Display substrate and manufacturing method thereof, and display device

Abstract

A display substrate comprises: a base substrate, a circuit structure layer, a light-emitting structure layer and at least one conductive structure. The circuit structure layer is located on the base substrate in the display area, and comprises a pixel circuit and an auxiliary power supply line. The light-emitting structure layer is located on a side of the circuit structure layer away from the base substrate. The light-emitting structure layer comprises a plurality of light-emitting elements. At least one light-emitting element comprises a stacked first electrode, an organic light-emitting layer and a second electrode. The first electrode is electrically connected to the pixel circuit, and the second electrode is located on a side of the first electrode away from the base substrate. The conductive structure is located on a side of the circuit structure layer away from the base substrate. The conductive structure is located in the interval between the respective light-emitting portions of at least two adjacent light-emitting elements. The second electrode of the light-emitting element is electrically connected to the auxiliary power supply line through the conductive structure.

Description

Technical Field

[0001] This article relates to but is not limited to the field of display technology, and in particular to a display substrate and a preparation method thereof, and a display device. Background Art

[0002] Organic Light Emitting Diode (OLED) and Quantum-dot Light Emitting Diode (QLED) are active light-emitting display devices with the advantages of self-luminescence, wide viewing angle, high contrast, low power consumption, extremely high response speed, light weight, flexibility and low cost. Summary of the invention

[0003] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0004] Embodiments of the present disclosure provide a display substrate and a method for manufacturing the same, and a display device.

[0005] On the one hand, an embodiment of the present disclosure provides a display substrate, comprising: a base substrate, a circuit structure layer, a light-emitting structure layer, and at least one conductive structure. The base substrate comprises a display area. The circuit structure layer is located on the base substrate of the display area, and the circuit structure layer comprises a pixel circuit and an auxiliary power supply line. The light-emitting structure layer is located on a side of the circuit structure layer away from the base substrate, and the light-emitting structure layer comprises a plurality of light-emitting elements, and at least one light-emitting element comprises: a stacked first electrode, an organic light-emitting layer, and a second electrode, the first electrode being electrically connected to the pixel circuit, and the second electrode being located on a side of the first electrode away from the base substrate. At least one conductive structure is located on a side of the circuit structure layer away from the base substrate, and the at least one conductive structure is located in a gap between the respective light-emitting portions of at least two adjacent light-emitting elements, and the second electrode of the light-emitting element is electrically connected to the auxiliary power supply line through the at least one conductive structure.

[0006] In some exemplary embodiments, the display substrate further comprises: a connection electrode disposed in the same layer as the first electrode of the light-emitting element, and the at least one conductive structure is electrically connected to the auxiliary power supply line via the connection electrode.

[0007] In some exemplary embodiments, the display substrate further comprises: a pixel definition layer located on a side of the circuit structure layer away from the base substrate. The pixel definition layer is provided with a first opening and a second opening, a portion of the light emitting element located in the second opening is used to emit light, and the at least one conductive structure is located in the first opening.

[0008] In some exemplary embodiments, the at least one conductive structure is located on a side of the pixel definition layer away from the substrate, or the at least one conductive structure is located on a side of the first electrode away from the substrate.

[0009] In some exemplary embodiments, the organic light-emitting layer is located on a side of the at least one conductive structure away from the base substrate, and the organic light-emitting layer exposes at least a portion of the at least one conductive structure away from the base substrate, and the conductive structure exposed by the organic light-emitting layer is in direct contact with the second electrode.

[0010] In some exemplary embodiments, in a direction perpendicular to the display substrate, a cross-section of the conductive structure is trapezoidal.

[0011] In some exemplary embodiments, a surface of the conductive structure on a side away from the substrate is parallel to a plane where the substrate is located, or protrudes toward a side away from the substrate.

[0012] In some exemplary embodiments, a surface of the conductive structure away from the substrate has at least one protrusion.

[0013] On the other hand, an embodiment of the present disclosure provides a display device, comprising the display substrate as described above.

[0014] On the other hand, the embodiment of the present disclosure provides a method for preparing a display substrate, comprising: forming a circuit structure layer on a base substrate of a display area, the circuit structure layer comprising: a pixel circuit and an auxiliary power supply line; forming at least one conductive structure and a light-emitting structure layer on the side of the circuit structure layer away from the base substrate. The light-emitting structure layer comprises a plurality of light-emitting elements, at least one light-emitting element comprising: a stacked first electrode, an organic light-emitting layer and a second electrode, the first electrode being electrically connected to the pixel circuit, and the second electrode being located on the side of the first electrode away from the base substrate; the conductive structure being located between the respective light-emitting portions of at least two adjacent light-emitting elements, and the second electrode of the light-emitting element being electrically connected to the auxiliary power supply line through the conductive structure.

[0015] In some exemplary embodiments, at least one conductive structure and a light-emitting structure layer are formed on a side of the circuit structure layer away from the base substrate, including: forming a first electrode of a light-emitting element, a pixel definition layer, and a conductive structure on a side of the circuit structure layer away from the base substrate; evaporating an organic material, wherein the organic material covers the first electrode and the conductive structure; using an organic solvent to dissolve the organic material covering the conductive structure to form an organic light-emitting layer, wherein the organic light-emitting layer exposes at least a portion of the conductive structure away from the base substrate; and forming a second electrode, wherein the second electrode is in direct contact with the conductive structure exposed by the organic light-emitting layer.

[0016] In some exemplary embodiments, at least a portion of the conductive structure exposed by the organic light emitting layer away from the base substrate includes: a top surface and at least a portion of a side surface of the conductive structure away from the base substrate.

[0017] In some exemplary embodiments, the first electrode of the light-emitting element, the pixel definition layer, and the conductive structure are formed on the side of the circuit structure layer away from the base substrate, including: forming the first electrode and the conductive structure of the light-emitting element in sequence on the side of the circuit structure layer away from the base substrate; forming a pixel definition layer, the pixel definition layer having a first opening and a second opening, the part of the light-emitting element located in the second opening is used for emitting light, and the conductive structure is located in the first opening.

