second electrode layer 160 is disposed in each deposition area 141 instead of being deposited in a planar manner, and is connected to the second part 122 of the second electrode layer 160 through the connection holes 132 on the second encapsulation layer 130, and is finally connected to the ground / low-level line in the driving circuit, and a current path can also be achieved.

[0089] In one example, the second encapsulation layer 130 covers the edge of the first electrode layer 120, which can avoid the short-circuit risk between the electroluminescent layer 150 and the electrode layer, and better avoid the invasion of water vapor into the first electrode layer 120.

[0090] In one example, the second encapsulation layer 130 is an inorganic encapsulation layer, which has a relatively hard film quality and a large film stress when bent. Generally, it can be made of inorganic materials and has a strong water and oxygen barrier ability, effectively preventing water vapor from invading the first electrode layer 120 from the dam layer 140.

[0091] The material of the second encapsulation layer 130 should avoid using materials with too strong hydrophobicity. The second encapsulation layer 130 with too strong hydrophobicity may hinder the flow of ink in the pixel pits 131, resulting in the ink being unable to flow evenly and thus unable to be evenly filled into the concave pits formed by the second encapsulation layer 130, resulting in the defect of uneven light emission.

[0092] Optionally, the material of the second encapsulation layer 130 can be selected from but not limited to at least one of silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, titanium dioxide, hafnium dioxide, zinc oxide, magnesium oxide, and zirconium oxide.

[0093] In a specific example, the material of the second encapsulation layer 130 is silicon oxynitride, which mainly plays a role in isolating water and oxygen, and its hydrophilicity can be finely adjusted by controlling its oxygen content.

[0094] The preparation method of the second encapsulation layer 130 may be, but is not limited to, plasma chemical vapor deposition, atomic layer deposition, ion beam deposition, magnetron sputtering deposition, etc. In a specific example, the second encapsulation layer 130 is prepared by plasma chemical vapor deposition.

[0095] Since the electroluminescent layer 150 has not been fabricated when the second encapsulation layer 130 is prepared, the preparation process temperature of the second encapsulation layer 130 can be relatively high, and the temperature range for depositing the thin film can be 50°C to 400°C.

[0096] The hydrophilic and hydrophobic properties of the second encapsulation layer 130 affect the spreading property of the subsequent inkjet ink droplets. Specifically, as Figure 7 shown, if the hydrophobicity of the second encapsulation layer 130 is too high, the light-emitting functional ink 151 in the dam cannot flow evenly, thereby reducing the uniformity of the electroluminescent layer 150, and even causing the materials of the electroluminescent layer 150 in some pixels, affecting the device performance.

[0097] The thickness of the second encapsulation layer 130 is larger than that of the electroluminescent layer 150. In one example, the thickness of the second encapsulation layer 130 is 0.5 μm to 2 μm.

[0098] As Figure 8 shown, the dam layer 140 is formed by depositing dam materials on the second encapsulation layer 130. In one example, the material of the dam layer is selected from at least one of polyimide, phenolic resin, polymethyl methacrylate, and PBS. Using the above materials, the fabrication of the dam layer can be completed quickly.

[0099] One of the functions of the dam layer 140 is to separate the printing materials, so that OLED materials with different light-emitting colors can be printed between different dams, and finally achieve full-color display. The dam layer 140 should have a certain hydrophobic ability, so that the subsequent ink droplets dropped into the deposition area 141 are restricted within the deposition area 141 and will not flow between different deposition areas 141 to form defects such as bridging, which will ultimately lead to poor color mixing of the OLED display.

[0100] As Figure 9 shown, in one example, the dam layer 140 is a plurality of strip-shaped partition walls 143, and the plurality of partition walls 143 are arranged in parallel, and the deposition area 141 is formed between adjacent partition walls 143. This setting method can change the inkjet method from single printing to linear printing, which can reduce the accuracy of the inkjet device in the linear printing direction, reduce the equipment investment cost while meeting the accuracy requirements.

[0101] As Figure 2As shown, in one example, a passivation layer 200 is provided on the side of the dam layer 140 away from the second encapsulation layer 130.

[0102] During the fabrication process of the display device 100, the passivation layer 200 on the dam layer 140 can separate the first encapsulation layer 170 and the fourth encapsulation layer in adjacent pixels, forming an independent pixel encapsulation structure, so that the second encapsulation layer 130 is not easily affected by external stress when the display device 100 is bent, reducing the overall stress of the display screen and improving the bending resistance and lifespan of the display device 100.

