WO2023116172A1 - Light-emitting diode and manufacturing method therefor - Google Patents

Abstract

The present application discloses a light-emitting diode and a manufacturing method therefor. The light-emitting diode comprises: an interdigitated electrode, a dimple or bump being formed on the surface of the interdigitated electrode; a functional layer, the thickness of the functional layer being less than the depth of the dimple or the height of the bump; and a light-emitting layer. In this way, the problem of small effective contact area between a functional layer and a light-emitting layer in a back-contact device structure can be alleviated, restriction on the injection amount of carriers from the functional layer to the light-emitting layer by the back-contact device structure is reduced, and the device efficiency is improved.

Description

Light-emitting diode and its preparation method

This application claims priority to a Chinese patent application with application number 202111589053.8 and application title "Light Emitting Diode and Method for Making It" filed at the China Patent Office on December 23, 2021, the entire contents of which are hereby incorporated by reference into this application middle.

technical field

The present application relates to the field of display technology, in particular to a light emitting diode and a preparation method thereof.

Background technique

Light-emitting diodes (light-emitting diodes, LEDs) are commonly used light-emitting devices, which release energy and emit light through the recombination of electrons and holes. Because they can efficiently convert electrical energy into light energy, they are widely used in many fields of modern society. , such as lighting, flat panel display, and medical device fields.

At present, light-emitting diodes have a variety of device configurations. According to different division methods, light-emitting diodes can be divided into top emitter devices, bottom emitter devices, double-sided emitter devices, rigid devices, flexible devices, and Divided into positive structure devices, inverted structure devices, and can also be divided into stacked devices and back contact devices. Among them, the back-contact device is formed by photolithography on the electrode in advance and deposited in a physical or chemical way to form interdigitated electrodes, and then deposits functional layer materials and light-emitting layer materials on the interdigitated electrodes to complete the preparation of the device. Compared with the stacked device, the back-contact device can avoid the damage to the light-emitting layer during the deposition of the functional layer during the manufacturing process, and the structure of the back-contact device can also prevent the functional layer from blocking the light-emitting layer, reducing the light-emitting layer. The amount of light output, resulting in adverse effects on device performance.

However, based on the device structure of the back-contact device, under the same light-emitting area, the contact area between the functional layer and the light-emitting layer will be reduced by 40~60% compared with the contact area between the functional layer and the light-emitting layer in the stacked device, and the reduction The effective contact area will affect the injection of carriers from the functional layer to the light-emitting layer, reducing the luminous efficiency of the device.

technical problem

Therefore, the problem of the small effective contact area between the functional layer and the light-emitting layer in the back-contact device structure needs to be improved, the restriction on the injection amount of carriers from the functional layer to the light-emitting layer in the back-contact device structure needs to be reduced, and the device efficiency needs to be improved. .

technical solution

Therefore, the present application provides a light emitting diode and a preparation method thereof.

An embodiment of the present application provides a light emitting diode, including:

Interdigital electrodes, the surface of the interdigital electrodes is formed with pits or protrusions;

a functional layer, the functional layer is formed on the surface of the interdigital electrode, and the thickness of the functional layer is smaller than the depth of the pit or the height of the protrusion; and

A light emitting layer, the light emitting layer is formed on the surface of the functional layer.

Optionally, in some embodiments of the present application, the depth of the pits or the height of the protrusions is 11-70 nm.

Optionally, in some embodiments of the present application, the depth of the pits or the height of the protrusions is 15-50 nm.

Optionally, in some embodiments of the present application, the functional layer is selected from one or more of a charge injection layer, a charge transport layer, and a charge blocking layer.

Optionally, in some embodiments of the present application, the interdigitated electrodes include a first electrode and a second electrode forming an interdigitated structure, and pits are formed on the surfaces of the first electrode and the second electrode or raised;

The functional layer includes a first functional layer and a second functional layer, the first functional layer is formed on the surface of the first electrode, the second functional layer is formed on the surface of the second electrode, and the first functional layer is formed on the surface of the second electrode. Both the thicknesses of the first functional layer and the second functional layer are smaller than the depth of the pit or the height of the protrusion;

The luminescent layer is formed on the surfaces of the first functional layer and the second functional layer, and covers a space area between the first functional layer and the second functional layer.

Optionally, in some embodiments of the present application, the interdigitated electrodes include a first electrode and a second electrode forming an interdigitated structure, the first electrode is a cathode, and the material of the cathode is selected from zinc, tin One or more of , titanium, aluminum, ITO, FTO.

Optionally, in some embodiments of the present application, the interdigitated electrodes include a first electrode and a second electrode forming an interdigitated structure, the second electrode is an anode, and the material of the anode is selected from copper, nickel , aluminum, chromium, platinum, ITO, FTO in one or more.

Optionally, in some embodiments of the present application, the light emitting layer is a quantum dot light emitting layer, and the material of the quantum dot light emitting layer is selected from CdSe, CdS, ZnSe, ZnS, CdTe, ZnTe, CdZnS, CdZnSe, CdZnTe , ZnSeS, ZnSeTe, ZnTeS, CdSeS, CdSeTe, CdTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdSeSTe, ZnSeSTe, InP, GaP, GaAs, InAs, InAsP, GaAsP, InGaP, InGaAs, PbS, PbSe, PbTe, PbSeS, PbSeTe, CdZnSe /ZnS, CdZnSeS/ZnS, CdTe/ZnS, CdZnSe/ZnS, CdZnSeS/ZnS, CdTe/ZnS, CdTe/CdSe, CdTe/ZnTe, CdSe/CdS, CdSe/ZnS, InP/ZnS, inorganic perovskite semiconductors, One or more of organic-inorganic hybrid perovskite semiconductors; wherein, the general formula of the inorganic perovskite semiconductor is AMX ₃ , wherein A is Cs ⁺ , and M is selected from Pb ²⁺ , Sn ²⁺ , Cu ²⁺ , Ni ²⁺ , Cd ²⁺ , Cr ²⁺ , Mn ²⁺ , Co ²⁺ , Fe ²⁺ , Ge ²⁺ , Yb ²⁺ , Eu ²⁺ , X is selected from One of Cl ^- , Br ^- , I ^- ; the general formula of the organic-inorganic hybrid perovskite semiconductor is BMX ₃ , wherein B is an organic amine cation, and M is selected from Pb ²⁺ , Sn ^{2 +} , Cu ²⁺ , Ni ²⁺ , Cd ²⁺ , Cr ²⁺ , Mn ²⁺ , Co ²⁺ , Fe ²⁺ , Ge ²⁺ , Yb ²⁺ , Eu ²⁺ , X is selected from One of Cl ^- , Br ^- , I ^- .

Optionally, in some embodiments of the present application, the material of the protrusion is the same as that of the interdigital electrode.

