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CN119816110B - Display Panel and its Manufacturing Method - Google Patents

Display Panel and its Manufacturing Method

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Publication number
CN119816110B
CN119816110B CN202411998618.1A CN202411998618A CN119816110B CN 119816110 B CN119816110 B CN 119816110B CN 202411998618 A CN202411998618 A CN 202411998618A CN 119816110 B CN119816110 B CN 119816110B
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China
Prior art keywords
partition structure
light
layer
cathode
electrode
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CN202411998618.1A
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Chinese (zh)
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CN119816110A (en
Inventor
周秀峰
谢志生
唐杨玲
梁琴
叶利丹
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HKC Co Ltd
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HKC Co Ltd
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Publication of CN119816110A publication Critical patent/CN119816110A/en
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Abstract

The application discloses a display panel and a manufacturing method thereof, wherein the display panel comprises a substrate, a pixel definition layer and a light-emitting unit, the display panel further comprises a partition structure, the partition structure is positioned in a non-opening area and arranged on the pixel definition layer, the light-emitting unit comprises a bottom electrode, a light-emitting functional layer and a top electrode, the partition structure is used for partitioning the bottom electrodes of two adjacent light-emitting units when the bottom electrodes are deposited on the whole surface, the partition structure is formed by adopting a negative organic adhesive material, and the radial width of the partition structure is gradually reduced from the direction that the partition structure is close to the substrate. The application utilizes the partition structure to partition the bottom electrodes of the light-emitting units, unnecessary bottom electrode materials are not required to be removed through an etching process, and the influence of the etching process on the bottom electrodes is reduced.

Description

Display panel and manufacturing method thereof
Technical Field
The application relates to the technical field of display, in particular to a display panel and a manufacturing method thereof.
Background
An OLED (Organic LIGHT EMITTING Diode) display device is widely used in various fields because it has a light weight, a wide viewing angle, a fast response, a low temperature resistance, a high luminous efficiency, and a capability of manufacturing a flexible display screen that is curved. Due to the increasing maturity of mass production technology, the OLED display panel becomes a mainstream reality panel gradually.
The conventional organic light emitting display panel mainly comprises two types, namely an organic light emitting display panel which is arranged in a positive mode, wherein a light emitting unit in the organic light emitting display panel which is arranged in a positive mode comprises an anode, a light emitting function layer and a cathode which are sequentially stacked on a substrate, and an organic light emitting display panel which is arranged in an inverted mode and comprises a cathode, a light emitting function layer and an anode which are sequentially stacked on the substrate. For the organic light emitting display panel arranged in the front, the active metal in the cathode is easy to be corroded by water and oxygen, so that the service life of the display panel is reduced, and for the organic light emitting display panel arranged in the back, the active metal in the cathode is easy to be oxidized in the process or has the problems of process residue and the like, so that the luminous efficiency of the organic light emitting display panel arranged in the back is low. In this regard, there is a need in the art for a solution to the above-described problems.
Disclosure of Invention
The application aims to provide a display panel and a manufacturing method thereof, wherein when a bottom electrode is formed by a light-emitting unit, the bottom electrodes of the light-emitting units are separated by the separation structure, so that the bottom electrodes of the light-emitting units are not connected with each other, redundant bottom electrode materials are not required to be removed by an etching process, and the influence of the etching process on the bottom electrode is reduced.
The application discloses a display panel which comprises a substrate, a pixel definition layer and a light-emitting unit, wherein the pixel definition layer is arranged on the substrate and is provided with a plurality of opening areas, the light-emitting unit is arranged on the substrate and is positioned in the opening areas, the display panel further comprises a partition structure, the partition structure is positioned in a non-opening area and is arranged on the pixel definition layer, the light-emitting unit comprises a bottom electrode, a light-emitting functional layer and a top electrode, the bottom electrode is arranged on the substrate, the light-emitting functional layer is arranged on the bottom electrode, the top electrode is arranged on the light-emitting functional layer, the partition structure is used for partitioning the bottom electrodes of two adjacent light-emitting units when the bottom electrode is deposited in an integral mode, the partition structure is formed by adopting a negative organic adhesive material, and the radial width of the partition structure is gradually reduced in the direction that the partition structure is close to the substrate.
Optionally, the partition structure is arranged around the opening area, the cross section of the partition structure is in an inverted trapezoid shape, one side of the partition structure, which is far away from the substrate, is a top surface, one side of the partition structure, which is close to the substrate, is a bottom surface, and an included angle between the top surface and the side surface is 30-70 degrees, or an included angle between the side surface and the top surface of the pixel definition layer is 30-70 degrees.
Optionally, the thickness of the partition structure is greater than or equal to 0.01um and less than or equal to 0.06um, the radial width of the partition structure is less than or equal to the radial width of the pixel definition layer at the position of the non-opening area, and the negative organic adhesive material comprises polyimide material, epoxy resin material or polyacrylate material.
Optionally, the thickness of the bottom electrode is greater than or equal to 0.01um and less than or equal to 0.03um, the thickness of the partition structure is greater than or equal to 0.02um and less than or equal to 0.05um, and in the partition structure, an included angle between the top surface and the side surface is between 45 degrees and 60 degrees.
The light-emitting device comprises a substrate, a light-emitting unit, a light-emitting functional layer, a partition structure and a light-emitting function layer, wherein the light-emitting unit is arranged on the substrate, the light-emitting functional layer comprises a light-emitting electrode, the light-emitting function layer comprises an electron transmission layer, a light-emitting layer and a hole transmission layer, the electron transmission layer is arranged on the cathode, the light-emitting layer is arranged on the electron transmission layer, the hole transmission layer is arranged on the light-emitting layer, the anode is arranged on the hole transmission layer, and the partition structure is used for partitioning cathodes of two adjacent light-emitting units when the cathodes are deposited in a whole surface.
