Light-emitting diode chip, display screen, and electronic device

Abstract

A light-emitting diode (LED) chip, a display screen, and an electronic device, relating to the technical field of display, for use in mitigating the problem of influence on the quality of the entire micro display screen caused by a red micro-LED chip. A covering layer in the LED chip covers a light-emitting layer of a light-emitting device. The covering layer comprises a substrate layer and a nano / micro column array. The nano / micro column array structure comprises multiple nano / micro columns, the ends of the nano / micro columns away from the light-emitting layer pass through the substrate layer, and the extension direction of the nano / micro columns is perpendicular to the light-emitting layer. The material used in the nano / micro columns comprises a color conversion material, and the refractive index of the color conversion material is greater than that of the material used in the substrate layer. Alternatively, the material used in the substrate layer comprises a color conversion material, and the refractive index of the color conversion material is greater than that of the material used in the nano / micro columns. Total reflection occurs at an interface between an optically denser medium having a larger refractive index and an optically thinner medium having a smaller refractive index, so that an optical path length, in the color conversion material, of initial light emitted by the light-emitting device is increased.

Description

Light-emitting diode chip, display screen, and electronic equipment

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on June 30, 2023, with application number 202310804134.8 and application name “A light-emitting diode chip, display screen and electronic device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of display technology, and in particular to a light emitting diode chip, a display screen, and an electronic device. Background Art

[0003] With the development of display technology, the production process of micro-components has become a development trend in display panels, such as micro (mirco or mini) light emitting diode (LED) technology. Micro LED displays are equipped with an array of micro LEDs, each of which can be driven and illuminated individually as a subpixel, enabling the display to present a more detailed and contrasty image. The above-mentioned micro LED displays can be equipped with blue micro LEDs, green micro LEDs, and red micro LEDs.

[0004] Currently, red micro-LEDs can be fabricated using aluminum indium gallium phosphide (AlInGaP) or indium gallium nitride (InGaN). However, the high non-radiative recombination rate on the surface of AlInGaP limits luminous efficiency. Furthermore, InGaN can cause color shift in red micro-LEDs at varying current densities, compromising the quality of the entire micro-LED display.

[0005] Summary of the Invention

[0006] The present application provides a light-emitting diode chip, a display screen, and an electronic device for alleviating the problem that the red light micro-LED chip affects the quality of the entire micro-LED display screen.

[0007] To achieve the above objectives, this application adopts the following technical solutions:

[0008] In one aspect of the present application, a light-emitting diode chip is provided. The light-emitting diode chip may include a light-emitting device and a covering layer. The light-emitting device includes a light-emitting layer, and the covering layer covers the light-emitting layer. The covering layer may include a substrate layer and a nano-pillar array. The vertical projection of the light-emitting layer on the substrate layer is located within the range of the substrate layer. The nano-pillar array structure may be provided in the substrate layer, and the nano-pillar array structure includes a plurality of nano-pillars, wherein one end of the nano-pillars facing away from the light-emitting layer penetrates the substrate layer, and the extension direction of the nano-pillars is perpendicular to the light-emitting layer. In addition, the material used for the nano-pillars includes a color conversion material, and the refractive index of the color conversion material is greater than the refractive index of the material used for the substrate layer. Alternatively, the material used for the substrate layer includes a color conversion material, and the refractive index of the color conversion material is greater than the refractive index of the material used for the nano-pillars.

[0009] In summary, the LED chip provided in the embodiments of the present application includes a light-emitting device and a covering layer covering the light-emitting layer of the light-emitting device. The covering layer includes a substrate layer and a plurality of nano-pillars disposed in the substrate layer. The material used for the nano-pillars may include a color-conversion material, and the refractive index of the color-conversion material may be greater than the refractive index of the material used for the substrate layer. Alternatively, the material used for the substrate layer may include a color-conversion material, and the refractive index of the color-conversion material may be greater than the refractive index of the material used for the nano-pillars. Thus, on the one hand, the nano-pillars or substrate layer containing the color-conversion material in the LED chip can convert the initial light from the light-emitting device, such as blue light, into desired light, such as red light. This avoids the limited luminous efficiency or color shift issues that occur in red LED chips made of AlInGaP or InGaN, thereby alleviating the problem of red micro-LED chips affecting the quality of the entire micro-LED display. On the other hand, the structure primarily composed of the color-conversion material, such as the nano-pillars, is an optically dense medium relative to surrounding components, such as the substrate layer. Alternatively, a structure primarily composed of color-conversion material, such as a substrate layer, can be an optically denser medium relative to surrounding components, such as nanopillars. This allows at least a portion of light incident on the interface between the optically denser and optically less dense media to undergo total internal reflection. This reflected light can then continue to propagate within the structure composed of the color-conversion material (nanopillars or substrate layer). This increases the optical path length of the initial light emitted by the light-emitting device within the color-conversion material and the duration of its interaction with the color-conversion material, thereby improving color conversion efficiency, such as red light, while reducing the likelihood of blue light leakage from the light-emitting diode chip's light-emitting side.

