Preparation method of quantum dot substrate and quantum dot display panel

Abstract

This invention discloses a method for fabricating a quantum dot substrate and a quantum dot display panel. In one specific embodiment, the method includes: providing a first substrate; forming a first defining portion on the first substrate including a plurality of first baffles extending along a first direction and arranged along a second direction, with gaps formed between adjacent first baffles for accommodating a first quantum dot layer, a second quantum dot layer, and a third quantum dot layer; forming a blocking portion extending along the first direction on the top surface of the first baffles, and forming a first electrode on the top of the blocking portion; forming the first to third quantum dot layers respectively based on a slot coating process, wherein when one of the first to third quantum dot layers is formed based on the slot coating process, an electrical signal is applied to the first electrode to tilt the blocking portion in the second direction, so that the gap for accommodating the quantum dot layer being formed is exposed by the blocking portion and the gap for accommodating the other two quantum dot layers is shielded by the blocking portion; separating the blocking portion to obtain a quantum dot substrate.

Description

Technical Field

[0001] This invention relates to the field of display technology. More specifically, it relates to a method for fabricating a quantum dot substrate and a quantum dot display panel. Background Technology

[0002] Currently, photoluminescent quantum dot (QD) display panels are typically designed to excite red, green, and blue quantum dot layers using short-wavelength, high-energy excitation light such as blue or violet light. This causes the red, green, and blue quantum dot layers to emit display light, achieving a high color gamut full-color display. Quantum dot display panels offer advantages such as wide color gamut and high light extraction efficiency. To ensure good absorption of the excitation light by the red, green, and blue quantum dot layers, scattering particles (such as titanium dioxide (TiO2) particles) are usually doped into the red, green, and blue quantum dot layer materials. These scattering particles are typically designed to be relatively large, for example, with a diameter of 100 nm or more. Existing fabrication processes for red, green, and blue quantum dot layers usually employ inkjet printing. However, due to the large size of the scattering particles doped into the red, green, and blue quantum dot layer materials and the risk of particle aggregation during use, inkjet printing often suffers from nozzle clogging. Summary of the Invention

[0003] The purpose of this invention is to provide a method for preparing a quantum dot substrate and a quantum dot display panel, so as to solve at least one of the problems existing in the prior art.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] The first aspect of this invention provides a method for preparing a quantum dot substrate, comprising:

[0006] Provide a first substrate;

[0007] A first defining portion is formed on the first substrate. The first defining portion includes a plurality of first baffles extending along a first direction and arranged along a second direction. A gap is formed between adjacent first baffles to accommodate a first quantum dot layer, a second quantum dot layer and a third quantum dot layer.

[0008] A blocking portion extending in a first direction is formed on the top surface of the first retaining wall, and a first electrode is formed on the top of the blocking portion;

[0009] The first quantum dot layer, the second quantum dot layer, and the third quantum dot layer are formed based on the slit coating process. When one of the first quantum dot layer, the second quantum dot layer, and the third quantum dot layer is formed based on the slit coating process, the blocking part is tilted in the second direction by applying an electrical signal to the first electrode, so that the gap for accommodating the quantum dot layer being formed is exposed by the blocking part and the gap for accommodating the other two quantum dot layers is blocked by the blocking part.

[0010] Separate the blocking portion to obtain a quantum dot substrate comprising the first substrate, a first defining portion located on the first substrate, a plurality of first quantum dot layers, a plurality of second quantum dot layers, and a plurality of third quantum dot layers.

[0011] Optionally, the top surface of the first retaining wall is formed with a groove extending in a first direction, and the bottom surface of the blocking portion is formed with a first protrusion that is embedded in the groove.

[0012] Optionally, the axial cross-section of the groove extending along the first direction is trapezoidal.

[0013] Optionally, the axial cross-section of the blocking portion extending along the first direction is an inverted trapezoid.

[0014] Optionally, the material of the blocking portion is a negative photolithography material, and forming the blocking portion extending along the first direction on the top surface of the first barrier wall includes:

[0015] A barrier material layer is coated to cover the first defining portion and the exposed first substrate;

[0016] The blocking material layer is exposed and developed to form a blocking portion extending in a first direction on the top surface of the first barrier.

[0017] Optionally, the blocking portion includes a first portion close to the first retaining wall and a second portion away from the first retaining wall, the second portion being formed with a second protrusion protruding along a second direction.

[0018] Optionally, the first electrode includes a first sub-electrode and a second sub-electrode formed at both ends of the top of the second protrusion in a second direction.

[0019] Optionally, the material of the blocking portion is a negative photolithography material, and forming the blocking portion extending along the first direction on the top surface of the first barrier wall includes:

[0020] A first barrier material layer is coated to cover the first defining portion and the exposed first substrate;

[0021] A light-blocking layer is formed in the design area of ​​the second protrusion corresponding to the first blocking material layer;

[0022] A second barrier material layer is coated to cover the light-blocking layer and the exposed first barrier material layer;

[0023] The second blocking material layer and the first blocking material layer are exposed and developed to form a blocking portion extending in a first direction on the top surface of the first barrier.

[0024] Optionally, the light-blocking layer is a semi-transparent and semi-reflective layer.

[0025] Optionally, the material of the blocking part is a hydroxyl linear polyester resin.

[0026] Optionally,

[0027] After forming the first defining portion on the first substrate and before forming the blocking portion extending in the first direction on the top surface of the first barrier, the method further includes:

[0028] A metal layer is formed in the design area on the top surface of the first retaining wall that contacts the blocking part;

[0029] The separation of the blocking portion includes:

[0030] The metal layer is etched using a wet etching process;

[0031] Peel off the blocking part.

[0032] Optionally, before etching the metal layer using a wet etching process, separating the barrier portion further includes:

[0033] A first encapsulation layer is formed that covers at least the first quantum dot layer, the second quantum dot layer, and the third quantum dot layer.