[0018] In some exemplary embodiments, the first electrode of the light-emitting element, the pixel definition layer, and the conductive structure are formed on the side of the circuit structure layer away from the base substrate, including: forming the first electrode of the light-emitting element on the side of the circuit structure layer away from the base substrate; forming a pixel definition layer, the pixel definition layer having a first opening and a second opening, and the portion of the light-emitting element located at the second opening is used for emitting light; and forming a conductive structure in the first opening of the pixel definition layer.

[0019] Other aspects will be apparent upon reading and understanding the drawings and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the technical solution of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solution of the present disclosure and do not constitute a limitation on the technical solution of the present disclosure. The shape and size of one or more components in the accompanying drawings do not reflect the actual proportions and are only intended to illustrate the contents of the present disclosure.

[0021] Figure 1 is a schematic diagram of a display substrate according to at least one embodiment of the present disclosure;

[0022] Figure 2A partial schematic diagram of a display area of ​​a display substrate according to at least one embodiment of the present disclosure;

[0023] Figure 3 for Figure 2 Schematic diagram of a local cross section along the P-P' direction;

[0024] Figure 4 A schematic diagram of the preparation process of a display substrate according to at least one embodiment of the present disclosure;

[0025] Figure 5 It is another schematic diagram of the preparation process of the display substrate of at least one embodiment of the present disclosure;

[0026] Figure 6 for Figure 2 Another partial cross-sectional schematic diagram along the P-P' direction;

[0027] Fig. 7A and Figure 7B is another cross-sectional schematic diagram of a conductive structure of at least one embodiment of the present disclosure;

[0028] Figure 8 is a schematic diagram of a display device according to at least one embodiment of the present disclosure. DETAILED DESCRIPTION

[0029] The embodiments of the present disclosure will be described in detail below in conjunction with the accompanying drawings. The embodiments can be implemented in a plurality of different forms. A person skilled in the art can easily understand the fact that the method and content can be transformed into other forms without departing from the purpose and scope of the present disclosure. Therefore, the present disclosure should not be interpreted as being limited to the contents described in the following embodiments. In the absence of conflict, the embodiments in the present disclosure and the features in the embodiments can be arbitrarily combined with each other.

[0030] In the drawings, the size of one or more components, the thickness of a layer, or an area is sometimes exaggerated for the sake of clarity. Therefore, one embodiment of the present disclosure is not necessarily limited to the size, and the shape and size of one or more components in the drawings do not reflect the true proportion. In addition, the drawings schematically show ideal examples, and one embodiment of the present disclosure is not limited to the shapes or values ​​shown in the drawings.

[0031] The ordinal numbers such as "first", "second", and "third" in this specification are provided to avoid confusion of constituent elements, and are not intended to limit the quantity. The "plurality" in this disclosure means two or more.

[0032] In this specification, for the sake of convenience, the words and phrases indicating the orientation or positional relationship such as "middle", "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like are used to illustrate the positional relationship of the constituent elements with reference to the drawings. This is only for the convenience of describing this specification and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation of the present disclosure. The positional relationship of the constituent elements is appropriately changed according to the orientation of the constituent elements being described. Therefore, it is not limited to the words and phrases described in the specification, and can be appropriately replaced according to the circumstances.

[0033] In this specification, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, or a detachable connection, or an integral connection; it can be a mechanical connection, or a connection; it can be a direct connection, or an indirect connection through an intermediate, or the internal communication of two elements. For ordinary technicians in this field, the meanings of the above terms in this disclosure can be understood according to the circumstances.

[0034] In this specification, "electrical connection" includes the case where components are connected together through an element having some electrical function. There is no particular limitation on the "element having some electrical function" as long as it can transmit electrical signals between connected components. Examples of "element having some electrical function" include not only electrodes and wiring, but also switching elements such as transistors, resistors, inductors, capacitors, and other elements having multiple functions.

[0035] In this specification, a transistor refers to an element including at least three terminals: a gate, a drain, and a source. A transistor has a channel region between a drain (drain electrode terminal, a drain region, or a drain electrode) and a source (source electrode terminal, a source region, or a source electrode), and current can flow through the drain, the channel region, and the source. In this specification, a channel region refers to a region where current mainly flows.

[0036] In this specification, the first electrode may be a drain electrode and the second electrode may be a source electrode, or the first electrode may be a source electrode and the second electrode may be a drain electrode. In the case of using transistors with opposite polarities or when the current direction changes during circuit operation, the functions of the "source electrode" and the "drain electrode" are sometimes interchanged. Therefore, in this specification, the "source electrode" and the "drain electrode" may be interchanged. In addition, the gate electrode may also be called a control electrode.

[0037] In this specification, "parallel" means a state where the angle formed by two straight lines is greater than -10° and less than 10°, and therefore, also includes a state where the angle is greater than -5° and less than 5°. In addition, "perpendicular" means a state where the angle formed by two straight lines is greater than 80° and less than 100°, and therefore, also includes a state where the angle is greater than 85° and less than 95°.

[0038] The "light transmittance" in the present disclosure refers to the ability of light to pass through a medium, which is the percentage of the light flux passing through a transparent or translucent body to its incident light flux.

[0039] In the present disclosure, "about" and "substantially" mean that the limits are not strictly defined and the situation within the range of process and measurement errors is allowed. In the present disclosure, "substantially the same" means that the numerical values ​​differ by less than 10%.

