Display substrate and preparation method thereof, and display device

Abstract

A display substrate and a preparation method thereof, and a display device, the display substrate comprising: a base substrate and a plurality of sub-pixels located on one side of the base substrate, each of the sub-pixels comprising: a first electrode, a first light-emitting material layer, a charge generation layer, a second light-emitting material layer and a second electrode stacked in sequence in a direction away from the base substrate, the charge generation layer being short-circuited with one of the first electrode and the second electrode.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to, but are not limited to, the field of display technology, and specifically relate to a display substrate and a method for preparing the same, and a display device. Background Art

[0002] Active Matrix Organic Light Emitting Diode (AMOLED) panels have the characteristics of faster response speed, higher contrast and wider viewing angle compared to traditional liquid crystal panels. Traditional white light AMOLED panels are realized by WOLED (White Organic Light-Emitting Diode) devices plus color filters (CF) of three colors of RGB. The light-emitting unit of the white light organic light-emitting diode is composed of sub-light-emitting units of different colors. Specifically, the sub-light-emitting units of different colors are stacked in series through a charge generation layer. However, in this panel structure, the transmittance of the color filters of the three colors of RGB is relatively low, and most of the energy of the white light emitted by the WOLED is absorbed by the color filters. In order to ensure the display brightness, the current passing through the WOLED needs to be increased, resulting in an increase in the power consumption of the display panel and a shortened life of the WOLED. Summary of the invention

[0003] The following is a summary of the subject matter of the detailed description of the present disclosure. This summary is not intended to limit the scope of the claims.

[0004] In a first aspect, an embodiment of the present disclosure provides a display substrate, comprising: a base substrate and a plurality of sub-pixels located on one side of the base substrate, each of the sub-pixels comprising: a first electrode, a first light-emitting material layer, a charge generation layer, a second light-emitting material layer and a second electrode stacked in sequence in a direction away from the base substrate, the charge generation layer being short-circuited with one of the first electrode and the second electrode.

[0005] In an exemplary embodiment, the sub-pixel further includes a shorting structure layer including a conductive material layer that short-circuits the charge generation layer and one of the first electrode and the second electrode.

[0006] In an exemplary embodiment, the short-circuiting structure layer further includes an insulating material layer, the conductive material layer short-circuits the charge generation layer and the first electrode, and the insulating material layer insulates the conductive material layer from the second light-emitting material layer and the second electrode, respectively.

[0007] In an exemplary embodiment, the short-circuiting structure layer further includes an insulating material layer, the conductive material layer short-circuits the charge generation layer and the second electrode, and the insulating material layer insulates the conductive material layer from the first light-emitting material layer and the first electrode, respectively.

[0008] In an exemplary embodiment, the short-circuit structure layer is located at a peripheral side of the first electrode, the first light emitting material layer, the charge generation layer, and the second light emitting material layer.

[0009] In an exemplary embodiment, a first opening is provided in the short-circuit structure layer, and the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer are located in the first opening, and the short-circuit structure layer covers the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer.

[0010] In an exemplary embodiment, each of the sub-pixels further includes: a pixel defining layer, a second opening being provided in the pixel defining layer, the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer being located in the second opening, a notch being provided on a side of the pixel defining layer, the short-circuit structure layer being provided on the same layer as the pixel defining layer, and the short-circuit structure layer being provided in the notch, and the short-circuit structure layer covering a portion of the circumferential side of the first electrode, a portion of the circumferential side of the first light-emitting material layer, a portion of the circumferential side of the charge generation layer and a portion of the circumferential side of the second light-emitting material layer.

[0011] In an exemplary embodiment, the conductive material layer is a metal or a conductive oxide.

[0012] In an exemplary embodiment, the insulating material layer is an inorganic insulating material or an organic insulating material.

[0013] In an exemplary embodiment, a first perforation is provided in the first light-emitting material layer, and the charge generation layer is connected to the first electrode through the first perforation; and / or a second perforation is provided in the second light-emitting material layer, and the charge generation layer is connected to the second electrode through the second perforation.

[0014] In an exemplary embodiment, the light emitted by the first luminescent material layer and the light emitted by the second luminescent material layer are mixed to form white light.

[0015] In an exemplary embodiment, the first light-emitting material layer includes a first sub-light-emitting material layer and a second sub-light-emitting material layer sequentially stacked in a direction away from the base substrate, and light emitted by the sub-light-emitting material layer and light emitted by the second sub-light-emitting material layer are mixed to produce yellow light.

[0016] In an exemplary embodiment, a color filter layer is further included, and the color filter layer is located on the side of the multiple sub-pixels away from the base substrate; the color filter layer includes multiple color resist blocks of different colors, and the orthographic projection of each of the sub-pixels on the base substrate is located within the orthographic projection of one of the color resist blocks on the base substrate.

[0017] In a second aspect, an embodiment of the present disclosure further provides a display device, comprising the aforementioned display substrate.

[0018] In a third aspect, the present disclosure also provides a method for preparing a display substrate, comprising:

[0019] A plurality of sub-pixels are formed on one side of the substrate, each of the sub-pixels comprising at least: a first electrode, a first light-emitting material layer, a charge generation layer, a second light-emitting material layer and a second electrode sequentially stacked in a direction away from the substrate;

[0020] The charge generation layer is short-circuited with one of the first electrode and the second electrode.