Correspondingly, the embodiment of the present application also provides a method for manufacturing a light-emitting diode, including the following steps:

providing a substrate, an electrode material, a pit material for forming pits, and an etching solution for etching the pit material;

Formation of interdigitated electrodes: depositing the electrode material and the pit material on the substrate at the same time to form a doped structure layer with an interdigitated structure; using the etching solution to etch the doped structure layer The pit material forms an interdigitated electrode having pits;

Forming a functional layer: forming a functional layer on the interdigital electrodes, the thickness of the functional layer being smaller than the depth of the pit; and

Light-emitting layer formation: a light-emitting layer is deposited on the functional layer.

Optionally, in some embodiments of the present application, the mass ratio of the electrode material to the pit material is 0.1-10:1.

Optionally, in some embodiments of the present application, the interdigital electrodes include a first electrode and a second electrode, and the functional layer includes a first functional layer and a second functional layer;

The formation of the interdigitated electrodes and the formation of the functional layer include the formation of the first electrode, the formation of the first functional layer, the formation of the second electrode and the formation of the second functional layer, and the steps include:

Depositing the material of the first electrode and the material of the pit simultaneously on the substrate to form a first doped structure layer corresponding to the first electrode in the interdigitated structure; using the etching solution to etch etching the pit material in the first doped structure layer to form a first electrode with pits;

forming a first functional layer on the first electrode, the thickness of the first functional layer is smaller than the depth of the pit;

shielding the first functional layer, depositing the material of the second electrode and the material of the pit on the substrate at the same time, forming a second doped structure layer corresponding to the second electrode in the interdigitated structure ; using the etchant to etch the pit material in the second doped structure layer to form a second electrode with pits;

A second functional layer is formed on the second electrode, and the thickness of the second functional layer is smaller than the depth of the pit.

Optionally, in some embodiments of the present application, in the formation of the functional layer, the formation of the functional layer on the interdigital electrode is realized by oxidizing the interdigital electrode.

Optionally, in some embodiments of the present application, the thickness of the functional layer is 9-30 nm.

Optionally, in some embodiments of the present application, the electrode material is selected from one or more of conductive metals and conductive metal oxides; wherein the conductive metal is selected from zinc, tin, copper, chromium, One or more of platinum, nickel, titanium, aluminum, the conductive metal oxide is selected from one or more of ITO, FTO; the pit material is selected from gold, aluminum, copper, palladium One or more; the etching solution is selected from the product models are AU One or more of etch 200, CR etch 200/210, CU etch 200 UBM, TechniEtchTMTC, TechniEtch Al80.

Correspondingly, the embodiment of the present application also provides a method for manufacturing a light-emitting diode, which includes the following steps:

providing substrate, electrode material and bump material for bump formation;

Forming interdigitated electrodes: depositing the electrode material on the substrate to form a basic electrode with an interdigitated structure; depositing the raised material on the surface of the basic electrode to form a raised interdigitated electrode;

Forming a functional layer: forming a functional layer on the interdigital electrodes, the thickness of the functional layer being smaller than the height of the protrusion; and

Light-emitting layer formation: a light-emitting layer is deposited on the functional layer.

Optionally, in some embodiments of the present application, the interdigital electrodes include a plurality of electrode units forming an interdigital structure, and the protrusions are formed on each of the electrode units.

Optionally, in some embodiments of the present application, the interdigitated electrode includes a plurality of electrode units forming an interdigital structure, each of the electrode units is formed with the protrusion, each of the protrusions The heights are all smaller than the spacing between the adjacent electrode units.

Optionally, in some embodiments of the present application, the mass ratio of the electrode material to the protrusion material is 100:0.1-5.

Optionally, in some embodiments of the present application, the protrusion material is the same as the electrode material, and the electrode material is selected from one or more of conductive metals and conductive metal oxides; wherein, the The conductive metal is selected from one or more of zinc, tin, copper, chromium, platinum, nickel, titanium, and aluminum, and the conductive metal oxide is selected from one or more of ITO and FTO.

Beneficial effect

The present application increases the specific surface area through the pits or protrusions on the surface of the interdigitated electrodes, and at the same time makes the thickness of the functional layer formed on the surface of the interdigitated electrodes smaller than the depth of the pits or the height of the protrusions, so as to maintain the increased In this way, after the light-emitting layer is formed on the surface of the functional layer, the effective contact area between the functional layer and the light-emitting layer increases, and the injection amount of carriers from the functional layer to the light-emitting layer is improved, thereby improving the performance of the device. .

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can also be obtained based on these drawings without any creative effort.

Fig. 1 is the flow chart of the preparation method of the light-emitting diode provided by the embodiment of the present application;

Fig. 2 is a flow chart of the preparation method of the light-emitting diode provided by the embodiment of the present application;

FIG. 3 is a schematic diagram of a doped structure layer provided in Embodiment 1 of the present application;

FIG. 4 is a schematic structural diagram of an interdigitated electrode with pits provided in Embodiment 1 of the present application;

FIG. 5 is a schematic structural view of the functional layer formed on the surface of the interdigital electrode provided by Embodiment 1 of the present application;

FIG. 6 is a schematic structural diagram of a light emitting diode provided in Embodiment 1 of the present application;

FIG. 7 is a schematic diagram of the first doped structure layer provided in Embodiment 2 of the present application;

FIG. 8 is a schematic structural diagram of the first electrode provided in Embodiment 2 of the present application;

Fig. 9 is a schematic structural view of the first functional layer formed on the surface of the first electrode and the second functional layer formed on the surface of the second electrode provided by Embodiment 2 of the present application;

Fig. 10 is a schematic structural diagram of a light emitting diode provided in Embodiment 2 of the present application;

Figure 11 is a comparison chart of blue QLED device performance (voltage-brightness) data;

Figure 12 is a comparison chart of blue QLED device performance (luminance-external quantum efficiency) data.

Among them, the reference signs are summarized as follows:

Interdigital electrode 101; Pit 102; Functional layer 103; Light emitting layer 104;

The first electrode 201 ; the second electrode 202 ; the first functional layer 203 ; the second functional layer 204 .

Embodiment of this application

The following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Apparently, the described embodiments are only some of the embodiments of the application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of this application.

Embodiments of the present application provide a light emitting diode and a manufacturing method thereof. Each will be described in detail below. It should be noted that the description sequence of the following embodiments is not intended to limit the preferred sequence of the embodiments. In addition, in the description of the present application, the term "including" means "including but not limited to".

In this application, expressions such as "one or more" refer to one or more of the listed items, and "multiple" refers to any combination of two or more of these items, including single items (species) ) or any combination of plural items (species), for example, “at least one (species) of a, b, or c” or “at least one (species) of a, b, and c” can mean: a ,b,c,a-b (that is, a and b),a-c,b-c, or a-b-c, where a,b,c can be single or multiple.