[0040] The OLED light-emitting element includes: an anode (Anode), an organic light-emitting layer and a cathode (Cathode) stacked in sequence. For large-sized OLED display substrates, an open mask (Open Mask) is used to evaporate organic materials to prepare the organic light-emitting layer of the light-emitting element. The organic material will cover the entire display area, resulting in the inability of the auxiliary power supply wiring of the circuit structure layer to contact the cathode of the light-emitting element, and the effect of reducing the voltage drop cannot be achieved. In response to the above problems, in some implementations, after the organic light-emitting layer is evaporated, a laser is used to burn part of the organic light-emitting layer to achieve the overlap of the auxiliary power supply wiring and the cathode. However, the cost of this implementation method is relatively high, and there are high process requirements for removing the sintered organic light-emitting layer, which is prone to material residue and thus causes poor display. In addition, if the above-mentioned laser sintering is performed in the transparent display area of ​​the display substrate, the area of ​​the transparent display area will be occupied, thereby affecting the light transmittance of the display substrate.

[0041] The embodiment of the present disclosure provides a display substrate, comprising: a base substrate, a circuit structure layer, a light-emitting structure layer and at least one conductive structure. The circuit structure layer is located on the base substrate of the display area, and the circuit structure layer includes a pixel circuit and an auxiliary power supply line. The light-emitting structure layer is located on the side of the circuit structure layer away from the base substrate. The light-emitting structure layer includes a plurality of light-emitting elements, and at least one light-emitting element includes: a stacked first electrode, an organic light-emitting layer and a second electrode. The first electrode is electrically connected to the pixel circuit, and the second electrode is located on the side of the first electrode away from the base substrate. At least one conductive structure is located on the side of the circuit structure layer away from the base substrate, and at least one conductive structure is located in the interval between the respective light-emitting parts of at least two adjacent light-emitting elements. The second electrode of the light-emitting element is electrically connected to the auxiliary power supply line through at least one conductive structure.

[0042] The display substrate provided in this embodiment realizes electrical connection between the auxiliary power supply line and the second electrode of the light-emitting element by setting a conductive structure, and setting the conductive structure to be electrically connected to the auxiliary power supply line and the second electrode of the light-emitting element, thereby reducing voltage drop and power consumption and improving the display effect of the display substrate.

[0043] In some exemplary embodiments, the display substrate of this embodiment may be a large-sized OLED display substrate of a top emission structure. For example, the resolution of the display substrate may be 3840×2160 or 7680×4320. However, this embodiment is not limited thereto.

[0044] In some exemplary embodiments, the display substrate may further include: a connection electrode disposed in the same layer as the first electrode of the light-emitting element. At least one conductive structure is electrically connected to the auxiliary power supply line through the connection electrode. For example, the conductive structure and the connection electrode may be in a one-to-one or many-to-one relationship. However, this embodiment is not limited to this. For example, the conductive structure may be directly electrically connected to the auxiliary power supply line.

[0045] In some exemplary embodiments, the display substrate may further include: a pixel definition layer. The pixel definition layer is located on a side of the circuit structure layer away from the base substrate. The pixel definition layer is provided with a first opening and a second opening, and a portion of the light-emitting element located in the second opening is used to emit light, and at least one conductive structure is located in the first opening. In some examples, one conductive structure may be provided in one first opening, or multiple conductive structures may be provided. However, this embodiment is not limited to this.

[0046] In some exemplary embodiments, at least one conductive structure is located on a side of the pixel definition layer away from the substrate, or at least one conductive structure is located on a side of the first electrode away from the substrate. However, this embodiment is not limited to this.

[0047] In some exemplary embodiments, the organic light-emitting layer is located on a side of at least one conductive structure away from the base substrate, and the organic light-emitting layer exposes at least a portion of the at least one conductive structure away from the base substrate, and the conductive structure exposed by the organic light-emitting layer is in direct contact with the second electrode. In this exemplary embodiment, the second electrode of the light-emitting element is in surface-to-surface contact with the conductive structure exposed by the organic light-emitting layer, which is conducive to ensuring the electrical connection effect between the second electrode and the conductive structure.

[0048] In some exemplary embodiments, the cross-section of the conductive structure is a trapezoid in a direction perpendicular to the display substrate. In some examples, the surface of the conductive structure away from the base substrate is parallel to the plane where the base substrate is located, or protrudes toward the side away from the base substrate. However, this embodiment is not limited to this.

[0049] The display substrate of this embodiment is described below by means of some examples.

[0050] Figure 1 is a schematic diagram of a display substrate according to at least one embodiment of the present disclosure. Figure 2 FIG. 1 is a partial schematic diagram of a display area of ​​a display substrate according to at least one embodiment of the present disclosure. In some exemplary embodiments, Figure 1 As shown, the display substrate of this embodiment may include: a display area A and a non-display area B located around the display area A. The non-display area B includes a peripheral area located outside the display area and a binding area located on one side of the display area. The display area A is provided with at least a plurality of sub-pixels PX. At least one sub-pixel PX among the plurality of sub-pixels includes: a light-emitting element and a pixel circuit that drives the light-emitting element to emit light. For example, the pixel circuit is configured to provide a driving current to drive the light-emitting element to emit light. The pixel circuit may include a plurality of transistors and at least one capacitor, for example, the pixel circuit may be a 3T1C (3 transistors and 1 capacitor) structure, a 7T1C (7 transistors and 1 capacitor) structure, or a 5T1C (5 transistors and 1 capacitor) structure, etc. In some examples, the light-emitting element may be an organic light-emitting diode (OLED), and the light-emitting element emits red light, green light, blue light, or white light, etc. when driven by its corresponding pixel circuit. The color of the light emitted by the light-emitting element may be determined according to needs. In some examples, the light-emitting element may include: an anode, a cathode, and an organic light-emitting layer located between the anode and the cathode. The anode of the light-emitting element may be electrically connected to the corresponding pixel circuit. However, this embodiment is not limited to this.

[0051] In some exemplary embodiments, a pixel unit of the display area may include three sub-pixels, and the three sub-pixels may be red sub-pixels, green sub-pixels, and blue sub-pixels, respectively. However, this embodiment is not limited to this. In some examples, a pixel unit may include four sub-pixels, and the four sub-pixels may be red sub-pixels, green sub-pixels, blue sub-pixels, and white sub-pixels, respectively.