[0021] Other aspects will be apparent upon reading and understanding the drawings and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide an understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0023] Figure 1 Schematic diagram of the film structure of the light emitting device in a sub-pixel of the display substrate according to the embodiment of the present invention Figure 1 ;

[0024] Figure 2 Schematic diagram of the film structure of the light emitting device in a sub-pixel of the display substrate according to the embodiment of the present invention Figure 2 ;

[0025] Figure 3 A cross-sectional view of a pixel unit of a display substrate according to an embodiment of the present invention Figure 1 ;

[0026] Figure 4 It is an enlarged view of a light emitting device in a first sub-pixel of a display substrate according to an embodiment of the present invention;

[0027] Figure 5 It is an enlarged view of a light emitting device in a third sub-pixel of a display substrate according to an embodiment of the present invention;

[0028] Figure 6 The top view of each sub-pixel in the display substrate of the embodiment of the present invention is shown in FIG. Figure 1 ;

[0029] Figure 7 This is a schematic diagram showing a substrate after forming a first electrode and a third conductive material layer pattern according to an embodiment of the present invention;

[0030] Figure 8 This is a schematic diagram showing a substrate after an insulating material layer pattern is formed in an embodiment of the present invention;

[0031] Fig. 9 This is a schematic diagram showing a substrate after patterns of a first conductive material layer and a second conductive material layer are formed in an embodiment of the present invention;

[0032] Fig.10 This is a schematic diagram showing a substrate after forming a first light-emitting material layer, a charge generation layer, a second light-emitting material layer and a second electrode pattern according to an embodiment of the present invention;

[0033] Fig.11 A cross-sectional view of a pixel unit of a display substrate according to an embodiment of the present invention Figure 2 ;

[0034] Fig.12 A cross-sectional view of a pixel unit of a display substrate according to an embodiment of the present invention Figure 3 ;

[0035] Fig.13 The top view of each sub-pixel in the display substrate of the embodiment of the present invention is shown in FIG. Figure 2 . DETAILED DESCRIPTION

[0036] The embodiments of the present disclosure will be described in detail below in conjunction with the accompanying drawings. Note that the embodiments can be implemented in a plurality of different forms. A person of ordinary skill in the art can easily understand the fact that the methods and contents can be transformed into various 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.

[0037] 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", etc., 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 direction in which each constituent element is described. Therefore, it is not limited to the words and phrases described in the specification, and can be appropriately replaced according to the situation.

[0038] 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, a detachable connection, or an integral connection; it can be a mechanical connection, or an electrical 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.

[0039] The term "about" in the present disclosure refers to a numerical value that is not strictly limited to allow for process and measurement errors.

[0040] Compared with single-layer WOLED devices (>10cd / A), the efficiency of stacked WOLED devices will be significantly improved (>40cd / A), and the device voltage will also be significantly increased (4V→8V), resulting in a significant increase in the energy consumption of the device.

[0041] The WOLED display substrate in the related art includes a base substrate and a plurality of sub-pixels arranged on one side of the base substrate, each sub-pixel includes a first electrode, a first hole injection layer (HIL1), a first hole transport layer (ETL1), a first light-emitting material layer, a first electron transport layer (HTL1), a charge generation layer (CGL), a second hole injection layer (HIL2), a second hole transport layer (HTL2), a second light-emitting material layer, a second hole transport layer (ETL2), an electron injection layer (EIL), a polarizer, a second electrode and a capping layer, wherein the film layer between the first electrode and the second electrode constitutes a white light emitting layer.

[0042] In the related art, in a sub-pixel of a display substrate, when the first light-emitting material layer is lit, the first electrode transmits holes to a side of the first light-emitting material layer close to the first electrode, and the charge generation layer transmits electrons to a side of the first light-emitting material layer close to the second electrode, and the holes and electrons are combined in the first light-emitting material layer, so that the first light-emitting material layer emits yellow light; when the second light-emitting material layer is lit, the charge generation layer transmits holes to a side of the second light-emitting material layer close to the first electrode, and the second electrode transmits electrons to a side of the second light-emitting material layer close to the second electrode, and the holes and electrons are combined in the second light-emitting material layer, so that the second light-emitting material layer emits blue light; the yellow light emitted by the first light-emitting material layer and the blue light emitted by the second light-emitting material layer are mixed to form white light.

[0043] An embodiment of the present disclosure provides a display substrate, including: a base substrate and a plurality of sub-pixels located on one side of the base substrate, each of the sub-pixels including: a first electrode, a first light-emitting material layer, a charge generation layer, a second light-emitting material layer and a second electrode stacked in sequence in a direction away from the base substrate, the charge generation layer being short-circuited with one of the first electrode and the second electrode.

[0044] In an exemplary embodiment, the sub-pixel further includes a shorting structure layer including a conductive material layer that short-circuits the charge generation layer and one of the first electrode and the second electrode.

[0045] In an exemplary embodiment, the short-circuiting structure layer further includes an insulating material layer, the conductive material layer short-circuits the charge generation layer and the first electrode, and the insulating material layer insulates the conductive material layer from the second light-emitting material layer and the second electrode, respectively.

[0046] In an exemplary embodiment, the short-circuiting structure layer further includes an insulating material layer, the conductive material layer short-circuits the charge generation layer and the second electrode, and the insulating material layer insulates the conductive material layer from the first light-emitting material layer and the first electrode, respectively.

[0047] In an exemplary embodiment, the short-circuit structure layer is located at a peripheral side of the first electrode, the first light emitting material layer, the charge generation layer, and the second light emitting material layer.

[0048] In an exemplary embodiment, a first opening is provided in the short-circuit structure layer, and the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer are located in the first opening, and the short-circuit structure layer covers the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer.