Various embodiments of the present application may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be construed as a rigid limitation on the scope of the application; therefore, the described range should be regarded as The description has specifically disclosed all possible subranges as well as individual values within that range. For example, a description of a range from 1 to 6 should be considered to have specifically disclosed subranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and Single numbers within the stated ranges, eg 1, 2, 3, 4, 5 and 6, apply regardless of the range. Additionally, whenever a numerical range is indicated herein, it is meant to include any cited numeral (fractional or integral) within the indicated range.

In the first aspect, an embodiment of the present application provides a light emitting diode, including:

Interdigitated electrodes, pits or protrusions are formed on the surface of the interdigitated electrodes;

a functional layer, the functional layer is formed on the surface of the interdigitated electrode, and the thickness of the functional layer is smaller than the depth of the pit or the height of the protrusion; and

The light emitting layer is formed on the surface of the functional layer.

Interdigitated electrode, that is, an electrode with an interdigitated structure. The interdigitated structure is a structure with a periodic pattern in a finger-like or comb-shaped plane. The aforementioned structure can be called an interdigitated structure. It does not limit whether the pattern is symmetrical or whether the number of periods is the same, nor does it limit other structural parts of the component with the interdigitated structure. In addition, it should be noted that the pits or protrusions only indicate that there is an area to improve the specific surface area of the interdigital electrodes, and are not used as restrictions on the shape or configuration. The pits can be grooves, concave spherical shapes, not Regular structures, etc., the protrusions can be bumps, cones, etc.

The "surface of the interdigitated electrodes" referred to in the LED structure also includes the front and side surfaces of the interdigitated electrodes. The front of the functional layer is the side close to the light-emitting layer, and the front of the light-emitting layer is the side that emits light. No matter on the front or the side, the thickness of the functional layer is smaller than the depth of the pit or the height of the protrusion.

In some embodiments, the depth of the pits or the height of the protrusions is 11-70 nm, preferably 15-50 nm.

In some embodiments, the functional layer is selected from one or more of charge injection layer, charge transport layer, and charge blocking layer. When the functional layer is a single layer, the thickness of the single layer is less than the depth of the pit or the height of the protrusion; when the functional layer is multi-layered, the sum of the thicknesses of the multilayer structure should be less than the depth of the pit or the height of the protrusion.

In some embodiments, the interdigitated electrode includes a first electrode and a second electrode forming an interdigitated structure, and pits or protrusions are formed on the surfaces of the first electrode and the second electrode;

The functional layer includes a first functional layer and a second functional layer, the first functional layer is formed on the surface of the first electrode, the second functional layer is formed on the surface of the second electrode, and the thicknesses of the first functional layer and the second functional layer are less than the depth of the dimples or the height of the protrusions;

The luminous layer is formed on the surfaces of the first functional layer and the second functional layer, and covers the interval area between the first functional layer and the second functional layer.

Further, the first electrode can be a cathode, and the material of the cathode is selected from one or more of zinc, tin, titanium, aluminum, ITO, FTO; correspondingly, the second electrode is an anode, and the material of the anode is selected from copper, One or more of nickel, aluminum, chromium, platinum, ITO, FTO. Certainly, in some embodiments, the first electrode may also be an anode, and the second electrode may be a cathode accordingly.

The light emitting diode provided by the present invention can be of different types, such as a three-layer device, a multilayer device; another example is an organic light emitting diode (Organic Light-Emitting Diode, OLED), Quantum Dot Light-Emitting Diode (Quantum Dot Light Emitting Diodes, QLED). This solution is especially suitable for QLEDs. For QLEDs with this structure, the quantum dot light-emitting layer is formed on the surface of the functional layer, so it can avoid damage to the quantum dot light-emitting layer when the functional layer material is deposited, and at the same time prevent the functional layer from affecting the quantum dots. The shading of dot fluorescence improves the light extraction efficiency of the device, and there is a larger effective contact area between the quantum dot light-emitting layer and the functional layer, thus increasing the injection amount of carriers and improving the overall performance of the device.

When the light-emitting layer is a quantum dot light-emitting layer, the material of the quantum dot light-emitting layer can be selected from CdSe, CdS, ZnSe, ZnS, CdTe, ZnTe, CdZnS, CdZnSe, CdZnTe, ZnSeS, ZnSeTe, ZnTeS, CdSeS, CdSeTe, CdTeS, CdZnSeS , CdZnSeTe, CdZnSTe, CdSeSTe, ZnSeSTe, InP, GaP, GaAs, InAs, InAsP, GaAsP, InGaP, InGaAs, PbS, PbSe, PbTe, PbSeS, PbSeTe, CdZnSe/ZnS, CdZnSeS/ZnS, CdTe/ZnS, CdZnSe/ZnS , CdZnSeS/ZnS, CdTe/ZnS, CdTe/CdSe, CdTe/ZnTe, CdSe/CdS, CdSe/ZnS, InP/ZnS, inorganic perovskite semiconductor, organic-inorganic hybrid perovskite semiconductor or more; wherein, the general formula of the inorganic perovskite semiconductor is AMX ₃ , wherein A is Cs ⁺ , and M is selected from Pb ²⁺ , Sn ²⁺ , Cu ²⁺ , Ni ²⁺ , Cd ²⁺ , Cr ²⁺ , Mn ²⁺ , Co ²⁺ , Fe ²⁺ , Ge ²⁺ , Yb ²⁺ , Eu ²⁺ , X is selected from one of Cl ^- , Br ^- , I ^- ; organic- The general formula of the inorganic hybrid perovskite semiconductor is BMX ₃ , where B is an organic amine cation, and M is selected from Pb ²⁺ , Sn ²⁺ , Cu ²⁺ , Ni ²⁺ , Cd ²⁺ , Cr ²⁺ , One of Mn ²⁺ , Co ²⁺ , Fe ²⁺ , Ge ²⁺ , Yb ²⁺ , Eu ²⁺ , and one of X selected from Cl ^- , Br ^- , I ^- .

In some embodiments, the material of the protrusion is the same as that of the interdigital electrodes. In this way, adverse effects on device performance can be avoided.

In some embodiments, the distance between the electrode units forming the interdigitated structure is 10-1000 nm, and the width of the electrode units may also be 10-1000 nm.

In the second aspect, please refer to FIG. 1, the embodiment of the present invention also provides a method for preparing a light emitting diode, including the following steps:

S301. Formation of interdigitated electrodes: Deposit electrode materials and pit materials on the substrate at the same time to form a doped structure layer with an interdigitated structure; use an etching solution to etch the pit materials in the doped structure layer to form pits The interdigitated electrodes;

S302, forming a functional layer: forming a functional layer on the interdigital electrodes, the thickness of the functional layer is smaller than the depth of the pit; and

S303. Forming a light emitting layer: depositing a light emitting layer on the functional layer.