[0034] A second aspect of the present invention provides a quantum dot display panel, comprising a quantum dot substrate prepared by the preparation method provided in the first aspect of the present invention, a second substrate, and a plurality of sub-pixel regions arranged in an array on the second substrate, wherein the sub-pixel regions include light-emitting units;

[0035] The quantum dot substrate is located on the side of the light-emitting unit away from the second substrate, and the light-emitting unit is located on the side of the quantum dot layer away from the first substrate. The light-emitting unit is used to emit excitation light to the first quantum dot layer, the second quantum dot layer and the third quantum dot layer to excite the first quantum dot layer, the second quantum dot layer and the third quantum dot layer to emit display light.

[0036] The beneficial effects of this invention are as follows:

[0037] The technical solution of the present invention, based on the blocking part that can be tilted to expose or cover the gap between adjacent first barrier walls, can use a slit coating process with a larger printhead opening than inkjet printing to achieve the production of red, green and blue quantum dot layers without using a mask, and finally obtain a quantum dot display panel with high color gamut full color display. Attached Figure Description

[0038] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0039] Figure 1This diagram illustrates a process flow chart of the quantum dot substrate fabrication method provided in an embodiment of the present invention.

[0040] Figures 2-20 The diagrams show typical steps in the preparation method of the quantum dot substrate provided in the embodiments of the present invention. Detailed Implementation

[0041] In this invention, "on," "formed on," and "set on" can mean that one layer is directly formed or set on another layer, or that one layer is indirectly formed or set on another layer, meaning that there are other layers between the two layers.

[0042] It should be noted that although the terms "first," "second," etc., may be used herein to describe various components, members, elements, regions, layers, and / or portions, these components, members, elements, regions, layers, and / or portions should not be limited by these terms. Rather, these terms are used to distinguish one component, member, element, region, layer, and / or portion from another. Thus, for example, the first component, first member, first element, first region, first layer, and / or first portion discussed below may be referred to as a second component, second member, second element, second region, second layer, and / or second portion without departing from the teachings of the invention.

[0043] In this invention, unless otherwise stated, the term "co-layer arrangement" refers to two layers, components, members, elements, or portions that can be formed by the same fabrication process (e.g., patterning process), and that these two layers, components, members, elements, or portions are generally formed of the same material. For example, co-layer arrangement of two or more functional layers means that these co-layered functional layers can be formed using the same material layer and the same fabrication process, thereby simplifying the fabrication process of the display substrate.

[0044] In this invention, unless otherwise stated, the term "patterning process" generally includes steps such as photoresist coating, exposure, development, etching, and photoresist stripping. The term "one-step patterning process" refers to a process of forming patterned layers, components, or parts using a single photomask.

[0045] Currently, photoluminescent quantum dot (QD) display panels are typically designed to excite the red, green, and blue quantum dot layers with short-wavelength, high-energy excitation light such as blue light, causing the red, green, and blue quantum dot layers to emit display light, thus achieving high color gamut full-color display. Quantum dot display panels have advantages such as wide color gamut and high light emission efficiency. For example, a quantum dot display panel may include an OLED substrate and a quantum dot substrate disposed on the excitation light emitting side of the OLED substrate. Such a quantum dot display panel may be called a QD-OLED display panel. The OLED substrate includes a second substrate and a plurality of sub-pixel regions arranged in an array on the second substrate. Each sub-pixel region includes an OLED light-emitting unit. The quantum dot substrate includes a quantum dot layer arranged in an array corresponding to the orthographic projection of the sub-pixel region. The quantum dot layer includes a red quantum dot layer, a green quantum dot layer and a blue quantum dot layer. According to the pixel design of the QD-OLED display panel, the quantum dot substrate may also include a red quantum dot layer, a green quantum dot layer and a blue quantum dot layer that extend along a first direction (e.g., column direction Y) and are arranged, for example, periodically along a second direction (e.g., row direction X).

[0046] The red quantum dot layer can emit red light when excited by short-wavelength, high-energy excitation light such as blue or violet light emitted from the corresponding OLED light-emitting unit. The green quantum dot layer can emit green light when excited by short-wavelength, high-energy excitation light such as blue or violet light emitted from the corresponding OLED light-emitting unit. The blue quantum dot layer can emit blue light when excited by short-wavelength, high-energy excitation light such as blue or violet light emitted from the corresponding OLED light-emitting unit. To ensure that the red, green, and blue quantum dot layers can absorb the excitation light well, scattering particles (such as titanium dioxide TiO2 particles) are usually doped into the red, green, and blue quantum dot layer materials. The size of the scattering particles is usually designed to be relatively large, for example, with a diameter of more than 100 nm. Existing fabrication processes for red, green, and blue quantum dot layers typically employ inkjet printing. For example, a quantum dot layer definition area is first formed on a quantum dot substrate. Then, a three-stage inkjet printing process is used to sequentially coat the corresponding openings in the quantum dot layer definition area with a mixture of red quantum dots and scattering particles, a mixture of green quantum dots and scattering particles, and a mixture of blue quantum dots and scattering particles, thus forming the red, green, and blue quantum dot layers. However, because the scattering particles in the red, green, and blue quantum dot layer materials (i.e., the mixtures formed by red, green, and blue quantum dots and scattering particles, respectively) are relatively large and there is a risk of particle aggregation during use, inkjet printing nozzle clogging is a frequent problem.

[0047] In view of this, such as Figure 1 As shown, one embodiment of the present invention provides a method for preparing a quantum dot substrate, comprising the following steps:

[0048] S110 provides a first substrate.

[0049] In this context, the first substrate serves as the carrier structure for the quantum dot substrate. In a specific example, the first substrate can be made of a material with high light transmittance, such as glass or quartz, and the thickness of the first substrate is, for example, set between 0.3 mm and 1.5 mm.

[0050] S120, A black matrix layer (BM) is formed in the first barrier design region on the first substrate.

[0051] The black matrix layer is used to prevent light crosstalk in the final quantum dot substrate. It is understood that step S120 is an optional step in this embodiment, and the black matrix layer formed in step S120 is an optional structure in this embodiment.

[0052] S130. A first defining portion is formed on the first substrate. The first defining portion includes a plurality of first baffles (which may be referred to as line banks) extending along a first direction and arranged along a second direction. A gap is formed between adjacent first baffles to accommodate the red quantum dot layer, the green quantum dot layer and the blue quantum dot layer.