[0010] In an optional embodiment, the nano-micro-pillar array structure has at least two periodic patterns, and the vertical projection of the line connecting the geometric centers of at least two nano-micro-pillars on the light-emitting layer constitutes a periodic pattern. In this way, since the multiple nano-micro-pillars in the nano-micro-pillar array structure of the light-emitting diode chip can be arranged in a periodic and orderly manner, when the nano-micro-pillars use color conversion materials, the light emission directions of the converted light (red light or green light) emitted by each nano-micro-pillar can be consistent or approximately consistent, achieving the effect of collimating the emitted light, thereby reducing the light emission angle of the light-emitting diode chip. Alternatively, when the substrate layer uses a color conversion material, the light emission directions of the converted light (red light or green light) emitted by the substrate layer located between the multiple periodically and orderly arranged nano-micro-pillars are consistent or approximately consistent, achieving the effect of collimating the emitted light, thereby reducing the light emission angle of the light-emitting diode chip.

[0011] In an optional embodiment, at least two periodic patterns have the same shape, so as to achieve a periodic and orderly arrangement of the plurality of nano-micro-pillars in the nano-micro-pillar array structure.

[0012] In an optional embodiment, the spacing between two adjacent nano-micro-pillars forming the same periodic pattern is the same, so as to achieve a periodic and orderly arrangement of multiple nano-micro-pillars in the nano-micro-pillar array structure.

[0013] In an optional embodiment, at least two periodic patterns are nested in sequence to achieve a periodic and orderly arrangement of multiple nano-micro-pillars in the nano-micro-pillar array structure.

[0014] In an optional embodiment, the geometric centers of at least two periodic patterns of the nano-micro-pillar array structure overlap, so as to achieve a periodic and orderly arrangement of multiple nano-micro-pillars in the nano-micro-pillar array structure.

[0015] In an optional embodiment, at least two periodic pattern arrays are arranged to achieve a periodic and orderly arrangement of multiple nano-micro-pillars in the nano-micro-pillar array structure.

[0016] In an optional embodiment, the vertical projection areas of at least two nano-micro-pillars constituting the same periodic pattern on the light-emitting layer are different. This application does not limit the vertical projection areas of at least two nano-micro-pillars constituting the same periodic pattern on the light-emitting layer.

[0017] In an optional embodiment, the periodic pattern is a circle, a triangle, a rectangle or a regular polygon, so that the periodic and orderly arrangement of the plurality of nano-micropillars can be similar to the periodic arrangement of a photonic crystal microstructure.

[0018] In an optional embodiment, the vertical projection of the nano-microcolumn on the light-emitting layer is at least one of a circle or a polygon. The present application does not limit the shape of the vertical projection of the nano-microcolumn on the light-emitting layer.

[0019] In one optional embodiment, the color-conversion material is an optically anisotropic material and is oriented along a first direction perpendicular to the light-emitting layer. This allows the dominant light emission direction of the color-conversion material to align with the first direction, collimating the light emitted from the LED chip and thereby reducing the light emission angle of the LED chip. For example, the light emission angle of an LED chip with the color-conversion material in this oriented arrangement can be tested using an optical instrument. The light emission angle can be less than 65°, for example, approximately 45°.

[0020] In one optional embodiment, the color conversion material includes a quantum dot material, and the quantum dot material is shaped as at least one of nanorods, nanosheets, or nanospheres. The quantum dot material is optically anisotropic, thereby facilitating the alignment of the color conversion material along the first direction.