[0049] In an exemplary embodiment, each of the sub-pixels further includes: a pixel defining layer, a second opening being provided in the pixel defining layer, the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer being located in the second opening, a notch being provided on a side of the pixel defining layer, the short-circuit structure layer being provided on the same layer as the pixel defining layer, and the short-circuit structure layer being provided in the notch, and the short-circuit structure layer covering a portion of the circumferential side of the first electrode, a portion of the circumferential side of the first light-emitting material layer, a portion of the circumferential side of the charge generation layer and a portion of the circumferential side of the second light-emitting material layer.

[0050] In an exemplary embodiment, the conductive material layer is a metal or a conductive oxide.

[0051] In an exemplary embodiment, the insulating material layer is an inorganic insulating material or an organic insulating material.

[0052] In an exemplary embodiment, a first perforation is provided in the first light-emitting material layer, and the charge generation layer is connected to the first electrode through the first perforation; and / or a second perforation is provided in the second light-emitting material layer, and the charge generation layer is connected to the second electrode through the second perforation.

[0053] In an exemplary embodiment, the light emitted by the first luminescent material layer and the light emitted by the second luminescent material layer are mixed to form white light.

[0054] In an exemplary embodiment, the first light-emitting material layer includes a first sub-light-emitting material layer and a second sub-light-emitting material layer sequentially stacked in a direction away from the base substrate, and light emitted by the sub-light-emitting material layer and light emitted by the second sub-light-emitting material layer are mixed to produce yellow light.

[0055] In an exemplary embodiment, a color filter layer is further included, and the color filter layer is located on the side of the multiple sub-pixels away from the base substrate; the color filter layer includes multiple color resist blocks of different colors, and the orthographic projection of each of the sub-pixels on the base substrate is located within the orthographic projection of one of the color resist blocks on the base substrate.

[0056] In a sub-pixel of the display substrate of the embodiment of the present invention, a part of the light-emitting material layer in the sub-pixel emits light by short-circuiting the charge generation layer with one of the first electrode and the second electrode, thereby reducing the power consumption of the display substrate of the embodiment of the present invention.

[0057] The display substrate of the embodiment of the present invention may include a plurality of pixel areas, and the plurality of pixel areas may be arranged in a matrix manner. In an exemplary embodiment, the pixel area may include at least one pixel unit, the pixel unit may include at least one sub-pixel, and the sub-pixel may include a stacked substrate, a pixel driving circuit, a light-emitting device, and a color filter layer. The pixel driving circuit is configured to output a light-emitting signal to the light-emitting device. The light-emitting device is configured to emit light of corresponding brightness under the drive of the pixel driving circuit. Among them, the pixel driving circuit mainly includes a plurality of thin film transistors (Thin Film Transistor, TFT). The pixel driving circuit may be a 3T1C, 4T1C, 5T1C, 5T2C, 6T1C, 7T1C or 8T2C structure.

[0058] In an exemplary embodiment, the shape of the sub-pixel in the pixel unit may be a rectangle, a rhombus, a pentagon, or a hexagon. When the pixel unit includes three sub-pixels, the light-emitting devices in the three sub-pixels may be arranged in parallel horizontally, in parallel vertically, or in a triangle pattern. When the pixel unit includes four sub-pixels, the light-emitting devices in the four sub-pixels may be arranged in parallel horizontally, in parallel vertically, or in a square pattern, which is not limited in the present disclosure.

[0059] Figure 1 Schematic diagram of the film structure of the light emitting device in a sub-pixel of the display substrate according to the embodiment of the present invention Figure 1 .like Figure 1 As shown, the light-emitting device in a sub-pixel of the display substrate of the embodiment of the present invention includes: a first electrode 1, a first hole injection layer 2 (HIL1), a first hole transport layer 3 (HTL2), a first light-emitting material layer 4, a first electron transport layer 5 (ETL1), a charge generation layer 6 (CGL), a second hole injection layer 7 (HIL2), a second hole transport layer 8 (HTL2), a second light-emitting material layer 9, a second electron transport layer 10 (ETL2), an electron injection layer 11 (EIL), a second electrode 12, a polarizer 13 and a capping layer 14, which are stacked in sequence in a direction away from the base substrate. Among them, the charge generation layer (CGL) serves as an intermediate electrode. The film layer between the first electrode 1 and the second electrode 12 constitutes a white light emitting layer. Of course, the structure of the white light emitting layer in the embodiment of the present invention is not limited to this, and can also be other structures.

[0060] In an exemplary embodiment, the first electrode 1 may be an anode, and the second electrode 12 may be a cathode. The type and material of the first electrode 1 are not limited. For example, the first electrode 1 may be formed of a transparent conductive material having a high work function, and the material of the first electrode 1 may include indium tin oxide (ITO), indium zinc oxide (IZO), indium gallium oxide (IGO), gallium zinc oxide (GZO), zinc oxide (ZnO), indium oxide (In2O3), aluminum zinc oxide (AZO) and carbon nanotubes. The type and material of the second electrode 12 are not limited. For example, the second electrode 12 may be formed of a material with high conductivity and low work function, and the material of the second electrode 12 may include alloys such as magnesium aluminum alloy (MgAl), magnesium aluminum alloy (MgAg), lithium aluminum alloy (LiAl) or single metals such as magnesium, aluminum, lithium, and silver.

[0061] In a sub-pixel of the display substrate of the embodiment of the present invention, the charge generation layer 6 is short-circuited with one of the first electrode 1 and the second electrode 12, so that part of the light-emitting material layer in the sub-pixel emits light, thereby reducing the power consumption of the display substrate of the embodiment of the present invention.