[0103] The material of the passivation layer 200 can be but is not limited to ODTS (octadecyltrichlorosilane), ODT (octadecanethiol), ODPA (octadecylphosphonic acid), DTS (docosyltrichlorosilane), ODS (octadecyltrimethoxysilane), dodecanol, octadecene, PMMA (polymethyl methacrylate), PVP (polyvinylpyrrolidone), etc.

[0104] In one example, the material of the passivation layer 200 is ODTS, whose main chain is formed by connecting alkane carbon chains, and its tail functional group is an alkyl group (-CH 3 ), which has strong hydrophobicity. During the step of introducing the organic source for atomic layer deposition, the organic source for atomic layer deposition will not adsorb on this film layer, which can effectively prevent the growth of the atomic layer deposition (ALD) thin film, and thus play the role of self-assembled patterning of atomic layer deposition.

[0105] As Figure 10 shown, the electroluminescent layer 150 is formed by depositing a light-emitting functional material in the pixel pit 131. It should be noted that if the light-emitting functional material is deposited into the connection hole 132, the light-emitting functional material in the connection hole 132 needs to be removed, for example, etched by a laser etching device 300 to restore the connection hole 132, as Figure 11 and Figure 12 shown.

[0106] The electroluminescent layer 150 includes a light-emitting material layer, where the light-emitting material can be an organic light-emitting material, a quantum dot light-emitting material, etc. In addition, the electroluminescent layer 150 can further include a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, etc.

[0107] As Figure 13 shown, the second electrode layer 160 is formed by depositing a conductive layer on the electroluminescent layer 150. At the same time, the second electrode layer 160 is connected to the second part 122 of the first electrode layer through the connection hole 132.

[0108] The function of the second electrode layer 160 is equivalent to that of the first electrode layer 120, serving as an electrical connection. One of the first electrode layer 120 and the second electrode layer 160 serves as the anode, and the other serves as the cathode, jointly forming a display component with the electroluminescent layer 150. After being connected to the circuit, current flows through the anode, the electroluminescent layer 150, and the cathode to form a loop.

[0109] The material of the second electrode layer 160 can be a metal oxide conductive material such as ITO (indium tin oxide), IZO (indium zinc oxide), etc., can be an organic conductive material such as PEDOT (3,4-ethylenedioxythiophene monomer), etc., or can be a conductive metal such as aluminum, molybdenum, titanium, copper, silver, gold, etc. and their alloys, composite laminates, etc. If the display device 100 is a top-emitting device, it is required that the material of the second electrode layer 160 has high transparency, high conductivity, and relatively stable physical and chemical properties within its film thickness range.

[0110] Such as Figure 14 As shown, in one example, before depositing the first encapsulation layer 170, a passivation layer 200 is deposited and formed in the groove 142 on the side of the dam layer 140 away from the second encapsulation layer 130.

[0111] Such as Figure 2 As shown, in one example, the first encapsulation layer 170 includes a first sub-layer 171, a second sub-layer 172, and a third sub-layer 173. The first sub-layer 171 is disposed on the second electrode layer 160, the second sub-layer 172 is disposed on the first sub-layer 171, and the third sub-layer 173 is disposed on the second sub-layer 172. The first sub-layer 171 and the third sub-layer 173 are inorganic encapsulation layers, and the second sub-layer 172 is a flexible encapsulation layer.

[0112] Such as Figure 15 As shown, after depositing and forming the passivation layer 200, the first sub-layer 171 is deposited on the second electrode layer 160. Due to the presence of the passivation layer 200, the first sub-layers 171 in different deposition regions 141 are independent of each other.

[0113] In one example, the first sub-layer 171 is an inorganic encapsulation layer with a relatively hard film quality and a relatively large film stress during bending, and is generally made of an inorganic material. The first sub-layer 171 needs to have strong water and oxygen barrier capabilities and a high visible light transmittance.

[0114] Optionally, the material of the first sub-layer 171 can be selected from but not limited to at least one of silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, titanium dioxide, hafnium dioxide, zinc oxide, magnesium oxide, and zirconium oxide.

[0115] In a specific example, the first sub-layer 171 is a nano-laminate of aluminum oxide / zirconium oxide, mainly serving to isolate water and oxygen.

[0116] The first sublayer 171 may be prepared by, but is not limited to, plasma chemical vapor deposition, atomic layer deposition, ion beam deposition, magnetron sputtering deposition, etc. In a specific example, the first sublayer 171 is prepared by atomic layer deposition.

[0117] Since the first sublayer 171 needs to have a high visible light transmittance, it is preferably thinner under the premise of having a certain water and oxygen blocking ability. In one example, the thickness of the first sublayer 171 is 30nm to 500nm.

[0118] like Figure 2 As shown, in one example, there is no direct contact between the second electrode layer 160 and the dam layer 140 , and the two are separated by the first sublayer 171 , thereby preventing water vapor from invading the second electrode layer 160 through the dam layer 140 .