Optionally, the display panel further includes a cathode auxiliary electrode formed of a transparent metal oxide material, the cathode auxiliary electrode is disposed under the cathode and electrically connected to the cathode, and the cathode auxiliary electrodes of two adjacent light emitting units are separated by the pixel defining layer.
Optionally, the cathode further comprises a cathode redundant electrode, the cathode redundant electrode is arranged on the partition structure, the cathode and the cathode redundant electrode are disconnected through the partition structure, and the partition structure is further used for sequentially partitioning the electron transport layer, the light emitting layer and the hole transport layer between the opening area and the non-opening area when the whole surfaces of the electron transport layer, the light emitting layer and the hole transport layer are deposited.
The application discloses a manufacturing method of a display panel, which comprises the following steps:
providing a substrate base plate;
Forming a pixel definition layer on the substrate base plate, and patterning the pixel definition layer to form a plurality of opening areas;
Forming a partition structure on the pixel defining layer;
depositing a bottom electrode material on the whole surface, wherein the partition structure is used for partitioning the bottom electrodes of two adjacent light-emitting units;
Sequentially forming a light-emitting functional layer and a top electrode in the opening area to form a plurality of light-emitting units;
The partition structure is formed by adopting a negative organic adhesive material, and the radial width of the partition structure gradually decreases from the direction that the partition structure is close to the substrate.
Optionally, the step of forming a pixel defining layer on the substrate and patterning the pixel defining layer to form a plurality of opening areas includes:
Depositing a cathode auxiliary electrode material on the substrate, patterning and forming a cathode auxiliary electrode in the opening area;
And depositing and patterning a pixel definition layer on the cathode auxiliary electrodes, wherein the cathode auxiliary electrodes of two adjacent light emitting units are separated by the pixel definition layer, and a plurality of opening areas are formed, and the cathode auxiliary electrodes are exposed from the opening areas.
Optionally, the step of sequentially forming a light emitting functional layer and a top electrode in the opening area to form a plurality of light emitting units includes:
depositing the luminescent functional layer material on the whole surface, and isolating luminescent functional layers of two adjacent luminescent units through an overhang structure;
depositing anodes on the whole surface to form a plurality of the light emitting units;
the light-emitting functional layer comprises an electron transmission layer, a light-emitting layer and a hole transmission layer, wherein the electron transmission layer is arranged on the cathode, the light-emitting layer is arranged on the electron transmission layer, the hole transmission layer is arranged on the light-emitting layer, and the anode is arranged on the hole transmission layer;
The cathode is made of one or two of magnesium material and silver material, the cathode is a light-transmitting electrode, the anode is made of reflective metal material, the plurality of light-emitting units share the anode, and light emitted by the light-emitting units is emitted from one side of the substrate.
The application forms the partition structure by adopting the negative organic adhesive material, firstly, the negative organic adhesive material can be used for forming the partition structure with the upper part width and the lower part narrow in the exposure and development process, and secondly, the negative organic adhesive material has stronger insulating property, and even under the condition that the angle is not controlled in the whole deposition process of the bottom electrode, the bottom electrode is contacted with the partition structure, the partition structure can also play an insulating role, and the problem of electrical crosstalk between the bottom electrodes of adjacent light-emitting units is prevented. According to the application, the partition structure is arranged, so that when the bottom electrodes are formed by the light-emitting units, the partition structure is utilized to partition the bottom electrodes of the light-emitting units, and the bottom electrodes of the light-emitting units are not connected with each other. In the process of forming the bottom electrode, the redundant bottom electrode material is not required to be removed through an etching process, and the next process of the luminous functional layer can be directly carried out after the bottom electrode is deposited on the whole surface, so that the influence of the etching process on the bottom electrode is reduced. Particularly, when the bottom electrode comprises an active metal material, the problems of oxidation, residue and the like of the active metal in an etching process are avoided, a film interface between the bottom electrode and the light-emitting functional layer is improved, the light-emitting efficiency of the light-emitting unit is improved, and the display effect of the display panel is improved.
Drawings
The accompanying drawings, which are included to provide a further understanding of embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. It is evident that the figures in the following description are only some embodiments of the application, from which other figures can be obtained without inventive effort for a person skilled in the art. In the drawings:
fig. 1 is a schematic view of a display panel according to a first embodiment of the present application;
FIG. 2 is a schematic cross-sectional view of FIG. 1 along cut line AA;
FIG. 3 is a schematic view of a partition structure of the present application;
Fig. 4 is a schematic view of a light emitting unit of the present application;
FIG. 5 is a schematic cross-sectional view of a second display panel of the present application;
FIG. 6 is a schematic diagram illustrating steps of a method for fabricating a display panel according to the present application;
fig. 7 is a schematic diagram of a manufacturing process of the display panel of the present application.
Wherein, 100, display panel, 101, opening area, 102, non-opening area, 110, substrate base plate, 120, pixel definition layer, 130, light emitting unit, 131, anode, 132, light emitting function layer, 1321, electron transport layer, 1322, light emitting layer, 1323, hole transport layer, 1324, electron injection layer, 1325, hole blocking layer, 1326, electron blocking layer, 1327, hole injection layer, 133, cathode, 134, cathode auxiliary electrode, 135, cathode redundancy part, 140, partition structure, 150, driving circuit layer, 200, display device, 210, driving circuit.
Detailed Description
It is to be understood that the terminology used herein, the specific structural and functional details disclosed are merely representative for the purpose of describing particular embodiments, but that the application may be embodied in many alternate forms and should not be construed as limited to only the embodiments set forth herein.