[0062] In an exemplary embodiment, Figure 1As shown, in a sub-pixel, the charge generation layer 6 is short-circuited with the first electrode 1. When the sub-pixel is lit, the holes emitted by the first electrode 1 do not pass through the first sub-light-emitting material layer 4 between the charge generation layer 6 and the first electrode 1, but are directly input into the charge generation layer 6, so that the first electrode 1 transmits holes to the side of the second sub-light-emitting material layer 9 close to the first electrode 1 through the charge generation layer 6; the second electrode 12 transmits electrons toward the side of the second sub-light-emitting material layer 9 close to the second electrode 12, so that the second sub-light-emitting material layer 9 emits light. Since the first sub-light-emitting material layer 4 has no transmitted holes, the first sub-light-emitting material layer 4 does not emit light, thereby reducing the luminescence power consumption of the sub-pixel, and further reducing the luminescence power consumption of the display substrate of the embodiment of the present invention.

[0063] Figure 2 Schematic diagram of the film structure of the light emitting device in a sub-pixel of the display substrate according to the embodiment of the present invention Figure 2 .like Figure 2 As shown, in a sub-pixel, the charge generation layer 6 is short-circuited with the second electrode 12. When the sub-pixel is lit, the electrons emitted by the second electrode 12 do not pass through the second sub-light-emitting material layer 9 between the charge generation layer 6 and the second electrode 12, but are directly input into the charge generation layer 6, so that the second electrode 12 transmits electrons to the side of the first sub-light-emitting material layer 4 close to the second electrode 12 through the charge generation layer 6; the first electrode 1 transmits holes toward the side of the first sub-light-emitting material layer 4 close to the first electrode 1, so that the first sub-light-emitting material layer 4 emits light, and since the second sub-light-emitting material layer 9 is not transmitted electrons, the second sub-light-emitting material layer 9 does not emit light, thereby reducing the luminescence power consumption of the sub-pixel, and further reducing the luminescence power consumption of the display substrate of the embodiment of the present invention.

[0064] In an exemplary embodiment, the first hole transport layer 3 and the second hole transport layer 8 may play a role in promoting the transport of holes. The materials of the first hole transport layer 3 and the second hole transport layer 8 may include any one selected from the following: for example, NPD (N, N-dinaphthyl-N, N'-diphenylbenzidine) (N, N'-bis (naphthalene-1-yl) -N, N'-bis (phenyl) -2,2'-dimethylbenzidine), TPD (N, N'-bis- (3-methylphenyl) -N, N'-bis- (phenyl) - benzidine), and MTDATA (4, 4', 4-tris (N-3-methylphenyl-N-phenyl-amino) -triphenylamine). However, the present embodiment is not limited thereto.

[0065] In an exemplary embodiment, the first hole injection layer 2 and the second hole injection layer 7 may facilitate the injection of holes. The first hole injection layer 2 and the second hole injection layer 7 may be made of at least one selected from the following: for example, CuPc (copper phthalocyanine), PEDOT (poly (3,4) -ethylenedioxythiophene), PANI (polyaniline), NPD (N, N-dinaphthyl-N, N'-diphenylbenzidine) and a combination thereof. However, the present embodiment is not limited thereto.

[0066] In an exemplary embodiment, the first electron transport layer 5 and the second electron transport layer 10 receive electrons and may transfer the supplied electrons to the light emitting layer. The first electron transport layer 1514 and the second electron transport layer 1524 also serve to facilitate the transport of electrons. The first electron transport layer 5 and the second electron transport layer 10 materials may include at least one selected from the following: for example, Alq3 (tris (8-hydroxyquinoline) aluminum), Liq (8-hydroxyquinoline lithium), PBD (2- (4-biphenyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole), TAZ (3- (4-biphenyl) -4-phenyl-5-tert-butylphenyl -1,2,4-triazole), spiro-PBD, BAlq (bis (2-methyl-8-quinoline) -4- (phenylphenol) aluminum), SAlq, TPBi (2,2',2- (1,3,5-benzinetriyl) -tris (1-phenyl-1-H-benzimidazole))), oxadiazole, triazole, phenanthroline, benzoxazole and benzothiazole. However, the present embodiment is not limited thereto.

[0067] Figure 3 A cross-sectional view of a pixel unit of a display substrate according to an embodiment of the present invention Figure 1 .like Figure 3 As shown, a pixel unit of a display substrate according to an embodiment of the present invention may include a first sub-pixel P1 emitting a first color light, a second sub-pixel P2 emitting a second color light, and a third sub-pixel P3 emitting a third color light, and each sub-pixel may include a pixel driving circuit 200, a light-emitting device 300, and a color filter layer 400 sequentially stacked in a direction away from the base substrate 100. The pixel driving circuit 200 is configured to output a light-emitting signal to the light-emitting device 300. The light-emitting devices 300 in the first sub-pixel P1, the second sub-pixel P2, and the third sub-pixel P3 are respectively connected to the pixel driving circuit 200 of the sub-pixel, and the light-emitting device 300 is configured to emit light of corresponding brightness under the drive of the pixel driving circuit 200.

[0068] In an exemplary embodiment, the light-emitting device 300 of each sub-pixel includes a first electrode 1, a first light-emitting material layer 4, a charge generation layer 6, a second light-emitting material layer 9, a second electrode 12, and a capping layer 14, which are sequentially stacked in a direction away from the base substrate 100. In the light-emitting device of a sub-pixel, the charge generation layer 6 is short-circuited with one of the first electrode 1 and the second electrode 12, so that part of the light-emitting material layer in the sub-pixel emits light, thereby reducing the power consumption of the display substrate of the embodiment of the present invention.