[0119] like Figure 15 As shown, in one example, the first sublayer 171 also covers the sidewall of the deposition area 141 to form a deposition pit 1712, and the second sublayer 172 is disposed in the deposition pit 1712. In this way, water vapor is prevented from invading through the sidewall of the dam layer 140, and the water and oxygen barrier performance can be improved.

[0120] The second sublayer 172 is a flexible packaging layer, has good deformability, and can buffer the stress of the upper and lower film layers. Optionally, the material of the second sublayer 172 can be selected from but not limited to at least one of silicon carbonitride, silicon carbide, fluorinated silicon carbon oxide, fluorinated silicon carbon nitride, polydimethylsiloxane, polyparaxylene, polypropylene, polystyrene and polyimide.

[0121] The second sublayer 172 may be prepared by inkjet printing, nano transfer printing, etc. In a specific example, the second sublayer 172 is prepared by inkjet printing. Ink is dropped into the deposition pit 1712 formed in the first sublayer 171 by inkjet printing, and its thickness is controlled to be equivalent to the height of the dam layer 140, so that the surface of the display screen is basically flat after the second sublayer 172 is completed. The thickness of the second sublayer 172 should be set in accordance with the height of the dam layer 140, so that the upper surface of the second sublayer 172 is basically flat with the upper surface of the dam layer 140, or slightly higher than the upper surface of the dam layer 140.

[0122] Compared with the buffer layer in traditional device packaging (whole-surface coating with a thickness of 8 to 12 μm), the second sublayer 172 is discrete and can be thinner, about 1 to 6 μm, so that the display device 100 has reliable anti-bending performance.

[0123] like Figures 16 to 19As shown, the preparation of the second sub-layer 172 can be carried out in two steps. That is, first form the first part 1721 of the second sub-layer on the first sub-layer 171. After forming the quantum dot photoluminescent layer 180 on the first part 1721 of the second sub-layer, form the second part 1722 of the second sub-layer on the quantum dot photoluminescent layer 180.

[0124] The height of the second sub-layer 172 wrapped with the quantum dot photoluminescent layer 180 is not higher than the height of the dam layer 140. For example, it can be set to 1 / 3 of the height of the dam layer 140. In order to achieve a certain planarization and foreign object coverage effect, its thickness is generally set to 2 - 12 μm. And the height of the second sub-layer 172 not wrapped with the quantum dot photoluminescent layer 180 can be the same as that of the second sub-layer 172 wrapped with the quantum dot photoluminescent layer 180, or it can be directly printed to a thickness equivalent to the height of the dam layer 140. A preferred solution is that the second sub-layer 172 not wrapped with the quantum dot photoluminescent layer 180 is also coated twice, which can improve its planarization ability.

[0125] The third sub-layer 173 is disposed on the second sub-layer 172. The third sub-layer 173 is an inorganic encapsulation layer, which is generally made of inorganic materials. The third sub-layer 173 needs to have strong water and oxygen barrier capabilities and high visible light transmittance.

[0126] Optionally, the material of the third sub-layer 173 can be selected from but not limited to at least one of silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, titanium dioxide, hafnium dioxide, zinc oxide, magnesium oxide, and zirconium oxide.

[0127] In the specific example shown, the third sub-layer 173 cooperates with the first sub-layer 171 to completely wrap the second sub-layer 172 therein. In this way, by completely wrapping the second sub-layer 172 with relatively low water and oxygen barrier performance, the water and oxygen barrier performance can be improved.

[0128] As the first sub-layer 171 of the inorganic encapsulation layer generally has relatively large internal stress and it is not easy to completely cover the foreign objects on the encapsulation surface. There are easily phenomena of thin film thickness deviation and fracture at the tip of the foreign object and the bottom of the step with a negative slope angle. Especially when applied in a flexible display, the encapsulation film is likely to break and peel off or crack at the place with foreign objects, resulting in encapsulation failure. In the above example, by setting the soft second sub-layer 172, the stress between the upper and lower film layers can be buffered, enabling the display device 100 to have better reliability and anti-bending properties. At the same time, the second sub-layer 172 can also cover the dust and impurities that may fall during the encapsulation process, making the edges and corners of the impurities more rounded, not easily forming a channel for water and oxygen permeation, and having a certain water and oxygen barrier performance.