[0052] In some exemplary embodiments, the shape of the light-emitting element may be a rectangle, a rhombus, a pentagon, or a hexagon. When a pixel unit includes three sub-pixels, the light-emitting elements of the three sub-pixels may be arranged in parallel horizontally, vertically, or in a triangle; when a pixel unit includes four sub-pixels, the light-emitting elements of the four sub-pixels may be arranged in parallel horizontally, vertically, or in a square. However, this embodiment is not limited to this.

[0053] In some exemplary embodiments, Figure 2As shown, in a plane parallel to the display substrate, the display area A is also provided with a plurality of conductive structures 30. The conductive structure 30 may be located in the interval between the respective light-emitting portions of at least two adjacent light-emitting elements. The portion of the light-emitting element located in the first opening of the pixel definition layer is used for emitting light. The portion of the light-emitting element used for emitting light may be referred to as the light-emitting region of the light-emitting element, and the region outside the light-emitting region of the light-emitting element is the non-light-emitting region. The conductive structure 30 is located in the non-light-emitting region to avoid affecting the light-emitting element.

[0054] In some exemplary embodiments, Figure 2 As shown, the conductive structure 30 and the pixel unit can correspond one to one, that is, one conductive structure 30 can be located in the non-luminous area of ​​one pixel unit. However, this embodiment is not limited to this. For example, the conductive structure and the sub-pixel can be in a one-to-one or one-to-many relationship. For example, a conductive structure can be set in the non-luminous area of ​​a sub-pixel, or a conductive structure can be set in the non-luminous area between two adjacent sub-pixels.

[0055] Figure 3 for Figure 2 A schematic diagram of a partial cross section along the P-P' direction in FIG. In some exemplary embodiments, as Figure 3 As shown, in a direction perpendicular to the display substrate, the display area includes: a base substrate 100, a circuit structure layer disposed on the base substrate 100, a light emitting structure layer located on a side of the circuit structure layer away from the base substrate 100, and a conductive structure 30. The circuit structure layer may include a pixel circuit and an auxiliary power supply line 31. The light emitting structure layer may include a plurality of light emitting elements. At least one light emitting element may include: a stacked first electrode 211, an organic light emitting layer 212, and a second electrode 213. The first electrode 211 is electrically connected to the pixel circuit, and the second electrode 213 is located on a side of the first electrode 211 away from the base substrate 100. In this example, the first electrode 211 may be an anode, and the second electrode 213 may be a cathode.

[0056] In some exemplary embodiments, Figure 3 As shown, in a direction perpendicular to the display substrate, the circuit structure layer may include: a semiconductor layer, a first conductive layer, a second conductive layer, and a third conductive layer sequentially arranged on the base substrate 100. A first insulating layer 101 is arranged between the semiconductor layer and the first conductive layer, a second insulating layer 102 is arranged between the first conductive layer and the second conductive layer, and a third insulating layer 103 is arranged between the second conductive layer and the third conductive layer. A fourth insulating layer 104 and a fifth insulating layer 105 are arranged on the side of the third conductive layer away from the base substrate 100. In some examples, the first insulating layer 101 to the fourth insulating layer 104 may be inorganic insulating layers, and the fifth insulating layer 105 may be an organic insulating layer. However, this embodiment is not limited to this.

[0057] Figure 4 FIG. 1 is a schematic diagram of the preparation process of a display substrate according to at least one embodiment of the present disclosure. Figure 3 and Figure 4 The structure of the display substrate of this embodiment is exemplified by the preparation process of the display substrate. The "patterning process" mentioned in the present disclosure includes processes such as coating photoresist, mask exposure, development, etching, and stripping photoresist for metal materials, inorganic materials or transparent conductive materials, and includes processes such as coating organic materials, mask exposure and development for organic materials. Deposition can be any one or more of sputtering, evaporation, and chemical vapor deposition, coating can be any one or more of spraying, spin coating and inkjet printing, and etching can be any one or more of dry etching and wet etching, which are not limited in the present disclosure. "Thin film" refers to a layer of thin film made by deposition, coating or other processes on a substrate of a certain material. If the "thin film" does not require a patterning process during the entire production process, the "thin film" can also be called a "layer". If the "thin film" requires a patterning process during the entire production process, it is called a "thin film" before the patterning process and a "layer" after the patterning process. The "layer" after the patterning process contains at least one "pattern".

[0058] The term "A1 and A2 are arranged in the same layer" in the present disclosure means that A1 and A2 are formed simultaneously by the same patterning process. "The same layer" does not always mean that the thickness of the layer or the height of the layer is the same in the cross-sectional view. "The projection of A1 includes the projection of A2" means that the projection of A2 falls within the projection range of A1, or the projection of A1 covers the projection of A2.

[0059] In some exemplary embodiments, the preparation process of the display substrate of this embodiment may include the following steps.

[0060] (1) Preparing a circuit structure layer on a substrate.

[0061] In some exemplary embodiments, the circuit structure layer may include a plurality of pixel circuits, each pixel circuit including a plurality of transistors and at least one storage capacitor, such as a 2T1C, 3T1C, or 7T1C design. Figure 3 and Figure 4 As shown, a sub-pixel is taken as an example for illustration, and the pixel circuit of the sub-pixel is only illustrated by taking a first transistor and a first storage capacitor as an example.

[0062] In some exemplary embodiments, the process of preparing the circuit structure layer includes the following steps.

[0063] A semiconductor film is deposited on the base substrate 100 and patterned by a patterning process to form a semiconductor layer. The semiconductor layer includes at least: a first active layer.

[0064] Subsequently, a first insulating film and a first conductive film are deposited in sequence, and the first conductive film is patterned by a patterning process to form a first insulating layer 101 covering the semiconductor layer and a first conductive layer disposed on the first insulating layer 101. The first conductive layer includes at least: a first gate electrode and a first capacitor electrode.