In the description of the present application, the terms "first", "second" are used for descriptive purposes only and are not to be construed as indicating relative importance or implicitly indicating the number of technical features indicated. Thus, unless otherwise indicated, features defining "a first", "a second", and "a plurality" may include one or more of such features explicitly or implicitly, and "a plurality" means two or more. In addition, terms of the azimuth or positional relationship indicated by "upper", "lower", "left", "right", "vertical", "horizontal", etc., are described based on the azimuth or relative positional relationship shown in the drawings, and are merely for convenience of description of the present application, and do not indicate that the apparatus or element referred to must have a specific azimuth, be constructed and operated in a specific azimuth, and thus should not be construed as limiting the present application. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.
The application is described in detail below with reference to the attached drawings and alternative embodiments.
Fig. 1 is a schematic view of a first display panel of the present application, fig. 2 is a schematic view of a section along a cutting line AA in fig. 1, and referring to fig. 1-2, the display panel 100 disclosed in the present application includes a substrate 110, a pixel definition layer 120 and a light emitting unit 130, the pixel definition layer 120 is disposed on the substrate 110, and a plurality of opening regions 101 are disposed, the light emitting unit 130 is disposed on the substrate 110 and is located in the opening regions 101, the display panel 100 further includes a partition structure 140, the partition structure 140 is located in a non-opening region 102 and is disposed on the pixel definition layer 120, the light emitting unit 130 includes a bottom electrode, a light emitting functional layer 132 and a top electrode, the bottom electrode is disposed on the substrate 110, the light emitting functional layer 132 is disposed on the top electrode, and the partition structure 140 is used for partitioning bottom electrodes of two adjacent light emitting units 130 when the bottom electrode is deposited on the whole surface, wherein the partition structure 140 is formed by using a negative photoresist, and the partition structure 140 gradually decreases from the radial direction of the substrate 140.
The partition structure 140 is formed by adopting the negative organic adhesive material, firstly, the partition structure 140 with the upper width and the lower narrow part can be formed by utilizing the negative organic adhesive material in the exposure and development process, and secondly, the partition structure 140 can play an insulating role to prevent the problem of electrical crosstalk between the bottom electrodes of the adjacent light emitting units 130 by utilizing the negative organic adhesive material with stronger insulating property even if the bottom electrode is contacted with the partition structure 140 under the condition that the angle is not controlled in the whole deposition process of the bottom electrode. In the present application, the partition structure 140 is provided, so that the bottom electrodes of the plurality of light emitting units 130 are not connected to each other by the partition structure 140 when the bottom electrodes of the light emitting units 130 are formed. In the process of forming the bottom electrode, the redundant bottom electrode material is not required to be removed through an etching process, and the next process of the light-emitting functional layer 132 can be directly carried out after the bottom electrode is deposited on the whole surface, so that the influence of the etching process on the bottom electrode is reduced. Particularly, when the bottom electrode includes the active metal material, the problems of oxidation, residue and the like of the active metal in the etching process are avoided, the interface of the film layer between the bottom electrode and the light emitting functional layer 132 is improved, the light emitting efficiency of the light emitting unit 130 is improved, and the display effect of the display panel 100 is improved.
Specifically, the negative organic adhesive material comprises polyimide material, epoxy resin material or polyacrylate material, and the like, and the material is characterized in that the irradiated part is converged and crosslinked to be used as a functional structure, and the non-irradiated negative photosensitive organic material part can be removed by a developing solution reaction in a subsequent process. Specifically, after a layer of negative organic gel material is coated on the substrate 110, due to the photosensitive property of the negative organic gel material, after the negative organic gel material is coated to form a film, the light irradiation part is converged and crosslinked, so that the surface irradiation is stronger, the polymerization and crosslinking are easier, the light intensity in a deeper place is gradually weakened, the polymerization and crosslinking degree is inferior to that of the surface, and the lower part with the weakened photosensitive strength is reacted in the developing process, so that a structure with wide upper part and narrow lower part is formed. It will be appreciated that the wide top and narrow bottom configuration of the partition structure 140 of the present application is integrally formed, and that two or more layers are not required, and that the partition structure 140 is formed by etching the widths of the different layers.
Specifically, the partition structure 140 is disposed around the opening area 101, and the cross-sectional shape of the partition structure 140 is an inverted trapezoid.
In this embodiment, the cross-sectional shape of the partition structure 140 refers to the cross-section of the partition structure 140 on the connection line between two adjacent light emitting units 130, and the partition structure 140 adopts an inverted trapezoid shape, so that when the bottom electrode is deposited on the whole surface, the portion of the bottom electrode material on the pixel defining layer 120 is separated from the bottom electrode on the opening area 101 by the wider upper portion, and thus the bottom electrode material on the pixel defining layer 120 does not need to be etched later, and the problems caused by the etching process mentioned above are avoided.
Fig. 3 is a schematic view of a partition structure according to the present application, referring to fig. 3, in order to meet the requirement of partitioning a bottom electrode, it is necessary to control an angle of an inverted trapezoid, and a side of the partition structure 140 away from the substrate 110 is a top surface, and a side of the partition structure 140 close to the substrate 110 is a bottom surface, where an included angle between the top surface and the side is between 30 degrees and 70 degrees. When the included angle between the top surface and the side surface approaches 90 degrees, the blocking effect is poor, and during the deposition process of the bottom electrode material, a film layer is easily deposited on the side surface of the blocking structure 140, so that the bottom electrode material is continuously distributed from the pixel defining layer 120 to the side surface and the top surface of the blocking structure 140. When the angle between the top surface and the side surface is smaller, the concave effect of the side surface is more remarkable, and when the bottom electrode material is deposited, it is difficult to form a continuous film layer on the side surface of the partition structure 140, thereby realizing the partition effect. The smaller the included angle between the top surface and the side surface, the higher the process difficulty is, and the better the separation effect is between 30 degrees and 70 degrees and the easier the realization is.