[0069] In an exemplary embodiment, Figure 3 As shown, the first sub-pixel P1 may be a red (R) sub-pixel, the second sub-pixel P2 may be a green (G) sub-pixel, and the third sub-pixel P3 may be a blue (B) sub-pixel.

[0070] Figure 4 FIG. 1 is an enlarged view of a light emitting device in a first sub-pixel of a display substrate according to an embodiment of the present invention. Figure 3 and Figure 4 As shown, in the light emitting device 300 of the first sub-pixel P1, the light emitting device 300 further includes: a short-circuit structure layer 15, the short-circuit structure layer 15 includes a conductive material layer 151, and the conductive material layer 151 short-circuits the charge generation layer 6 and the second electrode 12. When the first sub-pixel P1 is lit, the electrons emitted by the second electrode 12 are not input into the second light emitting material layer 9, so that the second light emitting material layer 9 does not emit light, and only the first light emitting material layer 4 emits light, thereby reducing the power consumption of the first sub-pixel P1.

[0071] In an exemplary embodiment, Figure 3 and Figure 4 As shown, the conductive material layer 151 covers part of the peripheral side of the charge generation layer 6, the peripheral side of the second light-emitting material layer 9, and at least part of the second electrode 12. For example, the conductive material layer 151 includes a side wall, a portion of the side wall of the conductive material layer 151 covers part of the peripheral side of the charge generation layer 6, and another portion of the side wall of the conductive material layer 151 covers the peripheral side of the second light-emitting material layer 9 and part of the peripheral side of the second electrode 12, so that the conductive material layer 151 short-circuits the charge generation layer 6 and the second electrode 12.

[0072] In an exemplary embodiment, the material of the conductive material layer 151 may be a metal or a conductive oxide. For example, the metal may include an alloy such as magnesium aluminum alloy (MgAl), magnesium aluminum alloy (MgAg), lithium aluminum alloy (LiAl), or a single metal such as magnesium, aluminum, lithium, silver, etc. The conductive oxide may include at least one of indium tin oxide (ITO), indium zinc oxide (IZO), indium gallium oxide (IGO), gallium zinc oxide (GZO), zinc oxide (ZnO), indium oxide (In2O3), and aluminum zinc oxide (AZO).

[0073] In an exemplary embodiment, Figure 3 and Figure 4 As shown, the short-circuit structure layer 15 further includes an insulating material layer 152, which is located on the side of the conductive material layer 151 close to the base substrate 100. The insulating material layer 152 covers the peripheral side of the charge generation layer 6, the peripheral side of the first light-emitting material layer 4, and the first electrode 1. The insulating material layer 152 insulates the conductive material layer 151 from the first electrode 1 to prevent the conductive material layer 151 from short-circuiting the charge generation layer 6 and the first electrode 1. Among them, a first opening is provided in the short-circuit structure layer 15 composed of an insulating material layer 152 and a conductive material layer 151, and the first electrode 1, the first light-emitting material layer 4, the charge generation layer 6 and the second light-emitting material layer 9 are located in the first opening. The short-circuit structure layer 15 covers the first electrode 1, the first light-emitting material layer 4, the charge generation layer 6 and the second light-emitting material layer 9. In the light-emitting device 300 of the first sub-pixel P1, the short-circuit structure layer 15 serves as a pixel defining layer, which disconnects the first electrode 1, the first light-emitting material layer 4, the second light-emitting material layer 9 and the charge generation layer 6 in adjacent sub-pixels, so that the first electrode 1, the first light-emitting material layer 4, the second light-emitting material layer 9 and the charge generation layer 6 in adjacent sub-pixels are insulated from each other.

[0074] In an exemplary embodiment, the material of the insulating material layer 152 may be an inorganic insulating material or an organic insulating material. For example, the inorganic insulating material may include polysiloxane, silicon nitride, silicon oxide, silicon oxynitride, etc. The organic insulating material may be a resin.

[0075] In an exemplary embodiment, the film structure of the light-emitting device of the second sub-pixel P2 is substantially the same as that of the light-emitting device of the first sub-pixel P1, and in the light-emitting device of the second sub-pixel P2, the conductive material layer of the short-circuit structure layer short-circuits the charge generation layer and the second electrode. When the sub-pixel is lit, the electrons emitted by the second electrode are not input into the second light-emitting material layer, so that the second light-emitting material layer does not emit light, and only the first light-emitting material layer emits light, thereby reducing the power consumption of the sub-pixel, and the present invention will not be repeated here.

[0076] Figure 5 FIG. 1 is an enlarged view of a light emitting device in a third sub-pixel of a display substrate according to an embodiment of the present invention. Figure 3 and Figure 5 As shown, in the light emitting device 300 of the third sub-pixel P3, the light emitting device 300 further includes: a short-circuit structure layer 15, the short-circuit structure layer 15 includes a conductive material layer 151, and the conductive material layer 151 short-circuits the charge generation layer 6 and the first electrode 1. When the third sub-pixel P3 is lit, the holes emitted by the first electrode 1 are not input into the first light emitting material layer 4, so that the first light emitting material layer 4 does not emit light, and only the second light emitting material layer 9 emits light, thereby reducing the power consumption of the third sub-pixel P3.

[0077] In an exemplary embodiment, Figure 3 and Figure 5 As shown, the conductive material layer 151 covers the peripheral side of the charge generation layer 6, the peripheral side of the first light-emitting material layer 4, and the first electrode 1. For example, the conductive material layer 151 includes a side wall, a portion of the side wall of the conductive material layer 151 covers a portion of the peripheral side of the charge generation layer 6, and another portion of the side wall of the conductive material layer 151 covers the peripheral side of the first light-emitting material layer 4 and the first electrode 1, so that the conductive material layer 151 short-circuits the charge generation layer 6 and the first electrode 1.