[0053] It is understandable that there are gaps between adjacent first retaining walls, which means that multiple first retaining walls are arranged at intervals along the second direction.

[0054] For example, such as Figure 2 and Figure 3 As shown, step S130 includes forming a first defining portion on a first substrate 101. The first defining portion includes a plurality of first baffles 103 extending along a first direction and arranged along a second direction, wherein the orthographic projection of the first baffles 103 on the first substrate 101 is covered by the orthographic projection of the black matrix layer 102 on the first substrate 101.

[0055] Figure 3 The top-view diagram shows the orthographic correspondence between the first barrier 103 and, for example, the pixel defining layer 201 in the OLED substrate of a QD-OLED display panel. Figure 3 As shown, the pixel defining layer 201 in the OLED substrate is in a grid shape, and the light-emitting units are formed in the openings of the grid-shaped pixel defining layer 201. The first direction is the column direction Y, and the second direction is the row direction X. The gaps between adjacent first barrier walls 103 are used to accommodate red quantum dot layers, green quantum dot layers, and blue quantum dot layers extending along the first direction, for example... Figure 3In the middle, the gap between the first adjacent first barrier 103 from the left is used to accommodate the red quantum dot layer extending along the first direction, the gap between the second adjacent first barrier 103 from the left is used to accommodate the green quantum dot layer extending along the first direction, the gap between the third adjacent first barrier 103 from the left is used to accommodate the blue quantum dot layer extending along the first direction, the gap between the fourth adjacent first barrier 103 from the left is used to accommodate the red quantum dot layer extending along the first direction, and the gap between the fifth adjacent first barrier 103 from the left is used to accommodate the green quantum dot layer extending along the first direction. That is, the red quantum dot layer, green quantum dot layer and blue quantum dot layer that are subsequently formed extending along the first direction are periodically arranged along the second direction.

[0056] In a specific example, the material of the first barrier is, for example, acrylic, epoxy resin, etc., which can effectively prevent crosstalk between excitation lights. For example, scattering or reflecting particles can be added to the resin, or black dye can be used to form the light-absorbing first barrier.

[0057] In a specific example, the length of the first barrier in the second direction is designed to be 10μm to 35μm, and the thickness of the first barrier is designed to be 5μm to 15μm. The thickness of the first barrier determines the thickness of the quantum dot layer subsequently formed in the gap between adjacent first barriers, and its design mainly considers the absorption efficiency of the quantum dot layer material. The length of the gap between adjacent first barriers in the second direction is designed to be 10μm to 30μm. The design of the length of the gap between adjacent first barriers in the second direction is to consider the shielding effect of the blocking part when the quantum dot layer material is coated later. If the gap is too wide, it is more difficult to achieve the designed closure effect. This can be better understood according to the explanation of the following steps. For example, Figure 2 As shown, the length of the first retaining wall 103 in the second direction X (i.e. Figure 2 The width of the first retaining wall 103 is 10 μm, the thickness (or height) of the first retaining wall 103 is 10 μm, and the length of the gap between adjacent first retaining walls 103 in the second direction is 15 μm. It should be noted that... Figure 2 The structure shown may differ visually from its actual size proportions; the same applies to subsequent figures.

[0058] In one possible implementation, step S130 further includes: forming a groove extending in a first direction on the top surface of the first retaining wall.

[0059] The groove formed by this implementation allows the subsequently formed blocking part to better integrate with the first retaining wall, increasing the stability of the integration between the blocking part and the first retaining wall. In particular, it can prevent the blocking part from detaching from the first retaining wall when it is tilted. This can be better understood according to the explanation of the following steps.

[0060] In a specific example, Figure 2 Based on the structure shown, the structure formed by this implementation is as follows: Figure 4 As shown, the top surface of the first retaining wall 103 has a groove 1031 extending in the first direction.

[0061] In one possible implementation, the axial cross-section of the groove extending along the first direction is a trapezoid.

[0062] In a specific example, Figure 2 Based on the structure shown, the structure formed by this implementation is as follows: Figure 4 As shown, the axial cross-section of the groove 1031 extending along the first direction Y is a trapezoid, wherein, combined with Figure 3 It is understood that the axial section of the groove 1031 extending along the first direction Y is the section of the groove 1031 parallel to the first plane, and the first plane is perpendicular to the first substrate 101 and parallel to the second direction X.

[0063] In one possible implementation, step S130 further includes forming a metal layer in the design area on the top surface of the first retaining wall that contacts the blocking portion.

[0064] The metal layer formed in this implementation can be called a stripping layer in terms of its function. It allows for the convenient separation of the blocking part after the quantum dot layer is formed. This can be better understood by referring to the following steps.

[0065] In a specific example, Figure 4 Based on the structure shown, the structure formed by this implementation is as follows: Figure 5 As shown, a metal layer 104 is formed on the top surface of the first retaining wall 103, wherein the metal layer 104 covers the bottom and sidewalls of the groove 1031 and extends to the area around the groove 1031 on the top surface of the first retaining wall 103.

[0066] In a specific example, by Figure 2 The structure shown is obtained Figure 4 The structure shown and its components Figure 4 The structure shown is obtained Figure 5 The process flow of the structure shown is as follows:

[0067] First, a boundary layer material is deposited on a first substrate. Then, a first barrier 103 is fabricated by exposure and development. Next, exposure is performed again, and by using a dry etching process and adjusting the gas flow rate and gas ratio, a groove 1031 with an axial cross-section of a positive trapezoid is formed on the top surface of the first barrier 103. After the groove 1031 with an axial cross-section of a positive trapezoid is fabricated, a metal layer 104 is fabricated by evaporation using a fine metal mask (FMM). Alternatively, after the groove 1031 with an axial cross-section of a positive trapezoid is fabricated, the metal layer 104 can also be fabricated by a sputtering deposition followed by exposure and development process.

[0068] S140, A blocking portion extending in a first direction is formed on the top surface of the first retaining wall, and a first electrode is formed on the top of the blocking portion.

[0069] In one possible implementation, in this embodiment, the blocking portion formed in step S140 includes two structures, and correspondingly, step S140 includes two processes corresponding to these two structures. These will be described separately below.