In other words, when the top surface of the pixel defining layer 120 under the partition structure 140 is parallel to the top surface of the partition structure 140, the included angle θ between the side surface and the top surface of the pixel defining layer 120 is between 30 degrees and 70 degrees. Among them, 45 degrees to 60 degrees are preferable, and the process of the partition structure 140 and the partition effect on the light emitting unit 130 are combined to have a good realization value.
The deposition manner adopted by the bottom electrode and the light-emitting functional layer 132 in this embodiment may be an evaporation process, and in particular relates to a maskless evaporation process, which does not need to adopt a metal mask, and directly adopts an OH (overlapping) structure to enable the light-emitting functional layer 132. But this embodiment is also formed by subjecting the bottom electrode to maskless vapor deposition techniques.
Specifically, the display panel 100 of the present embodiment is a bottom light emitting display panel 100, wherein the bottom electrode is a light transmitting electrode, the top electrode is formed by using a reflective metal material, and the plurality of light emitting units 130 share the top electrode. The top electrode in this embodiment is a high-reflectivity opaque electrode, and the bottom electrode is a transparent electrode, so that all the light emitted by the light-emitting functional layer 132 is emitted from the bottom electrode, and the light emitted by the light-emitting unit 130 is emitted from one side of the substrate 110.
In this embodiment, the bottom electrode is patterned by the partition structure 140, and the light-emitting functional layer 132 is directly formed after the bottom electrode is patterned, so that other steps, such as etching steps, in the process of manufacturing the bottom electrode and the light-emitting functional layer 132 are reduced, and the film interface between the bottom electrode and the light-emitting functional layer 132 is greatly improved. Moreover, it is important that the process of the bottom electrode and the process of the light emitting functional layer 132 can be completed in the same vacuum environment, so that the problem of a film layer between the bottom electrode and the light emitting functional layer 132 is reduced.
It should be noted that, the bottom emission display panel 100 has the advantage that the anode 131 does not need to transmit light, so that the thickness of the anode 131 can be large and the entire surface can be formed, and all the light emitting units 130 share the entire surface of the anode 131, so that the resistance is lower compared with the top electrode of the top emission display panel 100 formed by indium tin oxide, and the components at different positions are more uniform, so that the voltage at different positions is avoided. Moreover, after the light emitting unit 130 completes the manufacturing process, the outgoing light of the light emitting unit 130 does not need to pass through the subsequent packaging layer, so that the material and the process of the packaging layer are more selective, and the light emitting unit 130 can be better packaged.
Fig. 4 is a schematic view of a light emitting unit of the present application, referring to fig. 4, and specifically, in order to further enhance the light emitting efficiency of the bottom emission display panel 100, the present embodiment is implemented by inverting the light emitting functional layer 132. Specifically, the top electrode is an anode 131, the bottom electrode is a cathode 133, the light-emitting functional layer 132 comprises an electron transport layer 1321, a light-emitting layer 1322 and a hole transport layer 1323, the electron transport layer 1321 is disposed on the cathode 133, the light-emitting layer 1322 is disposed on the electron transport layer 1321, the hole transport layer 1323 is disposed on the light-emitting layer 1322, and the anode 131 is disposed on the hole transport layer 1323.
The electron transport layer 1321 in this embodiment is connected to the cathode 133 through an electron injection layer 1324, and a hole blocking layer 1325 is further disposed between the electron transport layer 1321 and the light emitting layer 1322. The hole-transporting layer 1323 is connected to the anode 131 through a hole-injecting layer 1327, and an electron-blocking layer 1326 is further provided between the hole-transporting layer 1323 and the light-emitting layer 1322. In this case, the light emitting function layer 132 is inverted, that is, the electron transporting layer 1321 is disposed at a side close to the cathode 133, and the hole transporting layer 1323 is disposed at a side close to the anode 131. Diametrically opposed to the light emitting functional layer 132 in the light emitting unit 130 of the organic light emitting display panel 100 being disposed. In contrast, when the bottom emission display panel 100 uses the light emitting functional layer 132 as the normal arrangement, the light emitting efficiency of the bottom emission display panel 100 of the normal arrangement light emitting functional layer 132 is extremely low due to the influence of the pixel driving layer opening existing in the bottom emission display panel 100 due to the lower light emitting efficiency, which is not suitable for display. However, for the inverted bottom emission display panel 100, the light emission efficiency is affected by the work functions of the anode 131 and the cathode 133, and it is generally required that the work function of the anode 131 is relatively high and the work function of the cathode 133 is relatively low. When the anode 131 is selected as a reflective electrode and the cathode 133 is a transparent electrode, the work function of the anode 131 is lower and the work function of the cathode 133 is higher due to the characteristics of materials, resulting in lower luminous efficiency of the inverted bottom light emitting display panel 100.
In this regard, in the present embodiment, the cathode 133 is formed using one or both of a magnesium material and a silver material, the cathode 133 is formed using an active metal, and the light permeability is achieved by making the active metal thin. An Indium Tin Oxide (ITO) or Indium zinc Oxide (Indium Zinc Oxide, IZO) material having a higher work function is added to the anode 131, for example, a layer of ITO or IZO material is formed on the anode 131 to increase the work function of the anode 131.