It should be noted that the above "formation of interdigital electrodes" refers to the formation of interdigital electrodes with pits.

Further, in the step of forming the interdigital electrodes, before depositing the electrode material and the pit material on the substrate at the same time, in order to increase the bonding force between the substrate and the interdigital electrodes, it may be carried out on the substrate. After the single-step photolithography, the photoresist is used as the evaporation mask to evaporate the adsorption layer material; after the adsorption layer is evaporated, the electrode material can be used to evaporate the conductive electrode according to the interdigital structure. The pit material is selected for co-evaporation to form a doped structure layer; then the photoresist is removed by using the etching solution; and the pit material is selectively removed by the etching solution to form an interdigital electrode with pits.

In some embodiments, the material of the above-mentioned adsorption layer may be selected from one or more of titanium and chromium, and the thickness of the adsorption layer may be 5-10 nm.

The interdigitated electrode includes a cathode and an anode. In some embodiments, the thickness of the interdigitated electrode can be 60-500nm. The cathode and the anode can be selected from the same electrode material, and the electrode material can be selected from one of conductive metals and conductive metal oxides. One or more; wherein the conductive metal can be selected from but not limited to zinc, tin, copper, chromium, platinum, nickel, titanium, aluminum, and the conductive metal oxide can be selected from but not limited to ITO, FTO. When the same electrode material is selected for the cathode and anode, the electrode material and the pit material can be co-deposited to form a doped structure layer corresponding to the cathode and anode, and then the pit material is removed using an etching solution.

In some embodiments, the etchant can be selected corresponding to the pit material used, so that the pit material can be etched with the etchant.

In some embodiments, the mass ratio of the electrode material to the pit material is 0.1˜10:1. An appropriate dosage ratio can limit the number of pits formed on the interdigitated electrodes.

In some embodiments, in the steps of forming the functional layer and forming the light-emitting layer, the formation of the layer structure can be achieved by technical means well known in the art, including chemical or physical methods. Among them, the chemical method is, for example, chemical vapor deposition method, continuous ion layer adsorption and reaction method, anodic oxidation method, electrolytic deposition method, and co-precipitation method. The physical method can choose physical coating method or solution processing method. Specifically, the physical coating method is, for example, thermal evaporation coating method, electron beam evaporation coating method, magnetron sputtering method, multi-arc ion coating method, physical vapor deposition method, atomic layer deposition method, pulsed laser deposition method; solution processing method such as Spin coating method, printing method, inkjet printing method, blade coating method, printing method, dipping method, soaking method, spraying method, roller coating method, casting method, slit coating method, strip coating method . For specific processing methods and processing conditions, reference may be made to common methods in the art, and will not be repeated here.

In some embodiments, the functional layer is formed by electrochemical deposition, and the light emitting layer is formed by solution deposition. Since the electrode is an interdigitated electrode with pits, and the thickness of the functional layer formed on the surface of the interdigitated electrodes is smaller than the depth of the pits, when the light-emitting layer is formed by the solution method, the material of the light-emitting layer will fill the functional layer based on the interdigitated electrodes. In this way, the effective contact area between the light-emitting layer and the functional layer is increased, and the carrier injection amount of the device is improved.

In some embodiments, the functional layer is a charge transport layer, and the charge transport layer includes an electron transport layer and a hole transport layer. The material of electron transport layer can be selected from but not limited to ZnO, TiO ₂ , SnO ₂ , Ta ₂ O ₃ , ZrO ₂ , NiO, TiLiO, ZnAlO, ZnMgO, ZnSnO, ZnLiO, InSnO, the material of hole transport layer can be selected from But not limited to _NiOx , PEDOT:PSS, CuSCN, _CuOx .

In some embodiments, the functional layer is formed on the surface of the interdigital electrode by immersing the interdigital electrode with pits in the electrochemical reaction solution, but affected by the structure of the interdigital electrode, the distance between the cathode and the anode of the interdigital electrode The spacing is small, therefore, when a voltage is applied to the cathode or anode of the interdigitated electrode to deposit the charge transport layer, the adjacent unvoltage-applied electrodes will be disturbed and are at the same potential, so that it is easy to cause the deposition of the charge transport layer. A small amount of material is deposited onto adjacent electrode or functional layer surfaces, negatively affecting device performance.

Based on the above reasons, in some embodiments, the interdigital electrodes include a first electrode and a second electrode, and the functional layer includes a first functional layer and a second functional layer;

The formation of the interdigitated electrodes and the formation of the functional layer include the formation of the first electrode, the formation of the first functional layer, the formation of the second electrode and the formation of the second functional layer, and the steps performed include:

Depositing the material of the first electrode and the pit material on the substrate at the same time to form a first doped structure layer corresponding to the first electrode in the interdigitated structure; using an etching solution to etch the pit material in the first doped structure layer , forming a first electrode with pits;

forming a first functional layer on the first electrode, the thickness of the first functional layer is smaller than the depth of the pit;

Blocking the first functional layer, depositing the material of the second electrode and the pit material on the substrate at the same time, forming a second doped structure layer corresponding to the second electrode in the interdigitated structure; etching the second doped structure with an etching solution a dimpled material in the layer forming a second electrode having dimples;

A second functional layer is formed on the second electrode, and the thickness of the second functional layer is smaller than the depth of the pit.

After the preparation of the first electrode and the first functional layer formed on the surface of the first electrode is completed, the deposition of materials of different structural layers is avoided by blocking the first functional layer and continuing to prepare the second electrode and the second functional layer. Interfering with each other, the method can be viewed as a two-step photolithography combined with electrochemical deposition. Further, the first step of photolithography is carried out. First, the first electrode is made, the photoresist is removed, and then the first functional layer is deposited on the first electrode by electrochemical deposition. On this basis, the second step of photolithography is carried out to make the first electrode. For the second electrode, electrochemical deposition is performed without removing the photoresist, and the second functional layer is deposited on the surface of the second electrode. In this case, since the photoresist used in the second photolithography step covers the first functional layer (because the first functional layer is formed on the surface of the first electrode, the first electrode is also indirectly covered by the mask), therefore, the second Both the first electrode and the first functional layer are blocked, thus avoiding the adverse effect of the material of the second functional layer on the first functional layer, thereby improving the performance of the device.

The above-mentioned first electrode may be a cathode or an anode, and the corresponding second electrode may be an anode or a cathode. When the functional layer is a charge transport layer, in the preparation of two-step photolithography combined with electrochemical deposition, the cathode and the electron transport layer formed on the surface of the cathode can be prepared first, or the anode and the hole transport layer formed on the surface of the anode can be prepared first. layer.