[0129] Generally, the height of the dam layer 140 is set as low as possible because the higher the height, the easier it is for the film thickness of the encapsulation film layer to be too low at the side walls and corners of the dam layer 140, and peeling may occur severely, ultimately resulting in the invasion of water and oxygen and the failure of encapsulation. In addition, an overly high dam is not conducive to the planarization of the surface topography of the device by the second sub-layer 172, and the second sub-layer 172 is prone to mura phenomenon, which will ultimately affect the encapsulation and display effects. One advantage of the present invention is that the height of the dam layer 140 can be set higher, thereby preventing the occurrence of bridging during printing, and the above-mentioned disadvantages of the overly high dam layer 140 are solved by the separated encapsulation method. Specifically, after the deposition of the second sub-layer 172 is completed, the second sub-layer 172 will basically fill the pits of the dam layer 140, while buffering stress and covering foreign object defects, it also plays a role in planarization, enabling the third sub-layer 173 to be deposited on a relatively flat plane, improving the encapsulation reliability. In one example, the height of the dam layer 140 is set to 1 - 20 μm.

[0130] In one example, the third sub-layer 173 in the first encapsulation layer 170 wrapping the quantum dot light-emitting layer 180 includes a plurality of refractive layers stacked, and the plurality of refractive layers form a distributed Bragg reflector structure to reflect the light emitted by the electroluminescent layer 150.

[0131] By setting a plurality of refractive layers with different refractive indices, a distributed Bragg reflector structure is formed, which plays a role in reflecting incident light within a specific wavelength range, absorbs the remaining light emitted by the electroluminescent layer 150, and only allows the corresponding color light to pass through, further improving color purity. Specifically, assuming that the wavelength of the light emitted by the electroluminescent layer 150 is λ, the refractive index of one refractive layer in the third sub-layer 173 is n1, the thickness is d1, the refractive index of another refractive layer is n2, and the thickness is d2, to achieve the reflection of light with a wavelength of λ, the above parameters should satisfy: n1·d1 = n2·d2 = 1 / 4·λ.

[0132] For example, when the electroluminescent layer 150 emits blue light, the refractive layer can adopt an alumina layer (refractive index range: 1.6 - 1.7) and a zirconia layer (refractive index range: 2.1 - 2.2), that is, the third sub-layer 173 in the first encapsulation layer 170 wrapping the quantum dot light-emitting layer 180 is composed of an alumina layer and a zirconia layer stacked. The stack of the alumina layer and the zirconia layer can not only form a good water and oxygen barrier effect, but also play a role in reflecting part of the blue light through the stack setting of the film thickness.

[0133] As Figure 2 shown, in one example, the quantum dot light-emitting layer 180 is coated in the second sub-layer 172. Due to the use of quantum dot materials, the full width at half maximum of the emitted light wavelength is relatively narrow and the color purity is high, which can well improve the color gamut of OLED display.

[0134] The host material of the quantum dot photoluminescent layer 180 can be cadmium selenide, indium phosphide, or perovskite material. By controlling the particle size of the quantum dots, light of different wavelengths can be emitted.

[0135] A preparation method of the quantum dot photoluminescent layer 180 is as follows:

[0136] First, the ink formed by the quantum dots and the corresponding mixed solvent is printed into the deposition area 141 formed by the dam layer 140, then vacuum drying is carried out, and finally thermal curing is carried out, and the curing temperature is generally 150 - 300 °C.

[0137] Another preparation method of the quantum dot photoluminescent layer 180 is as follows:

[0138] First, the ink formed by the quantum dots and the corresponding polymer photosensitive organic glue solvent is printed into the deposition area 141 formed by the dam layer 140, and then UV curing is carried out. This method does not require high-temperature curing and can avoid the peeling phenomenon caused by the stress mismatch between the quantum dot light conversion layer and the encapsulation film layer due to high-temperature curing.

[0139] The quantum dot photoluminescent layer 180 can be arranged on the light-emitting path of all the electroluminescent layers 150, and the light emitted by the electroluminescent layers 150 can be converted into light of colors such as red, blue, and green according to the display needs. The quantum dot photoluminescent layer 180 can also be arranged only in part of the deposition areas 141 and only on the light-emitting paths of part of the electroluminescent layers 150. For example, Figure 3 As shown, the display device 100 includes a red sub-pixel 101, a green sub-pixel 102, and a blue sub-pixel 103. The light emitted by the electroluminescent layers 150 in each sub-pixel is blue light. A green quantum dot photoluminescent layer 180 is arranged on the light-emitting path of the electroluminescent layer 150 of the green sub-pixel 102 to absorb the blue light and emit green light. A red quantum dot photoluminescent layer 180 is arranged on the light-emitting path of the electroluminescent layer 150 of the red sub-pixel 101 to absorb the blue light and emit red light. The quantum dot photoluminescent layer 180 is not arranged on the light-emitting path of the electroluminescent layer 150 of the blue sub-pixel 103, and the blue light is maintained.