[0021] In an optional embodiment, the light-emitting device further includes a first semiconductor layer and a second semiconductor layer. The first semiconductor layer is stacked with the light-emitting layer, and the first semiconductor layer includes a first semiconductor material. The second semiconductor layer is stacked on a side of the light-emitting layer facing away from the first semiconductor layer, and the second semiconductor layer includes a second semiconductor material. The first semiconductor material and the second semiconductor material have different doping types. A covering layer is disposed on a side of the second semiconductor layer facing away from the light-emitting layer. In this case, the light-emitting diode chip can be a micro (or mini) light-emitting diode chip, and the light-emitting device of the light-emitting diode chip can be a micro (or mini) light-emitting diode light-emitting device.

[0022] In an optional embodiment, the light-emitting device further includes a driving backplane, a first electrode, and a second electrode. The driving backplane is disposed on the side of the first semiconductor layer facing away from the light-emitting layer. The first electrode is disposed between the first semiconductor layer and the driving backplane, and the first electrode is electrically connected to the driving backplane. The second electrode is disposed on the side of the second semiconductor layer facing away from the light-emitting layer, and the second electrode is electrically connected to the driving backplane. In this case, the driving backplane of the light-emitting device can be electrically connected to the first electrode and the second electrode, so that the pixel driving circuit in the driving backplane can provide voltages to the first electrode and the second electrode of the light-emitting device, respectively, to form an external electric field. The external electric field can control the current flowing through the light-emitting layer of the light-emitting device, thereby controlling the number of photons excited in the light-emitting layer, thereby achieving the purpose of controlling the brightness of the light-emitting device.

[0023] In one optional embodiment, the light-emitting device further comprises a first semiconductor layer, laminated on a side of the light-emitting layer facing away from the cover layer, and comprising a first semiconductor material. If the material used for the nanopillars comprises a color-conversion material, the material used for the substrate layer comprises a second semiconductor material. Alternatively, if the material used for the substrate layer comprises a color-conversion material, the material used for the nanopillars comprises a second semiconductor material. The first and second semiconductor materials have different doping types. Therefore, if the material used for the nanopillars comprises a color-conversion material, the nanopillars can be disposed within a substrate layer primarily composed of the second semiconductor material. Since the substrate layer composed of the second semiconductor material can be disposed on the light-emitting side of the light-emitting layer (facing away from the driver backplane), the distance between the nanopillars and the light-emitting layer can be reduced. This reduces the distance between the initial light emitted by the light-emitting layer, such as blue light, and the color-conversion material (e.g., nanopillars), thereby reducing the probability of light loss during the initial light's entry into the color-conversion material and thereby improving the color conversion efficiency. Alternatively, for example, if the substrate layer includes a color-converting material, the nanopillars may include a second semiconductor material. Similarly, the nanopillars and substrate layer may be positioned on the light-emitting side of the light-emitting layer (facing away from the driver backplane), minimizing the distance between the initial light emitted by the light-emitting layer and the color-converting material (e.g., nanopillars).

[0024] In an optional embodiment, the light-emitting device further includes a driving backplane, a first electrode, and a second electrode. The driving backplane is disposed on a side of the first semiconductor layer facing away from the light-emitting layer. The first electrode is disposed between the first semiconductor layer and the driving backplane, and the first electrode is electrically connected to the driving backplane. A portion of the second electrode is located between the substrate layer and the nano-pillars. The second electrode is electrically connected to the driving backplane, and the second electrode includes a transparent conductive material, thereby allowing light emitted by the light-emitting device to pass through, allowing the light to enter the nano-pillars or substrate layer having the color conversion material. The technical effects of the above-mentioned driving backplane, first electrode, and second electrode are the same as described above and will not be repeated here.

[0025] In one optional embodiment, the LED chip includes at least two light-emitting devices, wherein the first electrodes of adjacent light-emitting devices are connected to form an integral structure, and the second electrodes of adjacent light-emitting devices are insulated. In this way, by applying different voltages to the second electrodes of different light-emitting devices, the brightness of different light-emitting devices can be individually controlled.

[0026] In one optional embodiment, the light-emitting layer is a semiconductor active layer. The first semiconductor material is an N-type doped semiconductor material, and the second semiconductor material is a P-type doped semiconductor material. Alternatively, the first semiconductor material is a P-type doped semiconductor material, and the second semiconductor material is an N-type doped semiconductor material. In this way, a PN junction can be formed between the first semiconductor layer and the second semiconductor layer. The light-emitting layer is located in the active region of this PN junction.