In the case where the cathode 133 is added with an active metal, two aspects are considered, and the first aspect is to consider the light transmittance of the active metal, the transmittance of the metal being related to its lattice structure, which refers to the manner in which metal atoms are arranged in a specific regular manner. When the lattice structure of the metal is sufficiently compact and there is insufficient space for photons to pass through, the metal exhibits an opaque character. If the thickness of the metal is reduced to some extent, photons may pass through the lattice structure of the metal, causing the metal to become transparent. In another scheme, the work function is required to be considered, the thickness is required to be set in consideration of the light transmittance, and the work function is also required to be considered, and the thickness has an influence on the work function. In general, the cathode 133 is formed using an active metal material, for example, magnesium or silver, and the thickness of the cathode 133 needs to be smaller than that of the reflective metal layer in the anode 131 to achieve high luminous efficiency. However, when the active metal material used for the cathode 133 is thin, for example, 100 to 300 a, oxidation is likely to occur in the deposition and etching steps in the process, and particularly, in the etching process, photoresist residues, etching problems and the like also exist, which affect the work function of the cathode 133, thereby resulting in lower light-emitting efficiency of the inverted bottom-emission display panel 100.
Therefore, when the thickness of the bottom electrode, i.e., the cathode 133, is greater than or equal to 100 a/m and less than or equal to 300 a/m, the cathode 133 can form a plurality of independent cathodes 133, which are not communicated with each other, without etching, by the partition effect of the partition structure 140, so that the cathodes 133 of the adjacent light emitting units 130 are completely separated. Even if a partial cathode redundancy 135 is formed in the partition structure 140, the partial cathode redundancy 135 can be disconnected from the cathode 133 to prevent a problem of current crosstalk. The cathode 133 formed by the active metal material in the present embodiment can reduce the work function of the cathode 133, so as to improve the phenomenon that the hole injection and the electron injection in the inverted organic light emitting display panel 100 are not balanced, and solve the problem that the current inverted organic light emitting display panel 100 has lower light emitting efficiency.
Specifically, the anode 131 is formed by depositing a reflective metal material on the whole surface, the anode 131 is shared by a plurality of light emitting units 130, and in order to match the work functions of the cathode 133 and the light emitting functional layer 132, the anode 131 of this embodiment may be formed by sputtering to form a thin layer of indium tin oxide material, the thickness of which is about 0.01mm to 0.1mm, and then vacuum evaporating a reflective metal material with high reflectivity, which may be generally a silver material, and the thickness of the reflective metal material of the anode 131 is far thicker than that of the active metal material in the cathode 133.
Of course, the solution of the present application may be applied to the top-emission display panel 100, and for the top-emission display panel 100, the bottom electrode of the display panel 100 is formed by using the reflective electrode, and the vapor deposition may be performed by the partition structure 140 of the present application, so that an etching process is not required. For example, the bottom electrode is formed by using an opaque high reflective electrode, the top electrode is formed by using a transparent electrode, the bottom electrode is the anode 131, the top electrode is the cathode 133, and the patterned bottom electrode is directly formed by the partition structure 140, without forming the bottom electrode before the pixel defining layer 120 is formed.
Fig. 5 is a schematic cross-sectional view of a second display panel according to the present application, and referring to fig. 5, the inverted bottom light-emitting display panel 100 according to the present embodiment further includes a cathode auxiliary electrode 134, wherein the cathode auxiliary electrode 134 is formed of a transparent metal oxide material, the cathode auxiliary electrode 134 is disposed under the cathode 133 and is electrically connected to the cathode 133, and the cathode auxiliary electrodes 134 of two adjacent light-emitting units 130 are separated by the pixel defining layer 120.
In order to further improve the light emitting efficiency of the light emitting unit 130 of the inverted bottom light emitting display panel 100, the present embodiment further provides a cathode auxiliary electrode 134 under the cathode 133, and the light transmitting metal oxide material of the cathode auxiliary electrode 134 includes one or both of Indium Tin Oxide (ITO) material or Indium Zinc Oxide (IZO) material, which has a light transmittance of more than 90%. The cathode auxiliary electrode 134 is connected to the pixel active switch in the driving circuit layer 150 through a via hole. It is understood that a driving circuit layer 150 is further disposed on the substrate 110, and the driving circuit layer 150 generally includes a pixel driving circuit of the light emitting unit 130, such as a pixel active switch (thin film transistor), a data driving line, a scan control line, etc., and the cathode 133 of each light emitting unit 130 is connected to the pixel active switch through the cathode auxiliary electrode 134, and the voltage of the cathode 133 is controlled through the pixel active switch.
Specifically, the cathode auxiliary electrodes 134 of two adjacent light emitting units 130 are separated by the pixel defining layer 120, after the process of the pixel driving layer is completed, a via hole needs to be disposed at the output end of the pixel active switch, after the via hole is completed, the cathode auxiliary electrodes 134 are coated, then the cathode auxiliary electrodes 134 are patterned, after the cathode auxiliary electrodes 134 in the plurality of opening areas 101 are reserved, the pixel defining layer 120 is formed, the pixel defining layer 120 covers part of the cathode auxiliary electrodes 134, and a plurality of openings are formed, and the positions of the openings are the opening areas 101. After the partition structure 140 is formed on the pixel defining layer 120, the cathode 133 and the light emitting functional layer 132 are partitioned by the partition structure 140. In this embodiment, by providing the cathode auxiliary electrode 134, the problem of unstable connection performance caused by the need of connecting the cathode 133 using an active metal to the thin film pixel active switch is avoided.
It should be noted that, the cathode auxiliary electrodes 134 of two adjacent light emitting units 130 are separated by the pixel defining layer 120, and the cathode auxiliary electrodes 134 of two adjacent light emitting units 130 are also required to be disposed at intervals to avoid the problem of electrical crosstalk, considering that the cathode auxiliary electrodes 134 need to be directly connected to the cathodes 133 of the respective light emitting units 130. When the barrier layer is formed of a metal material, the barrier layer is in direct contact with the cathode auxiliary electrode 134, and thus it is also necessary to provide a barrier layer between adjacent light emitting units 130.