[0065] Subsequently, a second insulating film and a second conductive film are sequentially deposited, and the second conductive film is patterned by a patterning process to form a second insulating layer 102 covering the first conductive layer, and a second conductive layer disposed on the second insulating layer 102. The second conductive layer at least includes: a second capacitor electrode. The position of the second capacitor electrode corresponds to the position of the first capacitor electrode.

[0066] Subsequently, a third insulating film is deposited and patterned by a patterning process to form a third insulating layer 103 covering the second conductive layer. At least two first via holes are formed on the third insulating layer 103, and the third insulating layer 103, the second insulating layer 102 and the first insulating layer 101 in the first via holes are etched away to expose the surface of the first active layer.

[0067] Subsequently, a third conductive film is deposited, and the third conductive film is patterned by a patterning process to form a third conductive layer on the third insulating layer 103. The third conductive layer at least includes: a first source electrode and a first drain electrode, and an auxiliary power supply line 31. The first source electrode and the first drain electrode can be connected to the first active layer through a first via, respectively. The auxiliary power supply line 31 is configured to transmit a low level signal (VSS).

[0068] like Figure 3 As shown, the first active layer, the first gate electrode, the first source electrode and the first drain electrode may constitute a first transistor 201 , and the first capacitor electrode and the second capacitor electrode may constitute a first storage capacitor 202 .

[0069] In some exemplary embodiments, the base substrate 100 may be a rigid substrate, such as a glass substrate. However, this embodiment is not limited thereto. For example, the base substrate may be a flexible substrate.

[0070] In some exemplary embodiments, the first insulating layer 101, the second insulating layer 102 and the third insulating layer 103 may be made of any one or more of silicon oxide (SiOx), silicon nitride (SiNx) and silicon oxynitride (SiON), and may be a single layer, a multilayer or a composite layer. The first insulating layer 101 and the second insulating layer 102 may be referred to as a gate insulator (GI) layer; the third insulating layer 103 may be referred to as an interlayer dielectric (ILD) layer. The first metal film, the second metal film and the third metal film may be made of metal materials, such as any one or more of silver (Ag), copper (Cu), aluminum (Al), titanium (Ti) and molybdenum (Mo), or alloy materials of the above metals, such as aluminum neodymium alloy (AlNd) or molybdenum niobium alloy (MoNb), and may be a single layer structure, or a multilayer composite structure, such as Ti / Al / Ti, etc. The semiconductor film may be made of one or more materials such as amorphous indium gallium zinc oxide (a-IGZO), zinc oxynitride (ZnON), indium zinc tin oxide (IZTO), amorphous silicon (a-Si), polycrystalline silicon (p-Si), sexithiophene, polythiophene, etc., that is, the present disclosure is applicable to transistors manufactured based on oxide technology, silicon technology, and organic technology. However, this embodiment is not limited to this.

[0071] (2) Forming a fourth insulating layer and a fifth insulating layer on the base substrate on which the aforementioned pattern is formed.

[0072] In some exemplary embodiments, a fourth insulating film is deposited on the substrate 100 on which the aforementioned pattern is formed, and a fourth insulating layer 104 is formed by a patterning process. Subsequently, a first flat film is coated, and the first flat film is patterned by a patterning process to form a fifth insulating layer 105. The fifth insulating layer 105 is provided with a plurality of first transfer holes and a plurality of second transfer holes, and the fourth insulating layer 104 and the fifth insulating layer 105 in the first transfer holes and the second transfer holes are removed to expose the third conductive layer. For example, the first transfer hole exposes the surface of the auxiliary power supply wiring 31 of the third conductive layer, and the second transfer hole exposes the surface of the first drain electrode of the first transistor 201 of the pixel circuit.

[0073] In some exemplary embodiments, the fourth insulating layer 104 may be made of any one or more of silicon oxide (SiOx), silicon nitride (SiNx) and silicon oxynitride (SiON), and may be a single layer, a multilayer or a composite layer. The fifth insulating layer 105 may be made of an organic material such as polyimide, acrylic or polyethylene terephthalate. The fourth insulating layer 104 may be called a passivation layer, and the fifth insulating layer 105 may be called a planarization layer.

[0074] (3) On the base substrate on which the aforementioned pattern is formed, a first electrode and a connecting electrode are formed. In some examples, the first electrode 211 may be a reflective anode.

[0075] In some exemplary embodiments, a fourth conductive film is deposited on the base substrate 100 on which the aforementioned pattern is formed, and the fourth conductive film is patterned by a patterning process to form the first electrode 211 and the connecting electrode 32. For example, the connecting electrode 32 may be electrically connected to the auxiliary power supply trace 31 through a first transfer hole, and the first electrode 211 may be electrically connected to the first drain electrode of the first transistor 201 of the pixel circuit through a second transfer hole.

[0076] In some exemplary embodiments, the fourth conductive film may be made of a metal material, such as any one or more of magnesium (Mg), silver (Ag), copper (Cu), aluminum (Al), titanium (Ti) and molybdenum (Mo), or an alloy material of the above metals, such as aluminum-neodymium alloy (AlNd) or molybdenum-niobium alloy (MoNb). It may be a single-layer structure, or a multi-layer composite structure, such as Ti / Al / Ti, or a stack structure formed by a metal and a transparent conductive material, such as reflective materials such as ITO / Ag / ITO, Mo / AlNd / ITO, etc.

[0077] (4) Forming a pixel definition layer pattern on the base substrate having the aforementioned pattern.

[0078] In some exemplary embodiments, a pixel definition film is coated on the base substrate 100 on which the aforementioned pattern is formed, and the pixel definition film is patterned by a patterning process to form a pixel definition layer 214. The pixel definition layer 214 is provided with a first opening K1 and a second opening K2. The pixel definition layer 214 in the first opening K1 is removed to expose at least a portion of the surface of the connection electrode 32, and the pixel definition layer 214 in the second opening K2 is removed to expose at least a portion of the surface of the first electrode 211.