[0070] For the blocking part of the first structure:

[0071] The axial cross section of the blocking part of the first structure extending along the first direction is approximately rectangular.

[0072] In a specific example, see, for example Figure 6 and Figure 7 :like Figure 7 As shown, the axial cross-section of the first type of blocking portion 1051 extending along the first direction is approximately rectangular. In a specific example, the axial cross-section of the first type of blocking portion 1051 extending along the first direction Y is approximately rectangular, wherein, combined with Figure 3 It is understood that the axial section of the first structure blocking portion 1051 extending along the first direction Y is the section of the blocking portion 1051 parallel to the first plane, the first plane being perpendicular to the first substrate 101 and parallel to the second direction X.

[0073] In one possible implementation, the first electrode formed at the top of the barrier portion of the first structure is located at the center of the top surface of the barrier portion of the first structure. This facilitates the positive and negative tilting of the barrier portion of the first structure in the second direction during the subsequent step of forming the quantum dot layer, which can be better understood from the description of the following steps.

[0074] In a specific example, such as Figure 7As shown, the first electrode 1061 formed on the top of the blocking portion 1051 of the first structure is located at the center of the top surface of the blocking portion 1051 of the first structure. It can be understood that the first electrode 1061 also extends along the first direction X, and the fact that the first electrode 1061 is located at the center of the top surface of the blocking portion 1051 of the first structure can be understood as the first electrode 1061 being located at the center of the top surface of the blocking portion 1051 of the first structure in the second direction Y.

[0075] In one possible implementation, the axial cross-section of the blocking portion of the first structure extending along the first direction is an inverted trapezoid. This makes it easier for the blocking portion of the first structure to tilt in the second direction during the subsequent step of forming the quantum dot layer, as can be better understood from the description of the following steps.

[0076] In one possible implementation, the material of the blocking portion of the first structure is a negative photolithography material, and the blocking portion forming the first structure includes:

[0077] A barrier material layer is coated to cover the first defining portion and the exposed first substrate;

[0078] The barrier material layer is exposed and developed to form a barrier extending in a first direction on the top surface of the first barrier.

[0079] This implementation can effectively form the first type of barrier. Since the material of the barrier in the first type of structure is a negative photolithography material, when the barrier material layer is exposed and developed, the exposure amount or light irradiation amount decreases from top to bottom, which naturally results in the axial cross-section of the barrier in the first type of structure proposed by the aforementioned implementation being an inverted trapezoid.

[0080] In one possible implementation, when a groove extending in a first direction is formed on the top surface of the first retaining wall, the bottom surface of the blocking portion of the first structure has a first protrusion that is embedded in the groove.

[0081] Understandably, based on the manufacturing process of the first structure of the blocking part described above, when a groove extending in the first direction is formed on the top surface of the first barrier wall, the bottom surface of the resulting first structure of the blocking part will naturally bulge to form a first protrusion embedded in the groove. The first structure of the blocking part formed by this implementation can better integrate with the first barrier wall, increasing the stability of the integration between the blocking part and the first barrier wall. In particular, it can prevent the blocking part from detaching from the first barrier wall when the blocking part is tilted in the subsequent step of forming the quantum dot layer. This can be better understood according to the explanation of the following steps.

[0082] In a specific example, Figure 5 Based on the structure shown, the process flow for fabricating the blocking part of the first structure is as follows:

[0083] A barrier material layer 1051' is applied to cover the first defining portion and the exposed first substrate 101, resulting in the following: Figure 6 The structure shown has a blocking material layer 1051' that is a negative photolithography material, which is a resin material with certain light-blocking properties.

[0084] The barrier material layer 1051' is exposed and developed to form a first-structure barrier 1051 extending in a first direction on the top surface of the first barrier 103;

[0085] A first electrode 1061 is formed at the center of the top surface of the blocking portion 1051 in the first structure, resulting in... Figure 7 The structure shown in the diagram, wherein the first electrode 1061 functions as a traction electrode that is inclined in the second direction for the blocking portion 1051 of the first structure in the subsequent step of forming the quantum dot layer.

[0086] In a specific example, see Figure 7 As shown, the axial cross-section of the first-structure blocking portion 1051 extending along the first direction is approximately rectangular. Its bottom surface protrudes to form a first protrusion 10511 that embeds into the groove on the top surface of the first baffle 103. The first electrode 1061 is formed at the center of the top surface of the first-structure blocking portion 1051 in the second direction Y. For example, the thickness of the first-structure blocking portion is designed to be 10μm to 15μm (e.g., 15μm), the length of the bottom of the first-structure blocking portion in the second direction is designed to be 0.5μm to 0.7μm, and the length of the top of the first-structure blocking portion in the second direction is designed to be approximately 10μm to 35μm, similar to the length of the first baffle.

[0087] The first electrode can be made of transparent electrode materials, such as indium tin oxide (ITO) or indium zinc oxide (IZO), or it can be made of metallic electrode materials, such as aluminum (Al) or molybdenum (Mo). The length of the first electrode in the second direction is designed to be 5 μm to 10 μm, and the thickness is... ( (Indicates angstrom), connected to an external controller, which can scan the first electrode line by line.

[0088] Furthermore, it is understood that the blocking portion of the first structure described above can also be formed through a printing process.

[0089] In one possible implementation, the material of the barrier portion of the first structure is a hydroxyl linear polyester resin. Hydroxyl linear polyester resin has high toughness, ensuring that the barrier portion of the first structure has relatively strong toughness. Simultaneously, F atoms can be excited on the resin chain, giving it a low surface energy. This prevents the quantum dot layer material from adhering to the sidewalls of the barrier portion of the first structure during the subsequent quantum dot layer formation process. This will be better understood according to the explanation of the following steps.

[0090] The second type of blocking part:

[0091] The second type of barrier extending along the first direction includes a first part close to the first barrier and a second part away from the first barrier, the second part having a second protrusion protruding along the second direction. Compared to the first type of barrier, the top of the second type of barrier is wider in the second direction, resulting in better masking in the subsequent quantum dot layer formation step and allowing for larger pixel sizes, which can be better understood from the explanation of the following steps.