Specifically, the cathode 133 further includes a cathode 133 redundant electrode, the cathode 133 redundant electrode is disposed on the partition structure 140, and the cathode 133 redundant electrode are disconnected through the partition structure 140. The cathode 133 redundant electrode is mainly the cathode 133 redundant electrode formed by vapor deposition on the pixel defining layer 120 during the whole process of forming the cathode 133, and the cathode 133 redundant electrode may be removed in the subsequent process, or may not be removed.
In order to avoid the electrical connection between the cathode 133 and the redundant electrode of the cathode 133, it is also necessary to define the thickness of the partition structure 140 such that the thickness h of the partition structure 140 is at least 0.01um or more. Of course, the thickness of the partition structure 140 is also related to the thickness of the cathode 133, and the thickness of the cathode 133 may be generally 100 to 300 μm (0.01 to 0.03 μm), in order to meet the above-mentioned requirements of light transmittance and work function, in which case the thickness h of the partition structure 140 should be 0.01 μm or more and 0.06 μm or less. The main consideration of this embodiment is that when the partition structure 140 is used only to partition the cathode 133, the thickness h of the partition structure 140 does not need to exceed 0.06um. Specifically, the thickness of the partition structure 140 is 0.02um or more and 0.05um or less, which has a good effect on the partition cathode 133.
In another embodiment, the blocking structure 140 is further configured to sequentially block one or more of the electron injection layer 1324, the electron transport layer 1321, the hollow blocking layer, the light emitting layer 1322, the electron blocking layer 1326, the hole transport layer 1323, and the hole injection layer 1327 between the open region 101 and the non-open region 102 when the light emitting functional layer 132 is deposited over. However, in consideration of the multi-layered partition, the required thickness of the partition structure 140 is thick, resulting in instability in forming the partition structure 140 using a negative organic gel material. Accordingly, further, the crosstalk problem between the respective light emitting units 130 can be reduced in consideration of the interruption of the electron transport layer 1321 in the light emitting functional layer 132. The thickness of the blocking structure 140 may be controlled such that the blocking structure 140 may block the cathode 133, the electron injection layer 1324, and the electron transport layer 1321. Wherein, the thickness h of the partition structure 140 is greater than or equal to 0.02um and less than or equal to 0.15um. Specifically, when the thickness h of the partition structure 140 is 0.04um or more and 0.1um or less, the partition effect on the cathode 133, the electron injection layer 1324, and the electron transport layer 1321 is good. It should be noted that the anode 131 in the present embodiment needs to use a full-area deposition process to form the full-area anode 131, and when the thickness of the partition structure 140 is larger, the anode 131 is also blocked, so that the thickness of the partition structure 140 is not too large, i.e. 0.15um or less. Of course, the thicker the partition structure 140, the stronger its partition ability, so that the thicker film layer can be partitioned, and when the anode 131 is also partitioned, the thickness of the anode 131 can be increased, so that part of the anode 131 is partitioned, but the anode 131 is not completely partitioned due to the sufficient thickness of the anode 131.
Fig. 6 is a schematic step diagram of a method for manufacturing a display panel according to the present application, fig. 7 is a schematic step diagram of a process for manufacturing a display panel according to the present application, and referring to fig. 6 to 7, the present application also discloses a method for manufacturing a display panel, including the steps of:
S110, providing a substrate base plate;
s120, forming a pixel definition layer on the substrate base plate, and patterning the pixel definition layer to form a plurality of opening areas;
s130, forming a partition structure on the pixel definition layer;
s140, depositing a bottom electrode material on the whole surface, wherein the partition structure is used for partitioning the bottom electrodes of two adjacent light-emitting units;
s150, sequentially forming a light-emitting functional layer and a top electrode in the opening area to form a plurality of light-emitting units;
wherein the partition structure 140 is formed of a negative organic gel material, and the radial width of the partition structure 140 gradually decreases from the direction in which the partition structure 140 approaches the substrate 110.
The partition structure 140 is formed by adopting the negative organic adhesive material, firstly, the partition structure 140 with the upper width and the lower narrow part can be formed by utilizing the negative organic adhesive material in the exposure and development process, and secondly, the partition structure 140 can play an insulating role to prevent the problem of electrical crosstalk between the bottom electrodes of the adjacent light emitting units 130 by utilizing the negative organic adhesive material with stronger insulating property even if the bottom electrode is contacted with the partition structure 140 under the condition that the angle is not controlled in the whole deposition process of the bottom electrode. In the present application, the partition structure 140 is provided, so that the bottom electrodes of the plurality of light emitting units 130 are not connected to each other by the partition structure 140 when the bottom electrodes of the light emitting units 130 are formed. In the process of forming the bottom electrode, the redundant bottom electrode material is not required to be removed through an etching process, and the next process of the light-emitting functional layer 132 can be directly carried out after the bottom electrode is deposited on the whole surface, so that the influence of the etching process on the bottom electrode is reduced. Particularly, when the bottom electrode includes the active metal material, the problems of oxidation, residue and the like of the active metal in the etching process are avoided, the interface of the film layer between the bottom electrode and the light emitting functional layer 132 is improved, the light emitting efficiency of the light emitting unit 130 is improved, and the display effect of the display panel 100 is improved.
In the present embodiment, the inverted bottom-emission display panel 100 is taken as an example for illustration, but the manufacturing method of the display panel 100 provided by the present application is not limited to manufacturing the inverted bottom-emission display panel 100, and the manufacturing method of the above-mentioned embodiment is also applicable to the front-emission display panel 100. Specifically, the top electrode is an anode 131, the bottom electrode is a cathode 133, the light-emitting functional layer 132 comprises an electron transport layer 1321, a light-emitting layer 1322 and a hole transport layer 1323, the electron transport layer 1321 is arranged on the cathode 133, the light-emitting layer 1322 is arranged on the electron transport layer 1321, the hole transport layer 1323 is arranged on the light-emitting layer 1322, the anode 131 is arranged on the hole transport layer 1323, the cathode 133 is formed by one or two of a magnesium material and a silver material, the cathode 133 is a light-transmitting electrode, the anode 131 is formed by a reflective metal material, the anode 131 is shared by a plurality of light-emitting units 130, and the light emitted by the light-emitting units 130 is emitted from one side of the substrate base plate 110.