[0027] In one optional embodiment, the light-emitting layer is an organic light-emitting layer. Based on this, the pixel driver circuit in the driver backplane of the light-emitting device can apply voltages to the first and second electrodes of the light-emitting device to form an external electric field. This external electric field can cause holes to be generated at the first electrode and electrons to be generated at the second electrode. Furthermore, these holes and electrons migrate to the light-emitting layer. The electrons and holes encounter each other in the organic light-emitting layer, generating energy excitons in the light-emitting layer, thereby stimulating the light-emitting molecules in the organic light-emitting layer to emit light.

[0028] In an optional embodiment, when the material used for the nano-microcolumns includes a color conversion material, the material used for the substrate layer includes at least one of silicon monoxide, silicon dioxide, and aluminum oxide. The material used for the substrate layer can be a low-refractive-index material with a refractive index of less than 2, for example, a refractive index of 1.4 to 1.6. Alternatively, when the material used for the substrate layer includes a color conversion material, the material used for the nano-microcolumns includes at least one of silicon monoxide, silicon dioxide, and aluminum oxide. The material used for the nano-microcolumns can be a low-refractive-index material with a refractive index of less than 2, for example, a refractive index of 1.4 to 1.6.

[0029] In an optional embodiment, when the material used for the nano-micro-pillars includes a color conversion material, at least the portion of the nano-micro-pillars in contact with the substrate layer may be made of the color conversion material. Accordingly, the material used for the substrate layer may include at least one of silicon monoxide, silicon dioxide, and aluminum oxide. Alternatively, when the material used for the substrate layer includes a color conversion material, at least the portion of the substrate layer that encapsulates the nano-micro-pillars may be made of the color conversion material. Accordingly, the material used for the nano-micro-pillars may include at least one of silicon monoxide, silicon dioxide, and aluminum oxide. This allows light incident on the interface between the substrate layer and the nano-micro-pillars to undergo total internal reflection.

[0030] In an optional embodiment, when the material used for the nano-microcolumns includes a color conversion material, the height of the nano-microcolumns is 0.1 μm to 10 μm. When the height H1 of the nano-microcolumns is 0.1 μm to 10 μm, the conversion efficiency of the initial light (for example, blue light) incident on the light-emitting device in the nano-microcolumns can be improved, and the probability of light loss of the preset light (for example, red light and green light) that has been converted by the color conversion material can be reduced, thereby improving the luminous efficiency of the LED light-emitting chip 20. Alternatively, when the material used for the substrate layer includes a color conversion material, the thickness of the substrate layer is 0.1 μm to 10 μm. The technical effects of the thickness range of the substrate layer are the same as described above and will not be repeated here.

[0031] In an optional embodiment, a light-emitting diode chip includes a first light-emitting device, a second light-emitting device, a first cover layer, and a second cover layer, wherein the first cover layer covers the light-emitting layer of the first light-emitting device, and the second cover layer covers the light-emitting layer of the second light-emitting device. The light-emitting diode chip further includes a planar layer and a retaining wall. The planar layer is disposed between the first light-emitting device and the second light-emitting device, and is connected to the first light-emitting device and the second light-emitting device. The surface of the planar layer facing away from the driver backplate can be flush with the surface of the light-emitting device (e.g., the first light-emitting device and the second light-emitting device) facing away from the driver backplate. The retaining wall is disposed within the planar layer and is located between the first light-emitting device and the second light-emitting device. A portion of the planar layer is separated between the retaining wall and the first light-emitting device, and between the retaining wall and the second light-emitting device. The base material layer of the first cover layer and the base material layer of the second cover layer are connected to form an integral structure and cover the retaining wall. The initial light emitted by the first light-emitting device and the second light-emitting device can be blue light, and the first cover layer and the second cover layer respectively perform color conversion on the initial light emitted by the first light-emitting device and the second light-emitting device, with the converted light being red and green light, respectively.

[0032] In an optional embodiment, the light-emitting diode chip includes a first light-emitting device, a second light-emitting device, a first covering layer, and a second covering layer, wherein the first covering layer covers the light-emitting layer of the first light-emitting device, and the second covering layer covers the light-emitting layer of the second light-emitting device. The light-emitting diode chip also includes a retaining wall. The retaining wall is disposed between the first light-emitting device and the second light-emitting device and between the first covering layer and the second covering layer. The retaining wall is connected to the first light-emitting device, the second light-emitting device, the substrate layer of the first covering layer, and the substrate layer of the second covering layer. A flat layer is not required in the above-mentioned light-emitting diode chip. The technical effects of the first light-emitting device, the second light-emitting device, the first covering layer, and the second covering layer are the same as those described above and will not be repeated here.