[0078] In an exemplary embodiment, Figure 3 and Figure 5 As shown, the short-circuit structure layer 15 further includes an insulating material layer 152, and the insulating material layer 152 is located on the side of the conductive material layer 151 close to the base substrate 100. The insulating material layer 152 covers the peripheral side of the second light-emitting material layer 9 and covers part of the second electrode 12. The insulating material layer 152 insulates the conductive material layer 151 from the second electrode 12, respectively, to prevent the conductive material layer 151 from short-circuiting the charge generation layer 6 and the second electrode 12. Among them, a first opening is provided in the short-circuit structure layer 15 composed of an insulating material layer 152 and a conductive material layer 151, and the first electrode 1, the first light-emitting material layer 4, the charge generation layer 6 and the second light-emitting material layer 9 are located in the first opening. The short-circuit structure layer 15 covers the first electrode 1, the first light-emitting material layer 4, the charge generation layer 6 and the second light-emitting material layer 9. In the light-emitting device 300 of the third sub-pixel P3, the short-circuit structure layer 15 serves as a pixel defining layer, which disconnects the first electrode 1, the first light-emitting material layer 4, the second light-emitting material layer 9 and the charge generation layer 6 in adjacent sub-pixels, so that the first electrode 1, the first light-emitting material layer 4, the second light-emitting material layer 9 and the charge generation layer 6 in adjacent sub-pixels are insulated from each other.

[0079] Figure 6 The top view of each sub-pixel in the display substrate of the embodiment of the present invention is shown in FIG. Figure 1 .like Figure 6As shown, a first opening is provided in the short-circuit structure layer 15, and the first electrode 1, the first light-emitting material layer 4, the charge generation layer 6 and the second light-emitting material layer 9 are located in the first opening, and the short-circuit structure layer 15 covers the first electrode 1, the first light-emitting material layer 4, the charge generation layer 6 and the second light-emitting material layer 9. In the direction parallel to the substrate, the cross-section of the short-circuit structure layer can be annular. In the light-emitting device 300 of the first sub-pixel P1, the light-emitting device 300 of the second sub-pixel P2 and the light-emitting device 300 of the third sub-pixel P3, the short-circuit structure layer 15 is equivalent to the role of the pixel defining layer, disconnecting the first electrode 1, the first light-emitting material layer 4, the second light-emitting material layer 9 and the charge generation layer 6 in the adjacent sub-pixels, so that the first electrode 1, the first light-emitting material layer 4, the second light-emitting material layer 9 and the charge generation layer 6 in the adjacent sub-pixels are insulated from each other.

[0080] Fig.13 The top view of each sub-pixel in the display substrate of the embodiment of the present invention is shown in FIG. Figure 2 .like Fig.13 As shown, each sub-pixel further includes: a pixel defining layer 18, a second opening is provided in the pixel defining layer 18, and the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer are located in the second opening. A notch is provided on the side of the pixel defining layer 18, and the notch exposes part of the circumference of the first electrode, part of the circumference of the first light-emitting material layer, part of the circumference of the charge generation layer and part of the circumference of the second light-emitting material layer. The short-circuit structure layer 15 is provided in the same layer as the pixel defining layer 18, and the short-circuit structure layer 15 is provided in the notch, and the short-circuit structure layer 15 covers the exposed part of the circumference of the first electrode, part of the circumference of the first light-emitting material layer, part of the circumference of the charge generation layer and part of the circumference of the second light-emitting material layer. In the direction parallel to the base substrate, the cross-section of the short-circuit structure layer 15 can be fan-shaped.

[0081] In an exemplary embodiment, Figure 1 As shown, the color filter layer 400 is located on the side of the plurality of sub-pixels away from the base substrate; the color filter layer includes a plurality of color blocks 16 of different colors, and the orthographic projection of each sub-pixel on the base substrate is located within the orthographic projection of one color block on the base substrate. The color blocks of the color filter layer are used to block some colors of light and allow light of a specific color to pass through, thereby converting the light emitted by the sub-pixel into light of a specific color. In the first sub-pixel P1, the color block 16 only allows red light to pass through, thereby converting the light emitted by the second sub-pixel P1 into red light; in the second sub-pixel P2, the color block 16 only allows green light to pass through, thereby converting the light emitted by the second sub-pixel P2 into green; in the third sub-pixel P3, the color block 16 only allows blue light to pass through, thereby converting the light emitted by the third sub-pixel P3 into blue.

[0082] In an exemplary embodiment, the light emitted by the first luminescent material layer and the light emitted by the second luminescent material layer are mixed to form white light.

[0083] In an exemplary embodiment, the first light-emitting material layer includes a first sub-light-emitting material layer and a second sub-light-emitting material layer sequentially stacked in a direction away from the base substrate, and light emitted by the sub-light-emitting material layer and light emitted by the second sub-light-emitting material layer are mixed to produce yellow light.

[0084] In an exemplary embodiment, the first electrodes 1 in each sub-pixel are insulated from each other. The second electrodes 12 in each sub-pixel can be connected as one. The first light-emitting material layer, the second light-emitting material layer and the charge generation layer of two adjacent sub-pixels can be disconnected by a short-circuit structure layer 15 disposed between the two adjacent sub-pixels, that is, the first light-emitting material layer, the second light-emitting material layer and the charge generation layer in each sub-pixel are also insulated from each other.