Further, in order to simplify the process and reduce the difficulty of the process, in the above formation of the functional layer, the formation of the functional layer on the interdigital electrodes is realized by oxidizing the interdigital electrodes.

In some embodiments, the cathode and the anode included in the interdigitated electrodes can be made of different electrode materials. In this way, the cathode and the anode can be prepared respectively by two-step photolithography. Among them, titanium, zinc, tin, etc. can be selected as the cathode material, and nickel, copper, etc. can be selected as the anode material. In the scheme of oxidizing interdigitated electrodes, further, the cathode (cathode material and pit material are deposited simultaneously) and the anode (anode material and pit material are simultaneously deposited), and the pit is etched with an etching solution. Pit material, after forming the interdigitated electrode with pits, the interdigitated electrode can be heated and oxidized so that the surface of the interdigitated electrode (cathode and anode) is coated with the corresponding metal oxide to form a functional layer (electron transport layer and hole transport layer). For example, TiO ₂ (electron transport layer material) is formed by oxidation of Ti (cathode material), and NiO _x (hole transport layer material) is formed by oxidation of Ni (anode material).

In some embodiments, the thickness of the functional layer may be 9-30 nm. The selection of the thickness of the functional layer and the depth of the pits should always follow the principle that the thickness of the functional layer is smaller than the depth of the pits.

The electrode material can be selected from one or more of conductive metals and conductive metal oxides; wherein, the conductive metal is selected from one or more of zinc, tin, copper, chromium, platinum, nickel, titanium, aluminum, conductive The metal oxide is selected from one or more of ITO and FTO. The pit material can be selected from one or more of gold, aluminum, copper and palladium. The etchant can be selected from the product models of microchemicals company, respectively AU etch 200, CR etch 200/210, CU etch 200 UBM, TechniEtchTMTC, TechniEtch One or more of Al80 etching solutions. AU etch 200 can be used to etch gold-containing materials, CR etch 200/210 can be used to etch chromium-containing materials, CU etch 200 UBM can be used for etching copper-containing materials, TechniEtchTMTC can be used for etching titanium-containing materials, and TechniEtch Al80 can be used for etching aluminum-containing materials.

In the third aspect, please refer to FIG. 2, the present application also provides another method for preparing a light-emitting diode, which includes the following steps:

S401. Forming interdigitated electrodes: depositing electrode materials on the substrate to form a basic electrode with an interdigitated structure; depositing a raised material on the surface of the basic electrode to form a raised interdigitated electrode;

S402, forming a functional layer: forming a functional layer on the interdigitated electrodes, the thickness of the functional layer is smaller than the height of the protrusion; and

S403, forming a light emitting layer: depositing a light emitting layer on the functional layer.

In the above-mentioned another method for preparing light-emitting diodes, the electrode material and the protrusion material are deposited sequentially, so the protrusion material can form protrusions on the surface of the basic electrode formed by the electrode material, thereby increasing the specific surface area of the interdigitated electrode .

In some embodiments, the interdigital electrode includes a plurality of electrode units forming an interdigital structure, and protrusions are formed on each electrode unit. In this way, an increase in the specific surface area can be sufficiently realized.

In some embodiments, the height of each protrusion is smaller than the distance between adjacent electrode units. In this way, it is possible to avoid adverse effects of the protrusion on the electrode unit. In the case of the protrusion structure, the distance between the electrode units may be 12-1000 nm.

In some embodiments, the mass ratio of the electrode material to the protrusion material is 100:0.1˜5.

In some embodiments, the mass ratio of the cathode material to the protrusion material on the cathode is 100:0.1-5, and the mass ratio of the anode material to the protrusion material on the anode is 100:0.1-5.

The protrusion material is the same as the electrode material, and the electrode material is selected from one or more of conductive metals and conductive metal oxides; wherein, the conductive metal is selected from zinc, tin, copper, chromium, platinum, nickel, titanium, aluminum One or more, the conductive metal oxide is selected from one or more of ITO and FTO. Therefore, the protrusion material can be selected with reference to the electrode material. The deposition of the raised material can be achieved by means of electrochemical deposition. Parts such as the substrate, the functional layer, and the light-emitting layer can be selected and prepared with reference to the content mentioned in the first method of manufacturing the light-emitting diode, and will not be repeated here.

The following examples will be used to describe the present application in detail. The following examples are only partial implementations of the present application, and are not intended to limit the present application.

Embodiment one

This embodiment provides a light emitting diode, including:

An interdigital electrode 101, the surface of the interdigital electrode 101 has pits 102;

A functional layer 103, the functional layer 103 is formed on the surface of the interdigital electrode 101; and

The light emitting layer 104 is formed on the surface of the functional layer 103 .

In this embodiment, the depth of the pit 102 is 30 nm, and the thickness of the functional layer 103 is 15 nm. In this embodiment, the pit can also be regarded as a hemispherical structure with a radius of 30 nm.

This embodiment also provides a method for preparing the above-mentioned light-emitting diode, including the following steps:

Step S1: Print AZ1512 photoresist with a thickness of 3um on the glass substrate in a class 100 yellow light clean room, and then heat-treat at 110°C for 2 minutes;

Step S2: using a photolithography mask to expose under a UV lamp, and the exposure time is 5 seconds;

Step S3: Develop the exposed sample in AZ726 developer solution mixed with water (the volume ratio of developer solution to water is 3:1), and the development time is 25 seconds;

Step S4: Using the photoresist as an evaporation mask, under the condition of a vacuum degree of 3×10 ^-4 Pa, the cathode and the anode are formed by evaporating Al by an electron beam, and the evaporation rate of Al is 1 angstroms/second, Simultaneously vapor-deposit gold, the speed is 0.5 angstroms/second, time 533 seconds, vapor-depositing is finished and obtains two doped structure layers respectively corresponding to cathode and anode, the structure schematic diagram of doping structure layer sees Fig. 3, it can be seen that it is by A structure formed jointly by pit material gold and electrode material Al;

Wherein, the thickness of the cathode and the anode are both 80nm;

Step S5: ultrasonically removing the photoresist in acetone;

Step S6: Place the sample in AU etch 200 etching solution, soak it at 20°C for 20 seconds, and then rinse the sample with clean water to obtain the interdigitated electrode 101 with the pit 102 (including the cathode with the pit 102 and anode with dimples 102), see Figure 4;

Step S7: Place the interdigital electrode 101 in a Zn(NO ₃ ) ₂ solution (concentration: 130mM, temperature: 90°C), apply a voltage of -1.3V to the cathode for 120 seconds, stop applying the voltage and use it up Rinse with ionic water to obtain a functional layer 103—the electron transport layer, see FIG. 5;

Step S8: Put the sample washed in the previous step in 0.1M sodium polystyrene sulfonate (PSSNa) and 0.015M 3,4-ethylenedioxythiophene (EDOT) aqueous solution, and apply a voltage of 1.1V on the anode, The duration is 120 seconds, and after the application of the voltage is stopped, it is washed with deionized water to obtain the functional layer 103—the hole transport layer;

Step S9: Print 25nm thick CdZnSe on the electron transport layer and the hole transport layer, the preparation is completed to obtain the light emitting diode, see Figure 6;

Step S10: testing the JVL data of the device to determine the electrical performance of the device.