[0092] In one possible implementation, the first electrode formed on the top of the barrier portion of the second structure includes a first sub-electrode and a second sub-electrode formed at both ends of the top of the second protrusion in the second direction. Further, the first and second sub-electrodes are respectively formed at both ends of the top surface of the second protrusion in the second direction. Because the top of the barrier portion of the second structure is wider in the second direction, this electrode arrangement of the barrier portion of the second structure is more conducive to the positive and negative tilting of the barrier portion in the second direction during the subsequent quantum dot layer formation step, which can be better understood from the description of the following steps.

[0093] In one possible implementation, the material of the blocking portion of the second structure is a negative photolithography material, and the blocking portion forming the second structure includes:

[0094] A first barrier material layer is coated to cover the first defining portion and the exposed first substrate;

[0095] A light-blocking layer is formed in the design area of ​​the second protrusion corresponding to the first blocking material layer;

[0096] A second barrier material layer is coated to cover the light-blocking layer and the exposed first barrier material layer;

[0097] The second barrier material layer and the first barrier material layer are exposed and developed to form a barrier extending in a first direction on the top surface of the first barrier.

[0098] This method allows for the effective formation of the second type of barrier portion through a single exposure and development process.

[0099] In one possible implementation, when a groove extending in a first direction is formed on the top surface of the first retaining wall, the bottom surface of the second type of blocking portion is formed with a first protrusion that is embedded in the groove.

[0100] Understandably, based on the manufacturing process of the second type of barrier described above, when a groove extending in the first direction is formed on the top surface of the first barrier, the bottom surface of the resulting second type of barrier will naturally bulge to form a first protrusion embedded in the groove. The second type of barrier formed by this implementation can better integrate with the first barrier, increasing the stability of the connection between the barrier and the first barrier. Especially in the subsequent step of forming the quantum dot layer, it can prevent the barrier from detaching from the first barrier when tilted, as can be better understood from the explanation of the following steps.

[0101] In one possible implementation, the light-blocking layer is a semi-transparent, semi-reflective layer. This enhances the bonding strength between the first and second parts. Alternatively, the light-blocking layer can also be an absorbing layer or a reflective layer.

[0102] In a specific example, Figure 5 Based on the structure shown, the process flow for fabricating the second type of blocking part is as follows:

[0103] A first barrier material layer 10521' is applied to cover the first defining portion and the exposed first substrate 101, resulting in the following: Figure 8 As can be understood from the structure shown, drying and pre-baking should be performed after coating the first barrier material layer 10521'.

[0104] A semi-transparent, semi-reflective layer 107 is formed in the design area corresponding to the second protrusion of the first blocking material layer 10521', resulting in... Figure 9 The structure shown can be fabricated using a fine metal mask (FMM) to create a semi-transparent and semi-reflective layer 107 of materials such as silver (Ag), magnesium (Mg), and aluminum (AL).

[0105] A second barrier material layer 10522' is coated over the semi-transparent, semi-reflective layer 107 and the exposed first barrier material layer 10521' to obtain the following: Figure 10 As can be understood from the structure shown, drying and pre-baking should be performed after coating the second barrier material layer 10522'.

[0106] The second barrier material layer 10522' and the first barrier material layer 10521' are exposed and developed to form a second type of barrier extending in the first direction on the top surface of the first barrier wall, wherein the exposure process is as follows: Figure 11As shown, the opening of the exposure mask corresponds to the second shape of the blocking part in the second structure. Due to the blocking of light by the semi-transparent and semi-reflective layer 107, the exposed area of ​​the first blocking part material layer 10521' becomes smaller, thereby obtaining the desired result. Figure 12 The blocking portion 1052 shown includes a first portion 10521 and a second portion 10522;

[0107] In the second type of structure, a first electrode 1062, including a first sub-electrode 10621 and a second sub-electrode 10622, is formed at both ends of the top surface of the blocking portion 1051 in the second direction, resulting in the following: Figure 12 The structure shown in the diagram, wherein the first sub-electrode 10621 and the second sub-electrode 10622 serve as traction electrodes for the second structure, which are inclined in the second direction, in the subsequent step of forming the quantum dot layer.

[0108] In a specific example, see Figure 12 As shown, the second-structure blocking portion 1052 extending along the first direction includes a lower first portion 10521 and an upper second portion 10522. The bottom surface of the first portion 10521 has a first protrusion 10523 that is embedded in the groove on the top surface of the first baffle 103. It can also be understood that the second-structure blocking portion 1052 includes the first portion 10521, the second portion 10522, and the first protrusion 10523. The first sub-electrode 10621 and the second sub-electrode 10622 are respectively formed at both ends of the top surface of the second portion 10522 in the second direction Y. For example, in the second-structure blocking portion, the thickness of the first portion is designed to be 5μm to 10μm, the length of the first portion in the second direction is designed to be 4μm to 10μm, the thickness of the second portion is designed to be 3μm to 8μm, and the length of the second portion including the second protrusions on both sides in the second direction is designed to be 10μm to 15μm.

[0109] Furthermore, it is understood that the blocking portion of the second structure described above can also be formed through a printing process.

[0110] In one possible implementation, the material of the barrier portion in the second structure is a hydroxyl linear polyester resin. That is, for the barrier portion in the second structure, the materials of the first and second portions are both hydroxyl linear polyester resins. Hydroxyl linear polyester resins have high toughness, ensuring that the barrier portion in the first structure has relatively strong toughness. Simultaneously, F atoms can be excited on the resin chains, giving them a low surface energy. This prevents the quantum dot layer material from adhering to the sidewalls of the barrier portion in the first structure during the subsequent quantum dot layer formation process, as will be better understood from the following explanations. Furthermore, the material of the second portion in the barrier portion of the second structure can also be an elastic resin with better rigidity than hydroxyl linear polyester resin.