[0085] The technical solution of the embodiment of the present invention is further explained below by the preparation process of the display substrate in this embodiment. Among them, the "composition process" mentioned in this embodiment includes deposition of film layer, coating of photoresist, mask exposure, development, etching, stripping of photoresist and other processes, the "photolithography process" mentioned in this embodiment includes coating of film layer, mask exposure, development and other processes, and the evaporation, deposition, coating, coating and the like mentioned in this embodiment are all mature preparation processes in the relevant technology.

[0086] Figures 7-10 The schematic diagram of the manufacturing process of the display substrate in this embodiment. The manufacturing process of the display substrate includes:

[0087] (1) Forming a first electrode and a third conductive material layer pattern. The first electrode and the third conductive material layer pattern comprises: forming a pixel driving circuit 200 on a base substrate 100, then depositing a first conductive film on the pixel driving circuit 200, patterning the first conductive film by a patterning process, forming a first electrode a101, a first electrode b102 and a first electrode c103 that are disconnected from each other on the pixel driving circuit 200, then depositing a second conductive film covering the first electrode c103 on the pixel driving circuit 200, patterning the second conductive film by a patterning process, forming a third conductive material layer 151C covering both side edges of the first electrode c103 on the first electrode c103, as shown in FIG. Figure 7 The material of the first electrode c103 is the same as that of the third conductive material layer 151C.

[0088] (2) Forming an insulating material layer pattern. Forming the insulating material layer pattern includes: depositing a layer of insulating material film on the substrate 100 having the above structure, patterning the insulating material film through a patterning process, forming a first insulating material layer 152A covering both side edges of the first electrode a101 on the first electrode a101; forming a second insulating material layer 152B covering both side edges of the first electrode b102 on the first electrode b102; forming a third insulating material layer 152C covering the third conductive material layer 151C on both side edges of the first electrode c103, such as Figure 8 shown.

[0089] (3) Forming patterns of the first conductive material layer and the second conductive material layer. The forming patterns of the first conductive material layer and the second conductive material layer include: depositing a second conductive film on the substrate 100 having the above structure, patterning the second conductive film by a patterning process, forming a first conductive material layer 151A covering the first insulating material layer 152A on both side edges of the first electrode a101; forming a second conductive material layer 151B covering the second insulating material layer 152B on both side edges of the first electrode b101, such as Fig. 9 As shown. The first conductive material layer 151A and the first insulating material layer 152A form a first short-circuit structure layer 15A; the first short-circuit structure layer 15A exposes the middle part of the first electrode a101; the second conductive material layer 151B and the second insulating material layer 152B form a second short-circuit structure layer 15B, and the second short-circuit structure layer 15B exposes the middle part of the first electrode b102; the third conductive material layer 151C and the third insulating material layer 152C form a third short-circuit structure layer 15C, and the third short-circuit structure layer 15C exposes the middle part of the first electrode c103. The material of the first conductive material layer 151A can be the same as that of the first electrode a101; the material of the second conductive material layer 151B can be the same as that of the first electrode b102.

[0090] (4) forming a first light-emitting material layer, a charge generation layer, a second light-emitting material layer, and a second electrode pattern. The formation of the first light-emitting material layer, the charge generation layer, the second light-emitting material layer, and the second electrode pattern includes: sequentially forming a first light-emitting material layer 4, a charge generation layer 6, a second light-emitting material layer 9, and a second electrode 12 on the middle portion of the first electrode a101, the middle portion of the first electrode b102, and the middle portion of the first electrode c103, as shown in FIG. Fig.10As shown. The first conductive material layer 151A in the first short-circuit structure layer 15A short-circuits the charge generation layer on the first electrode a101 and the second electrode 12 on the first electrode a101. The second conductive material layer 151B in the second short-circuit structure layer 15B short-circuits the charge generation layer on the first electrode b102 and the second electrode 12 on the first electrode b102. The third conductive material layer 151C in the third short-circuit structure layer 15C short-circuits the first electrode c103 and the charge generation layer on the first electrode c103.

[0091] Fig.11 A cross-sectional view of a pixel unit of a display substrate according to an embodiment of the present invention Figure 2 .like Fig.11 As shown, in the light-emitting device 300 of the third sub-pixel P3, the third sub-pixel P3 further includes: a pixel defining layer 18, a second opening is provided in the pixel defining layer 18, the first electrode 1, the first light-emitting material layer 4, the charge generation layer 6 and the second light-emitting material layer 9 are located in the second opening, that is, the peripheral side of the first electrode 1, the peripheral side of the first light-emitting material layer 4, the peripheral side of the charge generation layer 6 and the peripheral side of the second light-emitting material layer 9 are not provided with a short-circuit structure layer 15. A first through-hole 16 is provided in the first light-emitting material layer 4, and the first through-hole 16 penetrates the first light-emitting material layer 4 in a direction perpendicular to the substrate, and the charge generation layer 6 is connected to the first electrode 1 through the first through-hole 16, so that the charge generation layer 6 is short-circuited with the first electrode 1. When the third sub-pixel P3 is lit, the holes emitted by the first electrode 1 are not input into the first light-emitting material layer 4, so that the first light-emitting material layer 4 does not emit light, and only the second light-emitting material layer 9 emits light, thereby reducing the power consumption of the third sub-pixel P3.