The step S120 is preceded by a step of forming a driving circuit layer 150 on the substrate base 110, the driving circuit layer 150 including a plurality of thin film transistors and driving lines, the thin film transistors and the driving lines forming a driving circuit for driving the plurality of light emitting units 130 to emit light. In the process of forming the driving circuit layer 150, a via hole is further provided corresponding to the thin film transistor driving the light emitting unit 130, and the via hole is used to provide the cathode auxiliary electrode 134 connected between the thin film transistor and the cathode 133 of the light emitting unit 130.
The step of S120 further includes the steps of:
s121, depositing cathode auxiliary electrode materials on the substrate, patterning and forming a cathode auxiliary electrode in the opening area;
And S122, depositing and patterning the cathode auxiliary electrodes to form pixel definition layers, separating the cathode auxiliary electrodes of two adjacent light emitting units through the pixel definition layers, and forming a plurality of opening areas, wherein the cathode auxiliary electrodes are exposed from the opening areas.
In this embodiment, after the above-mentioned process of the driving circuit layer 150 is completed, the cathode auxiliary electrode 134 is formed in the opening area 101, and the cathode auxiliary electrode 134 is connected to the output terminal of the thin film transistor at the via hole of the driving circuit layer 150, so as to realize the voltage control of the cathode 133.
In one embodiment, the step of S150 includes:
S151, depositing the luminescent functional layer material on the whole surface, and isolating luminescent functional layers of two adjacent luminescent units through an isolating structure;
and S152, depositing anodes on the whole surface to form a plurality of light emitting units.
In this embodiment, the light emitting functional layer 132 of the light emitting unit 130 is formed by the partition structure 140, and the light emitting functional layer 132 may include an electron injection layer 1324, an electron transport layer 1321, a hole blocking layer 1325, a light emitting layer 1322, an electron blocking layer 1326, a hole transport layer 1323, and a hole injection layer 1327 sequentially disposed from the cathode 133 toward the anode 131. In the present embodiment, the anode 131 may be formed entirely by providing the thickness of the partition structure 140 such that the partition structure 140 cannot partition the anode 131.
The partition structure 140 is formed by adopting the negative organic adhesive material, firstly, the partition structure 140 with the upper width and the lower narrow part can be formed by utilizing the negative organic adhesive material in the exposure and development process, and secondly, the partition structure 140 can play an insulating role to prevent the problem of electrical crosstalk between the bottom electrodes of the adjacent light emitting units 130 by utilizing the negative organic adhesive material with stronger insulating property even if the bottom electrode is contacted with the partition structure 140 under the condition that the angle is not controlled in the whole deposition process of the bottom electrode. In the present application, the partition structure 140 is provided, so that the bottom electrodes of the plurality of light emitting units 130 are not connected to each other by the partition structure 140 when the bottom electrodes of the light emitting units 130 are formed. In the process of forming the bottom electrode, the redundant bottom electrode material is not required to be removed through an etching process, and the next process of the light-emitting functional layer 132 can be directly carried out after the bottom electrode is deposited on the whole surface, so that the influence of the etching process on the bottom electrode is reduced. Particularly, when the bottom electrode includes the active metal material, the problems of oxidation, residue and the like of the active metal in the etching process are avoided, the interface of the film layer between the bottom electrode and the light emitting functional layer 132 is improved, the light emitting efficiency of the light emitting unit 130 is improved, and the display effect of the display panel 100 is improved.
It should be noted that, the inventive concept of the present application can form a very large number of embodiments, but the application documents are limited in space and cannot be listed one by one, so that on the premise of no conflict, the above-described embodiments or technical features can be arbitrarily combined to form new embodiments, and after the embodiments or technical features are combined, the original technical effects will be enhanced.
The above description of the application in connection with specific alternative embodiments is further detailed and it is not intended that the application be limited to the specific embodiments disclosed. It will be apparent to those skilled in the art that several simple deductions or substitutions may be made without departing from the spirit of the application, and these should be considered to be within the scope of the application.