Embodiment two

This embodiment provides a light emitting diode, including:

An interdigital electrode 101, the interdigital electrode 101 includes a first electrode 201 and a second electrode 202, the surfaces of the first electrode 201 and the second electrode 202 both have pits 102;

A functional layer 103, the functional layer 103 includes a first functional layer 203 and a second functional layer 204, the first functional layer 203 and the second functional layer 204 are respectively formed on the surfaces of the first electrode 201 and the second electrode 202; and

The light emitting layer 104 is formed on the surface of the functional layer 103 .

In this embodiment, the depth of the pit is 30 nm, and the thickness of the functional layer is 15 nm. In this embodiment, the pit can also be regarded as a hemispherical structure with a radius of 30 nm.

This embodiment also provides a method for preparing the above-mentioned light-emitting diode, including the following steps:

Step S1: Print AZ1512 photoresist with a thickness of 3um on the glass substrate in a class 100 yellow light clean room, and then heat-treat at 110°C for 2 minutes;

Step S2: using a photolithography mask to expose under a UV lamp, and the exposure time is 5 seconds;

Step S3: Develop the exposed sample in AZ726 developer solution mixed with water (the volume ratio of developer solution to water is 3:1), and the development time is 25 seconds;

Step S4: Using the photoresist as an evaporation mask, under the condition of a vacuum degree of 3×10 ^-4 Pa, the cathode is formed by evaporating Al by an electron beam. The evaporation rate of Al is 1 angstroms/second, and Gold plating, the speed is 0.5 angstroms/second, the time is 533 seconds, the evaporation is completed to obtain the doped structure layer, see Figure 7, it can be seen from Figure 7 that the first doped structure layer is formed by the pit material gold and the electrode material Al structure; wherein, the thickness of the cathode is 80nm;

Step S5: ultrasonically removing the photoresist in acetone;

Step S6: Put the sample in AU etch 200 etching solution, soak it at 20° C. for 20 seconds, and then rinse the sample with clean water to obtain the first electrode 201 with pits, see FIG. 8 ;

Step S7: Place the first electrode 201 in a Zn(NO ₃ ) ₂ solution (concentration: 130mM, temperature: 90°C), apply a voltage of -1.3V to the first electrode 201 for 120 seconds, and stop applying the voltage Finally, rinse with deionized water to obtain the first functional layer 203—the electron transport layer, see FIG. 9;

Step S8: Repeat steps S1~S3, and again use the photoresist as an evaporation mask to prepare the anode and the corresponding doped structure layer in the same manner and parameters as step S4; without removing the photoresist (Do not repeat step S5), continue to prepare the second electrode 202 with pits according to the method and parameters of step S6;

Step S9: Put the second electrode 202 together with the unremoved photoresist in 0.1M polystyrene sodium sulfonate (PSSNa) and 0.015M 3,4-ethylenedioxythiophene (EDOT) aqueous solution, in the second A voltage of 1.1V was applied to the electrode 202 for 120 seconds. After the application of the voltage was stopped, it was rinsed with deionized water to obtain the second functional layer 204—the hole transport layer, see FIG. 9; in this process, due to the first The electrode 201 is covered under the electron transport layer, unremoved photoresist, thereby being protected from electrochemical deposition;

Step S10: ultrasonically remove the unremoved photoresist mentioned in step 9 in acetone;

Step S11: Spin-coat CdZnSe quantum dot solution (20mg/mL) on the electron transport layer and the hole transport layer to prepare the light-emitting layer 104, the rotation speed is 2000rpm, and the time is 30 seconds, and the preparation is completed to obtain a light-emitting diode, see FIG. 10;

Step S12: testing the JVL data of the device to determine the electrical performance of the device.

Embodiment Three

This embodiment provides a light emitting diode, including:

Interdigitated electrodes, the surface of the interdigitated electrodes has pits;

a functional layer formed on the surface of the interdigitated electrode; and

The light emitting layer is formed on the surface of the functional layer.

In this embodiment, the depth of the pit is 30 nm, and the thickness of the functional layer is 15 nm. In this embodiment, the pit can also be regarded as a hemispherical structure with a radius of 30 nm.

This embodiment also provides a method for preparing the above-mentioned light-emitting diode, including the following steps:

Step S1: Print AZ1512 photoresist with a thickness of 3um on the glass substrate in a class 100 yellow light clean room, and then heat-treat at 110°C for 2 minutes;

Step S2: using a photolithography mask to expose under a UV lamp, and the exposure time is 5 seconds;

Step S3: Develop the exposed sample in AZ726 developer solution mixed with water (the volume ratio of developer solution to water is 3:1), and the development time is 25 seconds;

Step S4: Using the photoresist as an evaporation mask, under the condition of a vacuum degree of 3×10 ^-4 Pa, the cathode is formed by evaporating Ti by an electron beam. The evaporation rate of Ti is 1 angstroms/second, Gold plating, the speed is 0.5 angstroms/second, the time is 533 seconds, and the evaporation is completed to obtain a doped structure layer; wherein, the thickness of the cathode is 80nm;

Step S5: ultrasonically removing the photoresist in acetone;

Step S6: repeating steps S1-S3, and using the photoresist as an evaporation mask again, preparing the anode and the corresponding doped structure layer in the same manner and parameters as step S4; wherein, the material of the anode is Ni;

Step S7: ultrasonically remove the photoresist coated in step 6 in acetone;

Step S8: Place the sample in AU etch 200 etching solution, soak it at 20°C for 20 seconds, and then rinse the sample with clean water to obtain interdigitated electrodes with pits (including cathodes with pits and cathodes with pits the anode);

Step S9: placing the interdigitated electrode in step S8 on a hot stage, heating at 300° C. for 20 minutes, and forming an electron transport layer and a hole transport layer by oxidation of the Ti cathode and the Ni anode, respectively;

Step S10: Spin-coat a CdZnSe quantum dot solution (20 mg/mL) on the electron transport layer and the hole transport layer at a rotation speed of 2000 rpm for 30 seconds to obtain a light-emitting diode;

Step S10: testing the JVL data of the device to determine the electrical performance of the device.

Embodiment Four

This embodiment provides a light emitting diode, including:

Interdigitated electrodes, the surface of the interdigitated electrodes has pits;

a functional layer formed on the surface of the interdigitated electrode; and

The light emitting layer is formed on the surface of the functional layer.