[0079] In some examples, the pixel definition layer 214 may be made of polyimide, acrylic, polyethylene terephthalate, or the like.

[0080] (5) Forming a conductive structure on the base substrate on which the aforementioned pattern is formed.

[0081] In some exemplary embodiments, a conductive structure 30 is formed on the substrate 100 on which the aforementioned pattern is formed. The conductive structure 30 may be located in the first opening K1 of the pixel definition layer 214 and electrically connected to the connection electrode 32. In some examples, the conductive structure 30 may be made of a metal material, such as any one or more of silver (Ag), copper (Cu), aluminum (Al), titanium (Ti) and molybdenum (Mo), or an alloy material of the above metals, such as aluminum-neodymium alloy (AlNd) or molybdenum-niobium alloy (MoNb), and may be a single-layer structure, or a multi-layer composite structure, such as Ti / Al / Ti, etc.

[0082] In some exemplary embodiments, a conductive structure 30 may be disposed in a first opening K1 formed by the pixel definition layer 214. However, this embodiment is not limited thereto. For example, a plurality of conductive structures may be disposed in a first opening. The plurality of conductive structures may be electrically connected to a connection electrode, or may be electrically connected to a plurality of connection electrodes, thereby achieving electrical connection with the auxiliary power supply line.

[0083] In some examples, in a direction perpendicular to the display substrate, the cross-section of the conductive structure 30 may be a trapezoid, and the surface of the conductive structure 30 away from the base substrate 100 may be parallel to the plane where the base substrate 100 is located. In other words, the top surface of the conductive structure 30 away from the base substrate 100 may be a flat surface. However, this embodiment is not limited to this.

[0084] In some examples, the orthographic projection of the conductive structure 30 on the base substrate 100 may be a rectangle or a circle. However, this embodiment is not limited to this.

[0085] (6) Forming an organic light-emitting layer on the base substrate having the aforementioned pattern.

[0086] In some exemplary embodiments, an organic material 215 is evaporated on the substrate 100 formed with the aforementioned pattern using an open mask; subsequently, an organic solvent is dripped into the first opening K1 to dissolve the organic material 215 covering the top of the conductive structure 30 away from the substrate 100 to form an organic light-emitting layer 212. The organic material 215 covering the top of the conductive structure 30 can be dissolved by the organic solvent, thereby flowing into the first opening K1, exposing the top and at least part of the side of the conductive structure 30 away from the substrate 100. In this example, the organic material can expose the top and at least part of the side of the conductive structure 30 after being fixed in the first opening K1. In some examples, the thickness of the organic light-emitting layer in the first opening K1 can be greater than the thickness of the organic light-emitting layer in the second opening K2, and the thickness of the organic light-emitting layer in the first opening K1 can be less than the thickness of the conductive structure 30. However, this embodiment is not limited to this. For example, the organic light-emitting layer can only expose the top surface of the conductive structure 30 away from the substrate 100.

[0087] In the present disclosure, the thickness is the vertical distance between the surface on the side away from the substrate and the surface on the side close to the substrate.

[0088] In this example, the organic light-emitting layer may include a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer. For example, at least one of the hole injection layer, the hole transport layer, and the electron transport layer may be a common layer of a plurality of sub-pixels. However, this embodiment is not limited to this.

[0089] In some examples, the volume of the organic solvent after solidification may be less than three quarters of the volume of the conductive structure in the first opening, for example, three fifths of the volume of the conductive structure. In this way, the organic material can be dissolved and the volume after dissolution can be prevented from being too large and covering the top surface of the conductive structure. However, this embodiment is not limited to this.

[0090] (7) On the base substrate having the above-mentioned pattern formed thereon, a second electrode of the light-emitting element is formed.

[0091] In some examples, the second electrode 213 may be a transparent cathode. The light emitting element may emit light from the side away from the base substrate 100 through the transparent cathode to achieve top emission. In some examples, the display substrate of this embodiment may emit white light, and color display may be achieved through the color filter substrate. However, this embodiment is not limited to this.

[0092] In some exemplary embodiments, on the base substrate 100 formed with the aforementioned pattern, the second electrode 213 of the light emitting element is deposited and formed. The second electrodes 213 of the plurality of light emitting elements may be an integrated structure.

[0093] In some exemplary embodiments, the second electrode 213 of the light-emitting element may be made of any one or more of magnesium (Mg), silver (Ag), aluminum (Al), or an alloy made of any one or more of the above metals, or a transparent conductive material, such as indium tin oxide (ITO), or a multilayer composite structure of a metal and a transparent conductive material. This embodiment does not limit the thickness of the second electrode 213 of the light-emitting element. For example, a thinner second electrode can improve the light transmittance of the display substrate, and the second electrode can be directly in contact with the conductive structure to achieve electrical connection with the auxiliary power supply line, which can reduce power consumption and improve the display effect.

[0094] In this example, although the organic light-emitting layer is evaporated on the entire surface of the display area, during the preparation process, an organic solvent can be used to dissolve the organic material covering the conductive structure to expose the top of the conductive structure so that the conductive structure can be in direct contact with the second electrode, thereby achieving electrical connection between the second electrode of the light-emitting element and the auxiliary power supply line. Since the top and at least part of the side of the conductive structure can be in contact with the second electrode, surface-to-surface overlap can be achieved, thereby improving the overlap effect. Moreover, since a plurality of conductive structures are provided in the display area, even if there is organic material residue on the top of a few conductive structures, the overall electrical connection effect between the second electrode of the display substrate and the auxiliary power supply line can still be ensured.

[0095] In some examples, an encapsulation layer may be formed on the side of the second electrode of the light-emitting element away from the base substrate. The encapsulation layer may adopt a three-layer stacked structure of inorganic / organic / inorganic, or a five-layer structure of inorganic / organic / inorganic / organic / inorganic. However, this embodiment is not limited to this.