[0140] In one example, the thickness of the quantum dot photoluminescent layer 180 is 50 - 500 nm.

[0141] As Figure 2As shown, in one example, the display device 100 further includes a filter layer 190. The filter layer 190 is disposed on a side of the quantum dot light-emitting layer 180 away from the substrate 110, and the filter layer 190 is encapsulated in the first encapsulation layer 170. The filter layer 190 can allow light of the color emitted by the quantum dot light-emitting layer 180 to pass through, and absorb light of other colors except the color emitted by the quantum dot light-emitting layer 180. For example, the corresponding electroluminescent layer 150 emits blue light, the quantum dot light-emitting layer 180 is converted into red light, and the filter layer 190 can absorb blue light.

[0142] The filter layer 190 contains dyes of corresponding colors, and only allows light of corresponding color wavelengths to pass through, and absorbs other visible light. By providing the filter layer 190, in the case where the light emitted by the electroluminescent layer 150 cannot be completely absorbed by the quantum dot light-emitting layer 180, the remaining light emitted by the electroluminescent layer 150 can be absorbed, and only the light of the corresponding color is allowed to pass through, further improving the color purity.

[0143] In addition, the color filter layer 190 can also prevent light of colors other than the corresponding color in the environment from entering the display screen, reduce the light reflected from the pixel area in the non-display state, and improve the contrast of the display device 100.

[0144] In one example, the dam layer 140 is made of a light-blocking material, for example, made of a black matrix material, and the black matrix material can absorb visible light, making it difficult for external light to penetrate.

[0145] Based on the fact that the black matrix material can be exposed and patterned, it can absorb the ambient light outside the display device 100, preventing the ambient light from irradiating the reflective material (such as metal lines) in the display screen and then being reflected into the eyes of the observer, resulting in a decrease in the display contrast.

[0146] In order to achieve a lower bending and curling radius and achieve a foldable and curlable display form, it is often required that the overall thickness of the display screen be as thin as possible. Currently, the thickness of the light-emitting functional film layer and the driving device of the OLED display screen is very thin, generally less than 10 μm. However, other functional layers of the display screen are very thick, making the overall film thickness of the display screen greater than 100 μm. For example, a circular polarizer is provided in the display screen, and the circular polarizer is an important functional group layer for improving the display contrast. The circular polarizer uses the principle of polarization to prevent the ambient light from entering the display screen and then being reflected by some reflective film layers such as metal lines in the display screen and entering the human eye. Generally, the thickness of the circular polarizer on the market is often greater than 100 μm, which is an important factor restricting the further reduction of the bending radius of the flexible display. The display device 100 in the above example can achieve the effect of replacing the circular polarizer through the cooperation of the black matrix material of the dam layer 140 and the filter layer 190, reducing the overall thickness of the display device 100.

[0147] It can be understood that the light filtering layer 190 can also be omitted.

[0148] Furthermore, the present invention also provides a method for manufacturing the display device 100 according to any one of the above examples, including the following steps:

[0149] Providing a substrate 110 provided with a patterned first electrode layer 120;

[0150] Fabricating a dam layer 140 on the substrate 110, and the dam layer 140 defines a plurality of deposition regions 141;

[0151] Fabricating an electroluminescent layer 150 in the deposition regions 141, and the electroluminescent layer 150 is connected to the first electrode layer 120;

[0152] Fabricating a second electrode layer 160 in the deposition regions 141, and the second electrode layer 160 is connected to the electroluminescent layer 150;

[0153] Fabricating a first encapsulation layer 170 and a quantum dot photoluminescent layer 180 in the deposition regions 141, such that the quantum dot photoluminescent layer 180 is encapsulated in the first encapsulation layer 170 and at least located on the light output path of a part of the electroluminescent layer 150, and the first encapsulation layers 170 in different deposition regions 141 are independent of each other.

[0154] In one example, before fabricating the dam layer 140, the manufacturing method further includes the following steps:

[0155] Fabricating a second encapsulation layer 130 on the substrate 110, and the second encapsulation layer 130 defines pixel pits 131, and the pixel pits 131 expose the first electrode layer 120;

[0156] The electroluminescent layer 150 is disposed in the pixel pits 131, and the dam layer 140 is disposed on the second encapsulation layer 130.

[0157] The following provides a specific example of the display device 100 and its manufacturing method to further illustrate the present invention. However, the present invention is not limited to the following specific examples. It should be understood that the appended claims define the scope of the present invention. Under the guidance of the inventive concept of the present invention, those skilled in the art should realize that certain changes made to the embodiments of the present invention will be covered by the spirit and scope of the claims of the present invention.