In this embodiment, the depth of the pit is 20nm, and the thickness of the functional layer is 10nm.

This embodiment also provides a method for preparing the above-mentioned light-emitting diode, including the following steps:

Step S1: Spin-coat AZ1512 photoresist on the glass substrate in a class 100 yellow-light clean room at a speed of 3000 for 30 seconds, then heat-treat at 110°C for 2 minutes;

Step S2: using a photolithography mask to expose under a UV lamp, and the exposure time is 6 seconds;

Step S3: Develop the exposed sample in AZ726 developer solution mixed with water (the volume ratio of developer solution to water is 2.5:1), and the development time is 20 seconds;

Step S4: Using the photoresist as an evaporation mask, under the condition of a vacuum degree of 3×10 ^-4 Pa, evaporating Cr by an electron beam to form a cathode and an anode as two basic electrodes, respectively Protruding material is deposited on the surface of the electrode to form a protruding interdigitated electrode; wherein the protruding material is also Cr, the mass ratio of the protruding material on the cathode to the cathode material is 1:100, and the protruding material on the anode and the anode The mass ratio of materials is 1:100;

Step S5: ultrasonically removing the photoresist in acetone;

Step S6: Place the interdigital electrode in Zn(NO ₃ ) ₂ solution (concentration: 120mM, temperature: 85°C), apply a voltage of -1.3V on the cathode for 110 seconds, stop applying the voltage and use deionization Rinse with water to obtain an electron transport layer;

Step S7: Place the sample washed in the previous step in 0.1M sodium polystyrene sulfonate (PSSNa) and 0.015M 3,4-ethylenedioxythiophene (EDOT) aqueous solution, and apply a voltage of 1.1V on the anode, The duration is 110 seconds, after the application of the voltage is stopped, it is washed with deionized water to obtain a hole transport layer;

Step S8: Spin-coat a CdTe/ZnS quantum dot solution (20 mg/mL) on the electron transport layer and the hole transport layer at a rotation speed of 2200 rpm for 25 seconds to obtain a light emitting diode.

comparative example

This comparative example provides a conventional back-contact device, the interdigitated electrodes in its structure are conventional electrodes with finger-like or comb-like periodic patterns, without pits or protrusions, and the electrodes, functional layers, light-emitting layers The thickness is the same as that of the functional layer and the light-emitting layer in the first embodiment, and the material used for each structural layer is also the same as that used for each structural layer in the first embodiment. The preparation method of the conventional back contact type device that this comparative example provides is as follows:

Step S1: Print AZ1512 photoresist with a thickness of 3um on the glass substrate in a class 100 yellow light clean room, and then heat-treat at 110°C for 2 minutes;

Step S2: using a photolithography mask to expose under a UV lamp, and the exposure time is 5 seconds;

Step S3: Develop the exposed sample in AZ726 developer solution mixed with water (the volume ratio of developer solution to water is 3:1), and the development time is 25 seconds;

Step S4: Using the photoresist as an evaporation mask, under the condition of a vacuum degree of 3×10 ^-4 Pa, the cathode and the anode are formed by evaporating Al by an electron beam, and the evaporation rate of Al is 1 angstroms/second, The time is 800 seconds, and the thickness of both the cathode and the anode is 80nm;

Step S5: ultrasonically removing the photoresist in acetone;

Step S6: Place the sample in a Zn(NO ₃ ) ₂ solution (130mM concentration, 90°C), apply a voltage of -1.3V on the cathode for 120 seconds, and rinse with deionized water after the application of the voltage is stopped Clean, get the electron transport layer;

Step S7: Place the sample washed in the previous step in 0.1M sodium polystyrene sulfonate (PSSNa) and 0.015M 3,4-ethylenedioxythiophene (EDOT) aqueous solution, and apply a voltage of 1.1V on the anode, The duration is 120 seconds, and after the application of the voltage is stopped, it is washed with deionized water to obtain a hole transport layer;

Step S8: Spin-coat a CdZnSe quantum dot solution (20 mg/mL) on the electron transport layer and the hole transport layer at a rotation speed of 2000 rpm for 30 seconds to obtain a back contact device;

Step S9: testing the JVL data of the device to determine the electrical performance of the device.

In order to verify the device performance of the light-emitting diodes provided in the embodiments of the present invention, the devices provided in Examples 1 to 3 and Comparative Examples were respectively subjected to a voltage-brightness performance test and a brightness-external quantum efficiency performance test. The test results are shown in Figure 11 and Figure 11 respectively. Fig. 12, wherein a~d respectively represent the test result curves of the devices provided in the first embodiment, the second embodiment, the third embodiment and the comparative example. It can be seen from Figure 11 that under the same voltage, the brightness of the device provided by the embodiment of the present invention is higher; it can be seen from Figure 12 that under the same brightness, the brightness of the device provided by the embodiment of the present invention is higher. The external quantum efficiency is higher, so it can be known that the photoelectric performance of the device provided by the embodiment of the present invention is better. A light-emitting diode provided by the embodiment of the present application and its preparation method have been introduced in detail above. In this paper, the principle and implementation of the present application have been explained by using specific examples. The description of the above embodiment is only used to help understand the present application. The method of application and its core idea; at the same time, for those skilled in the art, according to the idea of this application, there will be changes in the specific implementation and scope of application. In summary, the content of this specification should not be understood as Limitations on this Application.

Claims (20)

1. A light emitting diode, comprising:

   Interdigital electrodes, the surface of the interdigital electrodes is formed with pits or protrusions;

   a functional layer, the functional layer is formed on the surface of the interdigital electrode, and the thickness of the functional layer is smaller than the depth of the pit or the height of the protrusion; and

   A light emitting layer, the light emitting layer is formed on the surface of the functional layer.
2. The light emitting diode according to claim 1, wherein the depth of the pit or the height of the protrusion is 11-70 nm.
3. The light emitting diode according to claim 1 or 2, wherein the depth of the pit or the height of the protrusion is 15-50 nm.
4. The light emitting diode according to claim 1, wherein the functional layer is selected from one or more of a charge injection layer, a charge transport layer, and a charge blocking layer.
5. The light emitting diode according to claim 1, wherein the interdigitated electrode comprises a first electrode and a second electrode forming an interdigitated structure, the surfaces of the first electrode and the second electrode are both formed with pits or raised;

   The functional layer includes a first functional layer and a second functional layer, the first functional layer is formed on the surface of the first electrode, the second functional layer is formed on the surface of the second electrode, and the first functional layer is formed on the surface of the second electrode. Both the thicknesses of the first functional layer and the second functional layer are smaller than the depth of the pit or the height of the protrusion;