[0092] Fig.12 A cross-sectional view of a pixel unit of a display substrate according to an embodiment of the present invention Figure 3 .like Fig.12As shown, in the light-emitting device 300 of the first sub-pixel P1 and the second sub-pixel P2, the first sub-pixel P1 and the second sub-pixel P2 both include: a pixel defining layer 18, a second opening is provided in the pixel defining layer 18, the first electrode 1, the first light-emitting material layer 4, the charge generation layer 6 and the second light-emitting material layer 9 are located in the second opening, that is, the peripheral side of the first electrode 1, the peripheral side of the first light-emitting material layer 4, the peripheral side of the charge generation layer 6 and the peripheral side of the second light-emitting material layer 9 are not provided with a short-circuit structure layer 15. A second through hole 17 is provided in the second light-emitting material layer 9, and the second through hole 17 penetrates the second light-emitting material layer 9 in a direction perpendicular to the base substrate, and the charge generation layer 6 is connected to the second electrode 12 through the second through hole 17, so that the charge generation layer 6 and the second electrode 12 are short-circuited. When the first subpixel P1 and the second subpixel P2 are lit, the electrons emitted by the second electrode 12 are not input into the second light-emitting material layer 9, so that the second light-emitting material layer 9 does not emit light, and only the first light-emitting material layer 4 emits light, thereby reducing the power consumption of the first subpixel P1 and the second subpixel P2.

[0093] The embodiment of the present invention further provides a display device, comprising any of the above-mentioned display substrates. The display device includes a mobile phone, a tablet computer, a smart wearable product (such as a smart watch, a bracelet, etc.), a personal digital assistant (PDA), a car computer, etc. The embodiment of the present application does not impose any special restrictions on the specific form of the above-mentioned foldable display device.

[0094] An embodiment of the present invention further provides a method for preparing a display substrate, comprising:

[0095] A plurality of sub-pixels are formed on one side of the substrate, each of the sub-pixels comprising at least: a first electrode, a first light-emitting material layer, a charge generation layer, a second light-emitting material layer and a second electrode sequentially stacked in a direction away from the substrate;

[0096] The charge generation layer is short-circuited with one of the first electrode and the second electrode.

[0097] 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.

[0098] 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 and a plurality of sub-pixels located on one side of the substrate, each of the sub-pixels comprising: a first electrode, a first light-emitting material layer, a charge generation layer, a second light-emitting material layer and a second electrode stacked in sequence in a direction away from the substrate, the charge generation layer being short-circuited with one of the first electrode and the second electrode; the sub-pixel further comprising: a short-circuit structure layer, the short-circuit structure layer being located on the peripheral side of the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer; the short-circuit structure layer comprising a conductive material layer and an insulating material layer, the conductive material layer short-circuiting the charge generation layer with the first electrode, and the insulating material layer insulating the conductive material layer from the second light-emitting material layer and the second electrode, respectively; or, the conductive material layer short-circuiting the charge generation layer with the second electrode, and the insulating material layer insulating the conductive material layer from the first light-emitting material layer and the first electrode, respectively.

2. The display substrate according to claim 1, characterized in that: A first opening is provided in the short-circuit structure layer, and the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer are located in the first opening, and the short-circuit structure layer covers the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer.

3. The display substrate according to claim 1, characterized in that: Each of the sub-pixels also includes: a pixel defining layer, a second opening is provided in the pixel defining layer, the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer are located in the second opening, a notch is provided on the side of the pixel defining layer, the short-circuit structure layer is provided on the same layer as the pixel defining layer, and the short-circuit structure layer is provided in the notch, and the short-circuit structure layer covers part of the circumference of the first electrode, part of the circumference of the first light-emitting material layer, part of the circumference of the charge generation layer and part of the circumference of the second light-emitting material layer.

4. The display substrate according to claim 1, characterized in that: The conductive material layer is metal or conductive oxide.

5. The display substrate according to claim 1, characterized in that: The insulating material layer is an inorganic insulating material or an organic insulating material.

6. The display substrate according to any one of claims 1 to 5, characterized in that: The light emitted by the first luminescent material layer and the light emitted by the second luminescent material layer are mixed to form white light.

7. The display substrate according to any one of claims 1 to 5, characterized in that: The first light-emitting material layer includes a first sub-light-emitting material layer and a second sub-light-emitting material layer stacked in sequence in a direction away from the base substrate, and light emitted by the first sub-light-emitting material layer and light emitted by the second sub-light-emitting material layer are mixed to produce yellow light.

8. The display substrate according to any one of claims 1 to 5, characterized in that: It also includes a color filter layer, which is located on the side of the multiple sub-pixels away from the base substrate; the color filter layer includes multiple color resist blocks of different colors, and the orthographic projection of each sub-pixel on the base substrate is located within the orthographic projection of a color resist block on the base substrate.

9. A display device, characterized in that: The display substrate comprises any one of claims 1 to 8.

10. A method for preparing a display substrate, characterized in that: include: A plurality of sub-pixels are formed on one side of the substrate, each of the sub-pixels comprising at least: a first electrode, a first light-emitting material layer, a charge generation layer, a second light-emitting material layer and a second electrode sequentially stacked in a direction away from the substrate; Among them, the charge generation layer is short-circuited with one of the first electrode and the second electrode; the sub-pixel also includes: a short-circuit structure layer, which is located on the surrounding side of the first electrode, the first light-emitting material layer, the charge generation layer and the second light-emitting material layer; the short-circuit structure layer includes a conductive material layer and an insulating material layer, the conductive material layer short-circuits the charge generation layer with the first electrode, and the insulating material layer insulates the conductive material layer from the second light-emitting material layer and the second electrode respectively; or, the conductive material layer short-circuits the charge generation layer with the second electrode, and the insulating material layer insulates the conductive material layer from the first light-emitting material layer and the first electrode respectively.

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