Claims (7)

1.一种显示面板的制作方法,其特征在于,包括步骤:1. A method for manufacturing a display panel, characterized by comprising the following steps: 提供一衬底基板;Provide a substrate; 在所述衬底基板上形成像素定义层,并图案化所述像素定义层形成多个开口区,包括:在所述衬底基板上沉积阴极辅助电极材料,图案化后在所述开口区形成阴极辅助电极;在所述阴极辅助电极上沉积并图案化形成像素定义层,相邻两个发光单元的阴极辅助电极通过所述像素定义层隔开,并形成多个开口区,所述阴极辅助电极从所述开口区裸露;Forming a pixel definition layer on the substrate and patterning the pixel definition layer to form multiple opening regions includes: depositing a cathode auxiliary electrode material on the substrate and forming a cathode auxiliary electrode in the opening region after patterning; depositing and patterning a pixel definition layer on the cathode auxiliary electrode, wherein the cathode auxiliary electrodes of two adjacent light-emitting units are separated by the pixel definition layer and multiple opening regions are formed, and the cathode auxiliary electrode is exposed from the opening region. 在所述像素定义层上形成隔断结构;A partition structure is formed on the pixel definition layer; 整面沉积底电极材料,所述隔断结构用于隔断相邻两个发光单元的底电极;The bottom electrode material is deposited over the entire surface, and the partition structure is used to isolate the bottom electrodes of two adjacent light-emitting units; 在所述开口区依次形成发光功能层、顶电极以形成多个发光单元,包括:整面沉积发光功能层材料,通过悬垂结构隔断相邻两个所述发光单元的发光功能层;整面沉积阳极,以形成多个所述发光单元;A light-emitting functional layer and a top electrode are sequentially formed in the opening area to form multiple light-emitting units, including: depositing light-emitting functional layer material over the entire surface, separating the light-emitting functional layers of two adjacent light-emitting units by a hanging structure; and depositing an anode over the entire surface to form multiple light-emitting units. 其中,所述顶电极为阳极,所述底电极为阴极;所述阴极为透光电极;所述阳极采用反射金属材料形成,多个所述发光单元共用所述阳极;所述发光单元的出光从所述衬底基板的一侧发出;The top electrode is the anode, and the bottom electrode is the cathode; the cathode is a light-transmitting electrode; the anode is formed of a reflective metal material, and multiple light-emitting units share the anode; the light emitted by the light-emitting unit is emitted from one side of the substrate. 其中,所述隔断结构采用负性有机胶材料形成,从隔断结构靠近所述衬底基板的方向上,所述隔断结构的径向宽度逐渐降低;The partition structure is formed using a negative organic adhesive material, and the radial width of the partition structure gradually decreases from the direction of the partition structure approaching the substrate. 所述阴极辅助电极设置在所述阴极下,且与所述阴极电性连接。The cathode auxiliary electrode is disposed below the cathode and is electrically connected to the cathode. 2.根据权利要求1所述的显示面板的制作方法,其特征在于,所述隔断结构环绕所述开口区设置,所述隔断结构的截面形状为倒梯形;2. The method for manufacturing a display panel according to claim 1, wherein the partition structure is arranged around the opening area, and the cross-sectional shape of the partition structure is an inverted trapezoid; 所述隔断结构远离所述衬底基板的一侧为顶面,所述隔断结构靠近所述衬底基板的一侧为底面,所述隔断结构的顶面与所述隔断结构的侧面的夹角在30度至70度之间,或所述隔断结构的侧面与所述像素定义层的顶面的夹角在30度至70度之间。The side of the partition structure away from the substrate is the top surface, and the side of the partition structure close to the substrate is the bottom surface. The angle between the top surface of the partition structure and the side surface of the partition structure is between 30 degrees and 70 degrees, or the angle between the side surface of the partition structure and the top surface of the pixel definition layer is between 30 degrees and 70 degrees. 3.根据权利要求2所述的显示面板的制作方法,其特征在于,所述隔断结构的厚度大于等于0.01um小于等于0.06um;3. The method for manufacturing a display panel according to claim 2, wherein the thickness of the partition structure is greater than or equal to 0.01 μm and less than or equal to 0.06 μm; 在非开口区位置处,所述隔断结构的径向宽度小于等于所述像素定义层的径向宽度;At non-opening locations, the radial width of the partition structure is less than or equal to the radial width of the pixel definition layer; 所述负性有机胶材料包括聚酰亚胺材料、环氧树脂材料或聚酸酯材料。The negative organic adhesive material includes polyimide material, epoxy resin material or polyester material. 4.根据权利要求3所述的显示面板的制作方法,其特征在于,所述底电极厚度大于等于0.01um小于等于0.03um,所述隔断结构的厚度大于等于0.02um小于等于0.05um;4. The method for manufacturing a display panel according to claim 3, wherein the thickness of the bottom electrode is greater than or equal to 0.01 μm and less than or equal to 0.03 μm, and the thickness of the partition structure is greater than or equal to 0.02 μm and less than or equal to 0.05 μm; 在所述隔断结构中,所述顶面与所述侧面的夹角在45度至60度之间。In the partition structure, the angle between the top surface and the side surface is between 45 degrees and 60 degrees. 5.根据权利要求1所述的显示面板的制作方法,其特征在于,所述阴极采用镁材料和银材料中的一种或两种形成;5. The method for manufacturing a display panel according to claim 1, wherein the cathode is formed using one or both of magnesium and silver materials; 所述发光功能层包括电子传输层、发光层和空穴传输层,所述电子传输层设置在所述阴极上,所述发光层设置在所述电子传输层上,所述空穴传输层设置在所述发光层上,所述阳极设置在所述空穴传输层上。The light-emitting functional layer includes an electron transport layer, a light-emitting layer, and a hole transport layer. The electron transport layer is disposed on the cathode, the light-emitting layer is disposed on the electron transport layer, the hole transport layer is disposed on the light-emitting layer, and the anode is disposed on the hole transport layer. 6.根据权利要求5所述的显示面板的制作方法,其特征在于,所述阴极辅助电极采用透明金属氧化物材料形成。6. The method for manufacturing a display panel according to claim 5, wherein the cathode auxiliary electrode is formed of a transparent metal oxide material. 7.根据权利要求5所述的显示面板的制作方法,其特征在于,所述阴极还包括阴极冗余电极,所述阴极冗余电极设置在所述隔断结构上,所述阴极和所述阴极冗余电极之间通过所述隔断结构断开;7. The method for manufacturing a display panel according to claim 5, wherein the cathode further includes a redundant cathode electrode, the redundant cathode electrode is disposed on the partition structure, and the cathode and the redundant cathode electrode are disconnected through the partition structure; 所述隔断结构还用于在电子传输层、发光层和空穴传输层整面沉积时,依次隔断开口区与非开口区之间的电子传输层、发光层和空穴传输层。The isolation structure is also used to sequentially isolate the electron transport layer, the light-emitting layer, and the hole transport layer between the opening region and the non-opening region during the full-surface deposition of the electron transport layer, the light-emitting layer, and the hole transport layer.
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