   The luminescent layer is formed on the surfaces of the first functional layer and the second functional layer, and covers a space area between the first functional layer and the second functional layer.
6. The light emitting diode according to claim 1, wherein the interdigitated electrode comprises a first electrode and a second electrode forming an interdigitated structure, the first electrode is a cathode, and the material of the cathode is selected from zinc, tin, One or more of titanium, aluminum, ITO, FTO.
7. The light emitting diode according to claim 1, wherein the interdigitated electrode comprises a first electrode and a second electrode forming an interdigitated structure, the second electrode is an anode, and the material of the anode is selected from copper, nickel, One or more of aluminum, chromium, platinum, ITO, FTO.
8. The light emitting diode according to claim 1, wherein the light emitting layer is a quantum dot light emitting layer, and the material of the quantum dot light emitting layer is selected from CdSe, CdS, ZnSe, ZnS, CdTe, ZnTe, CdZnS, CdZnSe, CdZnTe, ZnSeS, ZnSeTe, ZnTeS, CdSeS, CdSeTe, CdTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdSeSTe, ZnSeSTe, InP, GaP, GaAs, InAs, InAsP, GaAsP, InGaP, InGaAs, PbS, PbSe, PbTe, PbSeS, PbSeTe, CdZnSe/ ZnS, CdZnSeS/ZnS, CdTe/ZnS, CdZnSe/ZnS, CdZnSeS/ZnS, CdTe/ZnS, CdTe/CdSe, CdTe/ZnTe, CdSe/CdS, CdSe/ZnS, InP/ZnS, inorganic perovskite semiconductors, organic - one or more of inorganic hybrid perovskite semiconductors; wherein, the general formula of the inorganic perovskite semiconductors is AMX ₃ , wherein A is Cs ⁺ , and M is selected from Pb ²⁺ , Sn ^{2 +} , Cu ²⁺ , Ni ²⁺ , Cd ²⁺ , Cr ²⁺ , Mn ²⁺ , Co ²⁺ , Fe ²⁺ , Ge ²⁺ , Yb ²⁺ , Eu ²⁺ , X is selected from One of Cl ^- , Br ^- , I ^- ; the general formula of the organic-inorganic hybrid perovskite semiconductor is BMX ₃ , wherein B is an organic amine cation, and M is selected from Pb ²⁺ , Sn ²⁺ , Cu ²⁺ , Ni ²⁺ , Cd ²⁺ , Cr ²⁺ , Mn ²⁺ , Co ²⁺ , Fe ²⁺ , Ge ²⁺ , Yb ²⁺ , Eu ²⁺ , X is selected from Cl One of ^- , Br ^- , I ^- .
9. The light emitting diode according to claim 1, wherein the material of the protrusion is the same as that of the interdigital electrode.
10. A method for preparing a light emitting diode, comprising the following steps:

    providing a substrate, an electrode material, a pit material for forming pits, and an etching solution for etching the pit material;

    Formation of interdigitated electrodes: depositing the electrode material and the pit material on the substrate at the same time to form a doped structure layer with an interdigitated structure; using the etching solution to etch the doped structure layer The pit material forms an interdigitated electrode having pits;

    Forming a functional layer: forming a functional layer on the interdigital electrodes, the thickness of the functional layer being smaller than the depth of the pit; and

    Light-emitting layer formation: a light-emitting layer is deposited on the functional layer.
11. The method for manufacturing a light emitting diode according to claim 10, wherein the mass ratio of the electrode material to the pit material is 0.1-10:1.
12. The method for manufacturing a light emitting diode according to claim 10, wherein the interdigitated electrodes include a first electrode and a second electrode, and the functional layer includes a first functional layer and a second functional layer;

    The formation of the interdigitated electrodes and the formation of the functional layer include the formation of the first electrode, the formation of the first functional layer, the formation of the second electrode and the formation of the second functional layer, and the steps include:

    Depositing the material of the first electrode and the material of the pit simultaneously on the substrate to form a first doped structure layer corresponding to the first electrode in the interdigitated structure; using the etching solution to etch etching the pit material in the first doped structure layer to form a first electrode with pits;

    forming a first functional layer on the first electrode, the thickness of the first functional layer is smaller than the depth of the pit;

    shielding the first functional layer, depositing the material of the second electrode and the material of the pit on the substrate at the same time, forming a second doped structure layer corresponding to the second electrode in the interdigitated structure ; using the etchant to etch the pit material in the second doped structure layer to form a second electrode with pits;

    A second functional layer is formed on the second electrode, and the thickness of the second functional layer is smaller than the depth of the pit.
13. The method for manufacturing a light emitting diode according to claim 10, wherein in the formation of the functional layer, the formation of the functional layer on the interdigital electrode is realized by oxidizing the interdigital electrode.
14. The method for preparing a light emitting diode according to claim 10, wherein the thickness of the functional layer is 9-30 nm.
15. The method for preparing a light-emitting diode according to claim 10, wherein the electrode material is selected from one or more of conductive metals and conductive metal oxides; wherein the conductive metal is selected from zinc, tin, copper, One or more of chromium, platinum, nickel, titanium, aluminum, the conductive metal oxide is selected from one or more of ITO, FTO; the pit material is selected from gold, aluminum, copper, palladium One or more of them; the etching solution is selected from one or more of AU etch 200, CR etch 200/210, CU etch 200 UBM, TechniEtchTMTC, and TechniEtch Al80 in product models.
16. A method for preparing a light emitting diode, comprising the following steps:

    providing substrate, electrode material and bump material for bump formation;

    Forming interdigitated electrodes: depositing the electrode material on the substrate to form a basic electrode with an interdigitated structure; depositing the raised material on the surface of the basic electrode to form a raised interdigitated electrode;

    Forming a functional layer: forming a functional layer on the interdigital electrodes, the thickness of the functional layer being smaller than the height of the protrusion; and

    Light-emitting layer formation: a light-emitting layer is deposited on the functional layer.
17. The method for manufacturing a light emitting diode according to claim 16, wherein the interdigitated electrode comprises a plurality of electrode units forming an interdigitated structure, and the protrusion is formed on each of the electrode units.
18. The method for manufacturing a light emitting diode according to claim 16, wherein the interdigitated electrode comprises a plurality of electrode units forming an interdigitated structure, each of the electrode units is formed with the protrusion, each of the electrode units The heights of the protrusions are all smaller than the distance between the adjacent electrode units.
19. The method for manufacturing a light emitting diode according to claim 16, wherein the mass ratio of the electrode material to the protrusion material is 100:0.1-5.
20. The method for preparing a light-emitting diode according to claim 16, wherein the protrusion material is the same as the electrode material, and the electrode material is selected from one or more of conductive metals and conductive metal oxides; wherein, The conductive metal is selected from one or more of zinc, tin, copper, chromium, platinum, nickel, titanium, and aluminum, and the conductive metal oxide is selected from one or more of ITO and FTO.