[0033] In an optional embodiment, the light-emitting diode chip includes a first light-emitting device, a second light-emitting device, and a third light-emitting device, and the initial light emitted by the first light-emitting device, the second light-emitting device, and the third light-emitting device is the same. The light-emitting diode chip includes a first covering layer and a second covering layer; the light-emitting diode chip also includes a transparent structure; the first covering layer covers the light-emitting layer of the first light-emitting device, the second covering layer covers the light-emitting layer of the second light-emitting device, and the transparent structure covers the light-emitting layer of the third light-emitting device. The light from the first covering layer, the light from the second covering layer, and the initial light are respectively three primary colors. In this way, the initial light emitted by the first light-emitting device, the second light-emitting device, and the third light-emitting device can be blue light. The first covering layer and the second covering layer can respectively perform color conversion on the initial light emitted by the first light-emitting device and the second light-emitting device, and the converted light is red light and green light, respectively. In addition, the transparent structure can directly transmit the initial light emitted by the third light-emitting device, i.e., blue light. Therefore, the light from the first covering layer, the second covering layer and the transparent structure are the three primary colors respectively, and the areas where the first light-emitting device, the second light-emitting device and the third light-emitting device are located can be used as red sub-pixels, green sub-pixels and blue sub-pixels respectively, thereby enabling the light-emitting diode chip to achieve full-color display.

[0034] In an optional embodiment, the light emitting diode chip may further include an encapsulation layer, which is located on the surface of the cover layer facing away from the light emitting device. The encapsulation layer may include at least one of an organic encapsulation film layer and an inorganic encapsulation film layer.

[0035] Another aspect of the present application provides a display screen having multiple pixel regions. The display screen includes any of the aforementioned multiple LED chips, each including a light-emitting device. The multiple LED chips are arranged in an array, with at least three adjacent LED chips emitting light of the three primary colors located within the same pixel region. Alternatively, the display screen includes any of the aforementioned LED chips, the LED chip including multiple light-emitting devices arranged in an array, with at least three adjacent light-emitting devices emitting light of the three primary colors located within the same pixel region. This display screen has the same technical effects as the LED chips provided in the aforementioned embodiments and will not be further described here.

[0036] Another aspect of the present application provides an electronic device comprising a processor and the display screen described above. The display screen is electrically connected to the processor, and the processor is configured to control the display screen to display an image. This electronic device has the same technical effects as the light-emitting diode chip provided in the aforementioned embodiment, and will not be further described here. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] FIG1 is a schematic structural diagram of an electronic device provided in an embodiment of the present application;

[0038] FIG2A is a schematic structural diagram of the display screen in FIG1 ;

[0039] FIG2B is a top view taken along the direction A in FIG2A ;

[0040] FIG3A is a schematic diagram of another structure of the display screen in FIG1 ;

[0041] FIG3B is a top view taken along the direction B in FIG3A ;

[0042] FIG4 is a cross-sectional view taken along the dotted line O1-O2 in FIG3B;

[0043] FIG5A is a schematic structural diagram of the light emitting device in FIG4 ;

[0044] FIG5B is another schematic structural diagram of the light emitting device in FIG4 ;

[0045] FIG6 is another cross-sectional view taken along the dotted line O1-O2 in FIG3B;

[0046] FIG7A is a top view taken along the direction C in FIG6 ;

[0047] FIG7B is a cross-sectional view taken along the dotted line Q1-Q2 in FIG7A;

[0048] FIG8A is another top view taken along the direction C in FIG6 ;

[0049] FIG8B is a cross-sectional view taken along the dotted line Q3-Q4 in FIG8A;

[0050] FIG9 is a schematic structural diagram of a light-emitting diode chip provided by a related technical solution;

[0051] FIG10A is a diagram illustrating a periodic and orderly arrangement of multiple nano-micro-pillars in the nano-micro-pillar array structure in FIG6 ;

[0052] FIG10B is a diagram illustrating another periodic and orderly arrangement of multiple nano-micro-pillars in the nano-micro-pillar array structure in FIG6 ;

[0053] FIG10C is a diagram illustrating another periodic and orderly arrangement of multiple nano-micro-pillars in the nano-micro-pillar array structure in FIG6 ;

[0054] FIG11A is a diagram illustrating a configuration of the orientation distribution of the color conversion material of the nano-columns in FIG6;