[0096] The structure of the display substrate of the embodiment of the present disclosure and its preparation process are merely exemplary. In some exemplary embodiments, the corresponding structure may be changed and the patterning process may be increased or decreased according to actual needs. For example, the connecting electrode may not be provided, and the conductive structure may be directly electrically connected to the auxiliary power supply line through a via provided in the fifth insulating layer. However, this embodiment is not limited to this.

[0097] The preparation process of this exemplary embodiment can be realized by using currently mature preparation equipment, and can be well compatible with existing preparation processes. The process is simple to realize, easy to implement, high in production efficiency, low in production cost, and high in yield rate.

[0098] Figure 5 FIG. 1 is another schematic diagram of a preparation process of a display substrate according to at least one embodiment of the present disclosure. In some exemplary embodiments, Figure 5As shown, after forming the first electrode 32 and the connecting electrode 211, a conductive structure 30 may be formed first, and the conductive structure 30 is electrically connected to the connecting electrode 32. Subsequently, a pixel definition layer 214 is formed, and the pixel definition layer 214 is provided with a first opening K1 and a second opening K2. The second opening K2 exposes at least a portion of the surface of the first electrode 211, and the first opening K1 exposes at least a portion of the surface of the conductive structure 30 and the connecting electrode 32. In some examples, the orthographic projection of the first opening K1 on the base substrate 100 may cover the orthographic projection of the conductive structure 30 on the base substrate 100, so that the first opening K1 may have a space for accommodating the subsequently dissolved organic material.

[0099] The rest of the preparation process of the display substrate of this embodiment can refer to the description of the previous embodiment, so it will not be described again here.

[0100] Figure 6 for Figure 2 Another partial cross-sectional schematic diagram along the P-P' direction in FIG. In some exemplary embodiments, as Figure 6 As shown, the surface of the fifth insulating layer 105 below the connecting electrode 32 on the side away from the base substrate 100 bulges toward the side away from the base substrate 100, so that the surface of the connecting electrode 32 on the side away from the base substrate 100 bulges toward the side away from the base substrate 100. The surface 301 of the conductive structure 30 on the side away from the base substrate 100 bulges toward the side away from the base substrate 100. For example, the surface 301 of the conductive structure 30 on the side away from the base substrate 100 can be an arc surface. In this way, after the organic material covering the surface 301 of the conductive structure 30 on the side away from the base substrate 100 is dissolved by the organic solvent, it can flow along the arc surface of the conductive structure 30 into the first opening K1, thereby facilitating the dissolved organic material to flow into the first opening K1, and effectively improving the residual organic material on the top of the conductive structure 30.

[0101] The remaining structures of the display substrate of this embodiment can refer to the description of the aforementioned embodiment, and thus will not be described in detail here.

[0102] Fig. 7A and Figure 7B FIG. 1 is another cross-sectional schematic diagram of a conductive structure of a display substrate according to at least one embodiment of the present disclosure. In some exemplary embodiments, Fig. 7A As shown, the conductive structure may have a protrusion 302 on the surface 301 of the side away from the substrate. Figure 7B As shown, a surface 301 of the conductive structure away from the substrate may have two protrusions 302. However, this embodiment is not limited to this.

[0103] The structure of the display area in this exemplary embodiment is similar to the corresponding structure described in the above embodiments, so it is not repeated here. The structure (or method) shown in this embodiment can be appropriately combined with the structure (or method) shown in other embodiments.

[0104] The disclosed embodiment also provides a method for preparing a display substrate, comprising: forming a circuit structure layer on a base substrate in a display area, the circuit structure layer comprising: a pixel circuit and an auxiliary power supply line; forming at least one conductive structure and a light-emitting structure layer on a side of the circuit structure layer away from the base substrate. The light-emitting structure layer comprises a plurality of light-emitting elements, at least one light-emitting element comprising: a stacked first electrode, an organic light-emitting layer and a second electrode, the first electrode being electrically connected to the pixel circuit, and the second electrode being located on a side of the first electrode away from the base substrate. The conductive structure is located in the interval between the respective light-emitting portions of at least two adjacent light-emitting elements. The second electrode of the light-emitting element is electrically connected to the auxiliary power supply line through the conductive structure.

[0105] In some exemplary embodiments, at least one conductive structure and a light-emitting structure layer are formed on a side of the circuit structure layer away from the base substrate, including: forming a first electrode of a light-emitting element, a pixel definition layer, and a conductive structure on a side of the circuit structure layer away from the base substrate; evaporating an organic material, wherein the organic material covers the first electrode and the conductive structure; using an organic solvent to dissolve the organic material covering the conductive structure to form an organic light-emitting layer, wherein the organic light-emitting layer exposes at least a portion of the conductive structure away from the base substrate; and forming a second electrode, wherein the second electrode is in direct contact with the conductive structure exposed by the organic light-emitting layer.

[0106] In some exemplary embodiments, at least a portion of the conductive structure exposed by the organic light emitting layer away from the base substrate includes: a top surface and at least a portion of a side surface of the conductive structure away from the base substrate.

[0107] In some exemplary embodiments, a first electrode of a light-emitting element, a pixel definition layer, and a conductive structure are formed on a side of a circuit structure layer away from a base substrate, including: forming a first electrode and a conductive structure of a light-emitting element in sequence on a side of a circuit structure layer away from a base substrate; forming a pixel definition layer, wherein a first opening and a second opening are formed in the pixel definition layer, a portion of the light-emitting element located in the second opening is used for emitting light, and the conductive structure is located in the first opening.

[0108] In some exemplary embodiments, a first electrode of a light-emitting element, a pixel definition layer, and a conductive structure are formed on a side of a circuit structure layer away from a base substrate, including: forming a first electrode of a light-emitting element on a side of a circuit structure layer away from a base substrate; forming a pixel definition layer, wherein a first opening and a second opening are formed in the pixel definition layer, and a portion of the light-emitting element located in the second opening is used for emitting light; and forming a conductive structure in the first opening of the pixel definition layer.