[0111] Thus, we have obtained the following: Figure 7 or Figure 12 The substrate structure shown includes a first substrate, a first defining portion formed on the first substrate, and a plurality of blocking portions. A black matrix layer extends along a first direction and is spaced apart along a second direction. The first defining portion includes a plurality of first barrier walls extending along the first direction and arranged along the second direction. Gaps for accommodating red, green, and blue quantum dot layers are formed between adjacent first barrier walls. The plurality of blocking portions extend along the first direction and are respectively disposed on the top surface of the plurality of first barrier walls. A first electrode is disposed on the top of each blocking portion. Furthermore, the substrate structure may also include a plurality of black matrix layers extending along the first direction and spaced apart along the second direction. The orthographic projection of the first barrier walls onto the first substrate is covered by the orthographic projection of the black matrix layers onto the first substrate. Subsequent steps (i.e., step S150 below) can be performed based on this substrate structure to fabricate a quantum dot substrate.

[0112] S150. A red quantum dot layer, a green quantum dot layer, and a blue quantum dot layer are formed respectively based on a slit coating process. When one of the red quantum dot layer, the green quantum dot layer, and the blue quantum dot layer is formed based on the slit coating process, an electrical signal is applied to the first electrode to tilt the blocking part in the second direction, so that the gap for accommodating the quantum dot layer being formed is exposed by the blocking part and the gap for accommodating the other two quantum dot layers is blocked by the blocking part.

[0113] In a specific example, the red, green, and blue quantum dot layers are arranged periodically in the second direction, for instance. For a set of red, green, and blue quantum dot layers, based on... Figure 7 The substrate structure shown, including the blocking portion 1051 of the first structure, is used to form red quantum dot layers, green quantum dot layers, and blue quantum dot layers respectively using a slot coating process, for example:

[0114] First, such as Figure 13 As shown, Figure 13In the gaps between the three adjacent first barrier walls 103 from left to right, the two side gaps are used to form green and blue quantum dot layers respectively, and the middle gap is used to form a red quantum dot layer. A positive voltage signal can be applied to the first electrode 1061 on the first barrier 1051 from left to right, and a negative voltage signal can be applied to the first electrode 1061 on the second barrier 1051, the third barrier 1051, and the fourth barrier 1051 from left to right. This causes the tops of the first and second blocking portions 1051 from left to right to attract each other and tilt under the influence of the electric field, thus shielding the left gap. Similarly, the tops of the third and fourth blocking portions 1051 from left to right attract each other and tilt under the influence of the electric field, thus shielding the right gap. Simultaneously, the tilting of the second and third blocking portions 1051 from left to right exposes the middle gap. In this way, red quantum dot layer material 1081' can be coated on the middle gap using a slit coating process without using a mask. It should be noted that: firstly, this can be achieved by sequentially applying electricity to the first electrode 1051 in the second direction X. Figure 13 The obstruction section is tilted as shown. Thus, when a positive voltage signal is applied to the first electrode 1061 on the third obstruction section 1051 from left to right, since the second obstruction section 1051 has already tilted to the left, the third obstruction section 1051 and the second obstruction section 1051 will no longer tilt due to mutual attraction of the electric field force. Secondly, taking the first and second obstruction sections 1051 from left to right tilting due to mutual attraction at their tops under the action of the electric field force, thereby shielding the left gap, as an example, since the red quantum dot layer material 1081'—a mixed solution containing red quantum dots and scattering particles—has surface tension, for example, it cannot enter if the deflection is greater than 10 degrees. Therefore, the first and second obstruction sections 1051, as... Figure 13 As shown, it is not necessary to completely close the gap to create a shielding effect on the left side.

[0115] After coating the red quantum dot layer material 1081', the electrical signal applied to each first electrode 1061 is first removed, and each blocking part 1051 is restored to its initial non-tilted state. Then, the red quantum dot layer material 1081' is cured to form the red quantum dot layer 1081.

[0116] Then, as Figure 14 As shown, Figure 14In the gaps between the three adjacent first barrier walls 103 from left to right, the two side gaps are used to form red and blue quantum dot layers respectively, and the middle gap is used to form a green quantum dot layer. A positive voltage signal can be applied to the first electrode 1061 on the first barrier 1051 from left to right, and a negative voltage signal can be applied to the first electrode 1061 on the second barrier 1051, the third barrier 1051, and the fourth barrier 1051 from left to right. The first and second blocking parts 1051 from left to right are attracted to each other and tilted under the action of the electric field, thus shielding the left gap. The third and fourth blocking parts 1051 from left to right are attracted to each other and tilted under the action of the electric field, thus shielding the right gap. At the same time, the tilting of the second and third blocking parts 1051 from left to right exposes the middle gap. In this way, green quantum dot layer material 1082' can be coated on the middle gap based on the slit coating process without using a mask.

[0117] After coating the green quantum dot layer material 1082', the electrical signal applied to each first electrode 1061 is first removed, and each blocking part 1051 is restored to its initial non-tilted state. Then, the green quantum dot layer material 1082' is cured to form the green quantum dot layer 1082.

[0118] Finally, as Figure 15 As shown, Figure 15 In the gaps between the three adjacent first barrier walls 103 from left to right, the two side gaps are used to form red and green quantum dot layers respectively, and the middle gap is used to form a blue quantum dot layer. A positive voltage signal can be applied to the first electrode 1061 on the first barrier 1051 from left to right, and a negative voltage signal can be applied to the first electrode 1061 on the second barrier 1051, the third barrier 1051, and the fourth barrier 1051 from left to right. The first and second blocking parts 1051 from left to right are attracted to each other and tilted under the action of the electric field, thus shielding the left gap. The third and fourth blocking parts 1051 from left to right are attracted to each other and tilted under the action of the electric field, thus shielding the right gap. At the same time, the tilting of the second and third blocking parts 1051 from left to right exposes the middle gap. In this way, blue quantum dot layer material 1083' can be coated in the middle gap based on the slit coating process without using a mask.

[0119] After coating the blue quantum dot layer material 1083', the electrical signal applied to each first electrode 1061 is first removed, and each blocking part 1051 is restored to its initial non-tilted state. Then, the blue quantum dot layer material 1083' is cured to form the blue quantum dot layer 1083.