[0158] The manufacturing method of a specific example of the display device 100 includes the following steps:

[0159] Step S1, as Figure 4 shown, providing a substrate 110 and forming a first electrode layer 120 on the substrate 110.

[0160] After depositing the ITO / Ag / ITO metal thin film by magnetron sputtering, it is patterned. The difference from a general electrode layer is that the patterned first electrode layer 120 is divided into two parts, namely the first part that will be in direct contact with the OLED device and the second part that is in contact with the second electrode layer 160. These two parts are separated and insulated from each other in the first electrode layer 120 and are respectively connected to the source and drain electrodes of the TFT driving array.

[0161] Step S2, as Figure 6 shown, a second encapsulation layer 130 is fabricated on the substrate 110 on which the first electrode layer 120 is formed.

[0162] The second encapsulation layer 130 is prepared by methods such as evaporation coating, magnetron sputtering, plasma enhanced chemical vapor deposition (PECVD), atomic layer deposition, or molecular layer deposition. One preferred solution is to deposit a SION thin film using the PECVD method. By controlling the gas flow rate during PECVD deposition, the oxygen content of the SION thin film can be conveniently controlled, thereby finely tuning the hydrophilic property of the second encapsulation layer 130.

[0163] Step S3, as Figure 8 shown, a dam layer 140 is fabricated on the second encapsulation layer 130.

[0164] A black matrix material is coated on the second encapsulation layer 130 using methods such as spin coating or slot coating to form a black photosensitive resin film, and a patterned dam layer 140 is obtained through steps such as exposure, development, and curing. The dam layer 140 has a deposition region 141 that communicates with the pixel pits 131 of the second encapsulation layer 130, exposing the first electrode layer 120. A groove 142 is formed on the top of the dam layer 140 (i.e., on the side away from the substrate 110). The groove 142 can be obtained using a "half mask" patterning method. Different from a general exposure mask, the mask used in this case has a light passing rate of 20% at the groove 142 during exposure, a light passing rate of 100% inside the dam, and 0% for the rest. Since the amount of light irradiated at the groove 142 is small, only a small amount of the material at the top of the dam layer 140 reacts with the light and is removed after development, finally forming a pattern as Figure 8 shown. As Figure 9 shown, in this example, the dam layer 140 is a linear structure that runs through the entire display area.

[0165] Step S4, as Figure 10 shown, ink containing a blue light OLED material is sprayed into the space between the dam layers 140. For the linear dams, the dropped ink droplets will connect with each other inside the dams to form strips. After curing, most of the material will gather into the pixel pits 131 of the second encapsulation layer 130 to form an electroluminescent layer 150 that can emit blue light.

[0166] Step S5, as Figure 11 and Figure 12 shown, remove the OLED thin film on the second part 122 of the first electrode layer.

[0167] Using the method of laser ablation, irradiate the OLED thin film on the second part 122 of the first electrode layer. After selecting appropriate laser wavelength, energy and frequency, the OLED thin film will be vaporized after irradiation, so that the second part 122 of the first electrode layer is exposed.

[0168] Step 6, as Figure 13 shown, form the second electrode layer 160 between the dam layers 140.

[0169] Using a patterned deposition coating method such as inkjet printing or selective area atomic layer deposition, form the second electrode layer 160 between the dam layers 140. The second electrode layer 160 is connected to the electroluminescent layer 150 and the ground / negative potential line in the TFT driving array. During the lighting process of the OLED, generally, current flows from the high-level line in the TFT line into the first part 121 of the first electrode layer to supply power to the electroluminescent layer 150, and the current flows out through the second electrode layer 160 to the second part 122 of the first electrode layer, and finally forms a loop by connecting to the low-level line in the TFT driving array.

[0170] Step S7, as Figure 14 shown, form the passivation layer 200 in the groove 142 at the top of the dam layer 140.

[0171] Using inkjet printing or microcontact printing technology, deposit a surface modification thin film with a thickness of 1 - 10 nm in the groove 142 at the top of the dam layer 140 between two pixels. The material of the passivation layer 200 is ODTS, its main chain is connected by alkane carbon chains, and its tail functional group is alkyl (-CH3), which has strong hydrophobicity. During the process of introducing the organic source of atomic layer deposition, the organic source of atomic layer deposition will not adsorb on this film layer, which can effectively prevent the growth of the atomic layer deposition (ALD) thin film, and thus play the role of self-assembled patterning of atomic layer deposition.

[0172] Step S8, as Figure 15 shown, form the patterned first sublayer 171 on the second electrode layer 160.