[0109] The preparation process of the display substrate of this embodiment can refer to the description of the above-mentioned embodiment, so it will not be described again here.

[0110] Figure 8 FIG. 1 is a schematic diagram of a display device according to at least one embodiment of the present disclosure. Figure 8 As shown, this embodiment provides a display device 91, including: a display substrate 910. The display substrate 910 is the display substrate provided in the above embodiment. In some examples, the display substrate 910 can be an OLED display substrate. The display device 91 can be: an OLED display device, a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, a navigator, a car display, a watch, a bracelet, or any other product or component with a display function. However, this embodiment is not limited to this.

[0111] The drawings in this disclosure only relate to the structures involved in this disclosure, and other structures can refer to the general design. In the absence of conflict, the embodiments of this disclosure, that is, the features in the embodiments, can be combined with each other to obtain new embodiments.

[0112] Those skilled in the art should understand that the technical solutions of the present disclosure may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present disclosure, and all should be included in the scope of the claims of the present disclosure.

Claims

1. A display substrate, characterized in that: include: A substrate base, including a display area; A circuit structure layer, located on the base substrate of the display area, the circuit structure layer including a pixel circuit and an auxiliary power supply line; a light-emitting structure layer, located on a side of the circuit structure layer away from the base substrate, the light-emitting structure layer comprising a plurality of light-emitting elements, at least one of the light-emitting elements comprising: a stacked first electrode, an organic light-emitting layer and a second electrode, the first electrode being electrically connected to the pixel circuit, and the second electrode being located on a side of the first electrode away from the base substrate; At least one conductive structure is located on a side of the circuit structure layer away from the base substrate, the at least one conductive structure is located between the light-emitting portions of at least two adjacent light-emitting elements, and the second electrode of the light-emitting element is electrically connected to the auxiliary power supply line through the at least one conductive structure; The organic light-emitting layer is located on a side of the at least one conductive structure away from the base substrate, and the organic light-emitting layer exposes at least a portion of the at least one conductive structure away from the base substrate, and the top and at least a portion of the side surface of the conductive structure exposed by the organic light-emitting layer are in direct contact with the second electrode; The surface of the conductive structure away from the substrate protrudes toward the side away from the substrate, or the surface of the conductive structure away from the substrate has at least one protrusion.

2. The display substrate according to claim 1, characterized in that: The display substrate further comprises: a connection electrode disposed in the same layer as the first electrode of the light emitting element, and the at least one conductive structure is electrically connected to the auxiliary power supply line via the connection electrode.

3. The display substrate according to claim 1, characterized in that: The display substrate further comprises: a pixel definition layer, located on a side of the circuit structure layer away from the base substrate; The pixel definition layer is provided with a first opening and a second opening, the portion of the light emitting element located in the second opening is used for emitting light, and the at least one conductive structure is located in the first opening.

4. The display substrate according to claim 3, characterized in that: The at least one conductive structure is located on a side of the pixel definition layer away from the substrate, or the at least one conductive structure is located on a side of the first electrode away from the substrate.

5. The display substrate according to claim 1, characterized in that: In a direction perpendicular to the display substrate, the cross section of the conductive structure is trapezoidal.

6. A display device, characterized in that: The display substrate comprises the display substrate as claimed in any one of claims 1 to 5.

7. A method for preparing a display substrate, characterized in that: include: Forming a circuit structure layer on the base substrate of the display area, the circuit structure layer comprising: a pixel circuit and an auxiliary power supply wiring; At least one conductive structure and a light-emitting structure layer are formed on a side of the circuit structure layer away from the base substrate; The light-emitting structure layer includes a plurality of light-emitting elements, at least one of which includes: a stacked first electrode, an organic light-emitting layer, and a second electrode, the first electrode is electrically connected to the pixel circuit, and the second electrode is located on a side of the first electrode away from the substrate; the conductive structure is located between the light-emitting portions of at least two adjacent light-emitting elements, and the second electrode of the light-emitting element is electrically connected to the auxiliary power supply line through the conductive structure; Wherein, forming at least one conductive structure and a light-emitting structure layer on a side of the circuit structure layer away from the base substrate comprises: A first electrode of a light-emitting element, a pixel definition layer and a conductive structure are formed on the side of the circuit structure layer away from the base substrate; wherein a surface of the conductive structure away from the base substrate protrudes toward a side away from the base substrate, or a surface of the conductive structure away from the base substrate has at least one protrusion; Vapor depositing an organic material, wherein the organic material covers the first electrode and the conductive structure; Using an organic solvent to dissolve the organic material covering the conductive structure to form an organic light-emitting layer, wherein the organic light-emitting layer exposes at least a portion of the conductive structure away from the base substrate; A second electrode is formed, wherein the second electrode is in direct contact with the top surface and at least a portion of the side surface of the conductive structure exposed by the organic light-emitting layer.

8. The preparation method according to claim 7, characterized in that: The first electrode of the light-emitting element, the pixel definition layer and the conductive structure formed on the side of the circuit structure layer away from the base substrate include: Forming a first electrode and a conductive structure that sequentially form a light-emitting element on a side of the circuit structure layer away from the base substrate; A pixel definition layer is formed, wherein the pixel definition layer is provided with a first opening and a second opening, the portion of the light emitting element located in the second opening is used for emitting light, and the conductive structure is located in the first opening.

9. The preparation method according to claim 7, characterized in that: The first electrode of the light-emitting element, the pixel definition layer and the conductive structure formed on the side of the circuit structure layer away from the base substrate include: Forming a first electrode of a light-emitting element on a side of the circuit structure layer away from the base substrate; forming a pixel definition layer, wherein the pixel definition layer is provided with a first opening and a second opening, and a portion of the light emitting element located at the second opening is used for emitting light; A conductive structure is formed in the first opening of the pixel definition layer.

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