[0120] In another specific example, red, green, and blue quantum dot layers are arranged periodically, for example, in the second direction. For a set of red, green, and blue quantum dot layers, based on... Figure 12 The substrate structure shown, including the barrier portion 1052 of the second structure, is processed by forming red quantum dot layers, green quantum dot layers, and blue quantum dot layers respectively using a slot coating process, for example:

[0121] First, such as Figure 16 As shown, Figure 16 In the gaps between the three adjacent first barrier walls 103 from left to right, the two side gaps are used to form green quantum dot layers and blue quantum dot layers respectively, and the middle gap is used to form a red quantum dot layer. By applying a positive voltage signal to the left first sub-electrode 10621 and a negative voltage signal to the right first sub-electrode 10622 on the first to fourth barrier parts 1061 from left to right in a row-by-row manner from left to right, the tops of the first and second barrier parts 1061 from left to right attract each other under the action of the electric field force and tilt, thereby shielding the left gap. The tops of the third and fourth barrier parts 1061 from left to right attract each other under the action of the electric field force and tilt, thereby shielding the right gap. At the same time, the tilting of the second and third barrier parts 1061 from left to right exposes the middle gap. In this way, the red quantum dot layer material 1081' can be coated in the middle gap based on the slot coating process without using a mask.

[0122] After coating the red quantum dot layer material 1081', the electrical signal applied to each first electrode 1061 is first removed, and each blocking part 1061 is restored to its initial non-tilted state. Then, the red quantum dot layer material 1081' is cured to form the red quantum dot layer 1081.

[0123] Then, as Figure 17 As shown, Figure 17In the gaps between the three adjacent first barrier walls 103 from left to right, the two side gaps are used to form red and blue quantum dot layers respectively, and the middle gap is used to form a green quantum dot layer. A positive voltage signal is applied to the left first sub-electrode 10621 and the right first sub-electrode 10622 on the first to fourth barrier parts 1061 from left to right by applying electricity row by row from left to right. This causes the tops of the first and second barrier parts 1061 from left to right to attract each other and tilt under the action of the electric field, thereby shielding the left gap. The tops of the third and fourth barrier parts 1061 from left to right to attract each other and tilt under the action of the electric field, thereby shielding the right gap. At the same time, the tilting of the second and third barrier parts 1061 from left to right exposes the middle gap. In this way, the green quantum dot layer material 1082' can be coated in the middle gap by slit coating process without using a mask.

[0124] After coating the green quantum dot layer material 1082', the electrical signal applied to each first electrode 1061 is first removed, and each blocking part 1061 is restored to its initial non-tilted state. Then, the green quantum dot layer material 1082' is cured to form the green quantum dot layer 1082.

[0125] Finally, as Figure 18 As shown, Figure 18 In the gaps between the three adjacent first barrier walls 103 from left to right, the two side gaps are used to form red and green quantum dot layers respectively, and the middle gap is used to form a blue quantum dot layer. A positive voltage signal is applied to the left first sub-electrode 10621 and the right first sub-electrode 10622 on the first to fourth barrier parts 1061 from left to right by applying electricity row by row from left to right. This causes the tops of the first and second barrier parts 1061 from left to right to attract each other and tilt under the action of the electric field, thereby shielding the left gap. The tops of the third and fourth barrier parts 1061 from left to right to attract each other and tilt under the action of the electric field, thereby shielding the right gap. At the same time, the tilting of the second and third barrier parts 1061 from left to right exposes the middle gap. In this way, the blue quantum dot layer material 1083' can be coated in the middle gap by slit coating process without using a mask.

[0126] After coating the blue quantum dot layer material 1083', the electrical signal applied to each first electrode 1061 is first removed, and each blocking part 1061 is restored to its initial non-tilted state. Then, the blue quantum dot layer material 1083' is cured to form the blue quantum dot layer 1083.

[0127] In summary, this embodiment is designed as follows: Figure 7 or Figure 12 The substrate structure shown, based on the blocking portion 1051 or blocking portion 1052 which can be tilted to expose or cover the gap between adjacent first barrier walls 103, can use a slit coating process with a larger printhead opening than inkjet printing to achieve the fabrication of red, green and blue quantum dot layers without using a mask.

[0128] S160, Separate the blocking part to obtain a quantum dot substrate. The quantum dot substrate includes a first substrate, a first defining part located on the first substrate, a quantum dot substrate with multiple red quantum dot layers, multiple green quantum dot layers and multiple blue quantum dot layers.

[0129] In one possible implementation, if a metal layer is formed in the design area on the top surface of the first retaining wall that contacts the blocking portion, step S160 further includes:

[0130] Metal layers are etched using a wet etching process;

[0131] Peel off the blocking part.

[0132] Therefore, the blocking part can be easily separated.

[0133] In one possible implementation, before etching the metal layer using a wet etching process, step S160 further includes:

[0134] A first encapsulation layer is formed, covering at least a red quantum dot layer, a green quantum dot layer, and a blue quantum dot layer. This allows the already formed red, green, and blue quantum dot layers to be protected during the etching of the metal layer using a wet etching process.

[0135] In a specific example, based on Figure 18 The structure shown is such that, after first removing the electrical signal applied to each first electrode 1061, each blocking portion 1061 returns to its initial non-tilted state, the blue quantum dot layer material is cured to form the blue quantum dot layer. After this, a first encapsulation layer 109 for blocking water and oxygen can be deposited, for example, using a chemical vapor deposition (CVD) process. For example, the thickness is... In between, we obtained such as Figure 19 The structure shown is followed by etching the metal layer 104 using a wet etching process. This allows the barrier portion 1052 to be easily peeled off. After peeling off the barrier portion 1052, a second encapsulation layer 110 can be formed using, for example, a chemical vapor deposition process to increase the water and oxygen barrier capability of the quantum dot substrate. The materials of the first encapsulation layer 109 and the second encapsulation layer 110 are, for example, silicon dioxide (SiO2) for one and silicon nitride (SiN) for the other. x ).

[0136] Thus, we have obtained the following: Figure 20 The quantum dot substrate shown includes a first substrate 101, a first defining portion located on the first substrate 101, a plurality of red quantum dot layers 1081, a plurality of green quantum dot layers 1082, and a plurality of blue quantum dot layers 1083. The first defining portion includes first barrier walls 103 extending along a first direction and arranged along a second direction. The red quantum dot layers 1081, green quantum dot layers 1082, and blue quantum dot layers 1083 are disposed in the gaps between adjacent first barrier walls 103. Furthermore, the quantum dot substrate may also include a first encapsulation layer 109 and a second encapsulation layer 110 for encapsulating the red quantum dot layers 1081, green quantum dot layers 1082, and blue quantum dot layers 1083, for example... Figure 20 As shown, a groove extending along a first direction is formed on the top surface of the first barrier 103. This quantum dot substrate can then be placed on the excitation light emitting side of, for example, an OLED substrate to obtain a quantum dot display panel.