[0173] A second encapsulation film layer is fabricated on the substrate 110 by means of coating such as magnetron sputtering, evaporation, chemical vapor deposition, atomic layer deposition or molecular layer deposition. A preferred solution is to use atomic layer deposition to prepare a nano-laminated film of AlOx / ZrOx. The nano-lamination consists of alternating laminations of AlOx and ZrOx. The thickness of a single-layer film can be 0.5 - 50 nm, and the total thickness range of the lamination can be 30 - 500 nm. The number of laminated layers can be 2 - 5000 layers. Due to the presence of the passivation layer 200 on the dam layer 140, the first sub-layers 171 of adjacent pixels are separated from each other.

[0174] Step S9, as Figure 16 shown, form the first part 1721 of the second sub-layer on the first sub-layer 171.

[0175] Using an inkjet printing process, print the first part 1721 of the second sub-layer on the first sub-layer 171 and only between the dams of the dam layer 140. First, use a large number of precisely dropped inks to form a liquid film with good fluidity on the surface, and then use ultraviolet curing or thermal curing to cure the liquid film.

[0176] Step S10, as Figure 17 shown, form the quantum dot photoluminescent layer 180 on the first part 1721 of the second sub-layer.

[0177] Use fine patterning coating processes such as inkjet printing and nanoimprinting to form the quantum dot photoluminescent layer 180 on the first part 1721 of the second sub-layer. Specifically, form a green quantum dot photoluminescent layer 180 on the light-emitting path of part of the electroluminescent layer 150 to absorb blue light and emit green light, form a red quantum dot photoluminescent layer 180 on the light-emitting path of part of the electroluminescent layer 150 to absorb blue light and emit red light, and do not set the quantum dot photoluminescent layer 180 on the light-emitting path of part of the electroluminescent layer 150 to maintain blue light.

[0178] Step S11, as Figure 18 shown, form the filter layer 190 on the quantum dot photoluminescent layer 180.

[0179] Use fine patterning coating processes such as inkjet printing and nanoimprinting to form the filter layer 190 on the quantum dot photoluminescent layer 180. Among them, form a green filter layer 190 on the green quantum dot photoluminescent layer 180. The green filter layer 190 only allows green light to pass through and absorbs other colors of light. Form a red filter layer 190 on the red quantum dot photoluminescent layer 180. The red filter layer 190 only allows red light to pass through and absorbs other colors of light.

[0180] Step S12, as Figure 19 shown, form the second part 1722 of the second sub-layer on the filter layer 190.

[0181] Using an inkjet printing process, a second part 1722 of the second sub-layer is formed on the light filtering layer 190, such that the first part 1721 and the second part of the second sub-layer cooperate to wrap the quantum dot photoluminescent layer 180 and the light filtering layer 190 therein. And on the first part 1721 of the second sub-layer where the quantum dot photoluminescent layer 180 and the light filtering layer 190 are not formed, the second part 1722 of the second sub-layer is directly formed.

[0182] Step S13, forming a third sub-layer 173 on the second sub-layer 172 to obtain a display device 100 as Figure 2 shown.

[0183] Using coating means such as magnetron sputtering, evaporation, chemical vapor deposition, atomic layer deposition, molecular layer deposition, etc., the coating of the third sub-layer 173 is completed on the second sub-layer 172. Due to the presence of the passivation layer 200 on the dam layer 140, the third sub-layers 173 of adjacent pixels are separated from each other.

[0184] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0185] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. A display device, characterized in that, comprising: a substrate; a patterned first electrode layer disposed on the substrate; a dam layer disposed on the substrate, the dam layer defining a plurality of deposition regions; an electroluminescent layer disposed in the deposition regions and connected to the first electrode layer; a second electrode layer disposed in the deposition regions and connected to the electroluminescent layer; a first encapsulation layer disposed in the deposition regions and connected to the second electrode layer, the first encapsulation layers of different deposition regions being independent of each other; a quantum dot photoluminescent layer, the quantum dot photoluminescent layer being encapsulated in the first encapsulation layer and at least located on the light-emitting path of part of the electroluminescent layer; and a second encapsulation layer, the second encapsulation layer being disposed between the substrate and the dam layer, the second encapsulation layer defining a pixel pit, the pixel pit exposing the first electrode layer, and the electroluminescent layer being disposed in the pixel pit; a passivation layer is provided on a side of the dam layer away from the second encapsulation layer, and the material of the passivation layer is selected from at least one of octadecyltrichlorosilane, octadecanethiol, octadecylphosphoric acid, docosyltrichlorosilane, octadecyltrimethoxysilane, dodecyl alcohol, octadecene, polymethyl methacrylate, and polyvinylpyrrolidone.

2. The display device according to claim 1, characterized in that, the display device further includes the second encapsulation layer covering an edge of the first electrode layer.

3. The display device according to claim 1, characterized in that, the first encapsulation layer includes a first sub-layer, a second sub-layer, and a third sub-layer, the first sub-layer is disposed on the second electrode layer, the second sub-layer is disposed on the first sub-layer, the third sub-layer is disposed on the second sub-layer, the first sub-layer and the third sub-layer are inorganic encapsulation layers, and the second sub-layer is a flexible encapsulation layer.

4. The display device according to claim 3, characterized in that, the materials of the first sub-layer and the third sub-layer are independently selected from at least one of silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, titanium dioxide, hafnium dioxide, zinc oxide, magnesium oxide, and zirconium oxide; and / or the material of the second sub-layer is selected from at least one of silicon carbonitride, silicon oxycarbide, fluorinated silicon oxycarbide, fluorinated silicon carbonitride, polydimethylsiloxane, parylene, polypropylene, polystyrene, and polyimide.

5. The display device according to claim 3, characterized in that, the first sub-layer further covers a sidewall of the dam layer to form a deposition pit, and the second sub-layer is disposed in the deposition pit.

6. The display device according to claim 5, characterized in that, the third sub-layer and the first sub-layer cooperate to completely wrap the second sub-layer therein.

7. The display device according to claim 6, characterized in that, the quantum dot photoluminescent layer is encapsulated in the second sub-layer.

8. The display device according to claim 7, characterized in that, the third sub-layer includes a plurality of refractive layers stacked, and the plurality of refractive layers constitute a distributed Bragg reflector structure to reflect light emitted by the electroluminescent layer.

9. The display device according to claim 8, wherein, the refraction layer is an alumina layer and a zirconia layer.

10. The display device according to claim 7, wherein, the display device further includes a filter layer, the filter layer is disposed on a side of the quantum dot photoluminescent layer away from the substrate, and the filter layer is coated in the second sub-layer.

11. The display device according to claim 10, wherein, the electroluminescent layer emits blue light, and the quantum dot photoluminescent layer absorbs the blue light emitted by the electroluminescent layer and converts it into green light or red light.

12. The display device according to claim 2, wherein, the dam layer is a plurality of strip-shaped partition walls, the plurality of partition walls are arranged in parallel, and a deposition region is formed between adjacent partition walls; and / or the substrate includes a substrate and a TFT driving array disposed on the substrate, the TFT driving array has a source electrode and a drain electrode, the first electrode layer includes a separated first part and a second part, the first part is connected to the electroluminescent layer and the source electrode, and the second part is connected to the second electrode layer and the drain electrode; and / or the second encapsulation layer is an inorganic encapsulation layer.

13. The display device according to claim 12, wherein, the dam layer is made of a light-blocking material.

14. The display device according to claim 3, wherein, the thickness of the first sub-layer is 30 nm to 500 nm; and / or the thickness of the second sub-layer is 2 μm to 12 μm; and / or the height of the dam layer is 1 μm to 20 μm; and / or the thickness of the quantum dot photoluminescent layer is 50 nm to 500 nm.

15. A method for manufacturing a display device, wherein, it includes the following steps: providing a substrate provided with a patterned first electrode layer; fabricating a second encapsulation layer on the substrate, the second encapsulation layer defining pixel pits that expose the first electrode layer; fabricating a dam layer on the second encapsulation layer, the dam layer defining a plurality of deposition regions; fabricating an electroluminescent layer in the deposition regions, the electroluminescent layer being connected to the first electrode layer; fabricating a second electrode layer in the deposition regions, the second electrode layer being connected to the electroluminescent layer; depositing a passivation layer in a groove on a side of the dam layer away from the second encapsulation layer, the material of the passivation layer being selected from at least one of octadecyltrichlorosilane, octadecanethiol, octadecylphosphoric acid, docosyltrichlorosilane, octadecyltrimethoxysilane, dodecyl alcohol, octadecene, polymethyl methacrylate, and polyvinylpyrrolidone; fabricating a first encapsulation layer and a quantum dot photoluminescent layer in the deposition regions, such that the quantum dot photoluminescent layer is coated in the first encapsulation layer and at least located on an out-light path of at least part of the electroluminescent layer, and the first encapsulation layers in different deposition regions are independent of each other.

16. The manufacturing method according to claim 15, wherein, The first encapsulation layer includes a first sub-layer, a second sub-layer, and a third sub-layer. The first sub-layer is disposed on the second electrode layer, the second sub-layer is disposed on the first sub-layer, and the third sub-layer is disposed on the second sub-layer. The first sub-layer and the third sub-layer are inorganic encapsulation layers, and the second sub-layer is a flexible encapsulation layer.

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