[0137] Another embodiment of the present invention provides a quantum dot display panel, including a quantum dot substrate, a second substrate, and a plurality of sub-pixel regions arranged in an array on the second substrate, wherein the sub-pixel regions include light-emitting units.

[0138] The quantum dot substrate can be prepared by the quantum dot substrate preparation method provided in the foregoing embodiments. The quantum dot substrate includes a first substrate, a first defining portion located on the first substrate, a plurality of red quantum dot layers, a plurality of green quantum dot layers and a plurality of blue quantum dot layers. The first defining portion includes a first barrier extending along a first direction and arranged along a second direction. The red quantum dot layers, green quantum dot layers and blue quantum dot layers are disposed in the gap between adjacent first barrier layers.

[0139] In the quantum dot display panel provided in this embodiment, the quantum dot substrate is located on the side of the light-emitting unit away from the second substrate, and the light-emitting unit is located on the side of the quantum dot layer away from the first substrate. The light-emitting unit is used to emit excitation light to the red quantum dot layer, the green quantum dot layer and the blue quantum dot layer to excite the red quantum dot layer, the green quantum dot layer and the blue quantum dot layer to emit display light.

[0140] Another embodiment of the present invention provides a quantum dot display device, including the aforementioned quantum dot display panel. The quantum dot display device can be any product or component with display functionality, such as a mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, or navigator; this embodiment does not limit the scope of the application.

[0141] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A method of fabricating a quantum dot substrate, comprising: include: ​ Provide a first substrate; A first defining portion is formed on the first substrate. The first defining portion includes a plurality of first baffles extending along a first direction and arranged along a second direction. A gap is formed between adjacent first baffles to accommodate a first quantum dot layer, a second quantum dot layer and a third quantum dot layer. A blocking portion extending in a first direction is formed on the top surface of the first retaining wall, and a first electrode is formed on the top of the blocking portion; A first quantum dot layer, a second quantum dot layer, and a third quantum dot layer are formed respectively using a slit coating process. When forming one of the first quantum dot layer, the second quantum dot layer, and the third quantum dot layer using the slit coating process, an electrical signal is applied to the first electrode to tilt the blocking part in the second direction, so that the gap for accommodating the quantum dot layer being formed is exposed by the blocking part and the gap for accommodating the other two quantum dot layers is blocked by the blocking part; opposite electrical signals are applied to adjacent first electrodes. Separate the blocking portion to obtain a quantum dot substrate comprising the first substrate, a first defining portion located on the first substrate, a plurality of first quantum dot layers, a plurality of second quantum dot layers, and a plurality of third quantum dot layers.

2. The production method according to claim 1, characterized by, The top surface of the first retaining wall has a groove extending in a first direction, and the bottom surface of the blocking part has a first protrusion that is embedded in the groove.

3. The preparation method according to claim 2, characterized in that, The axial cross-section of the groove extending along the first direction is a trapezoid.

4. The method of claim 1, wherein, The axial cross-section of the blocking portion extending along the first direction is an inverted trapezoid.

5. The production method according to claim 4, characterized by, The material of the blocking portion is a negative photolithography material, and forming the blocking portion extending along the first direction on the top surface of the first barrier wall includes: A barrier material layer is coated to cover the first defining portion and the exposed first substrate; The blocking material layer is exposed and developed to form a blocking portion extending in a first direction on the top surface of the first barrier.

6. The method of claim 1, wherein, The blocking portion includes a first portion close to the first retaining wall and a second portion away from the first retaining wall, the second portion having a second protrusion protruding along a second direction.

7. The preparation method according to claim 6, characterized in that, The first electrode includes a first sub-electrode and a second sub-electrode formed at both ends of the top of the second protrusion in a second direction.

8. The preparation method according to claim 6, characterized in that, The material of the blocking portion is a negative photolithography material, and forming the blocking portion extending along the first direction on the top surface of the first barrier wall includes: A first barrier material layer is coated to cover the first defining portion and the exposed first substrate; A light-blocking layer is formed in the design area of ​​the second protrusion corresponding to the first blocking material layer; A second barrier material layer is coated to cover the light-blocking layer and the exposed first barrier material layer; The second blocking material layer and the first blocking material layer are exposed and developed to form a blocking portion extending in a first direction on the top surface of the first barrier.

9. The production method according to claim 8, characterized by, The light-blocking layer is a semi-transparent and semi-reflective layer.

10. The production method according to any one of claims 1 to 9, characterized by, The material of the blocking part is hydroxyl linear polyester resin.

11. The preparation method according to any one of claims 1-9, characterized in that, After forming the first defining portion on the first substrate and before forming the blocking portion extending in the first direction on the top surface of the first barrier, the method further includes: A metal layer is formed in the design area on the top surface of the first retaining wall that contacts the blocking part; The separation of the blocking portion includes: The metal layer is etched using a wet etching process; Peel off the blocking part.

12. The method of claim 11, wherein, Before etching the metal layer using a wet etching process, separating the barrier portion further includes: A first encapsulation layer is formed that covers at least the first quantum dot layer, the second quantum dot layer, and the third quantum dot layer.

13. A quantum dot display panel, characterized by, The invention includes a quantum dot substrate prepared by the preparation method according to any one of claims 1-12, a second substrate, and a plurality of sub-pixel regions arranged in an array on the second substrate, wherein the sub-pixel regions include light-emitting units; The quantum dot substrate is located on the side of the light-emitting unit away from the second substrate, and the light-emitting unit is located on the side of the quantum dot layer away from the first substrate. The light-emitting unit is used to emit excitation light to the first quantum dot layer, the second quantum dot layer and the third quantum dot layer to excite the first quantum dot layer, the second quantum dot layer and the third quantum dot layer to emit display light.

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