[0055] FIG11B is a diagram illustrating a configuration of the orientation distribution of the color conversion material of the nano-columns in FIG6;

[0056] FIG11C is a diagram illustrating a configuration of the orientation distribution of the color conversion material of the nano-columns in FIG6;

[0057] FIG12A is a schematic diagram of the light emission pattern of the nanosheet in FIG11B ;

[0058] FIG12B is a schematic diagram of the structure of the nanosheet in FIG11B ;

[0059] FIG13 is a cross-sectional view taken along the dotted line O3-O4 in FIG3B;

[0060] FIG14A is a schematic diagram of a partial structure of a light-emitting diode chip provided in an embodiment of the present application;

[0061] FIG14B is a schematic diagram of another partial structure of a light-emitting diode chip provided in an embodiment of the present application;

[0062] FIG15 is a flow chart of a method for manufacturing a light-emitting diode chip according to an embodiment of the present application;

[0063] Figure 16 (a), (b), (c) and (d) are schematic diagrams of a manufacturing process of a light emitting diode chip;

[0064] Figure 17 (a) and (b) are schematic diagrams of another manufacturing process of a light-emitting diode chip;

[0065] FIG18 is another cross-sectional view taken along the dotted line O3-O4 in FIG3B;

[0066] FIG19 is another cross-sectional view taken along the dotted line O3-O4 in FIG3B;

[0067] FIG20 is a cross-sectional view taken along the dotted line O5-O6 in FIG3B;

[0068] FIG21 is another cross-sectional view taken along the dotted line O1-O2 in FIG3B;

[0069] Figures (a), (b) and (c) in Figure 22 are schematic diagrams of another manufacturing process of a light-emitting diode chip;

[0070] (a) and (b) in FIG. 23 are schematic diagrams of another manufacturing process of a light emitting diode chip.

[0071] Figure 1: 01-electronic device; 10-display screen; 11-processor; 100-pixel; 20-LED chip; 201-light-emitting device; 2011-light-emitting layer; 200-driving backplane; 211-first electrode; 212-second electrode; 2012-first semiconductor layer; 2013-second semiconductor layer; 2014-hole injection layer; 2015-hole transport layer; 2016-electron transport layer; 2017-electron injection layer; 202-covering layer; 2021-substrate layer; 2022-nano-micro-pillar array structure; 2023-nano-micro-pillar; 30-periodic pattern; 20231-nano Meter column; 20232-nanosheet; 20233-nanosphere; 202a-first covering layer; 202b-second covering layer; 201a-first light-emitting device; 201b-second light-emitting device; 40-flat layer; 41-blocking wall; 50-dielectric layer; 51-mask; 501-nanohole; 60-encapsulation layer; 400-transparent structure; 201c-third light-emitting device; 202c-third covering layer; 61-photoresist. DETAILED DESCRIPTION

[0072] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0073] In the following, the terms "first," "second," etc., are used for descriptive convenience only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Thus, a feature specified as "first," "second," etc. may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0074] In this application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed mechanical connection, a detachable mechanical connection, or an integrated connection; or, "connection" can be a direct connection or an indirect connection through an intermediate medium.

[0075] In addition, unless otherwise clearly specified and limited, the term "electrical connection" should be understood in a broad sense. For example, "electrical connection" can be a direct electrical connection, for example, physical contact and electrical conduction between two components. It can also be understood as the electrical connection between different components in the circuit structure through physical lines such as printed circuit board (PCB) copper foil or wires that can transmit electrical signals to transmit electrical signals; or, "electrical connection" can be an indirect electrical connection between two components through an intermediate medium; or, "electrical connection" can be an electrical connection between two components in an air / non-contact manner, for example, two components are electrically connected by capacitive coupling to transmit electrical signals.

[0076] In the embodiments of the present application, the descriptions "vertical" and "parallel" respectively indicate approximately vertical and approximately parallel within a certain error range, and the error range may be a range in which the deviation angle relative to absolute vertical and absolute parallel is less than or equal to 5°, 8° or 10°, respectively, and no specific limitation is made here.

[0077] In the embodiments of the present application, directional terms such as "up", "down", "left" and "right" may be defined including but not limited to the orientation relative to the components schematically placed in the drawings. It should be understood that these directional terms may be relative concepts, which are used for relative description and clarification, and may change accordingly according to changes in the orientation of the components in the drawings.

[0078] In the drawings of the embodiments of the present application, components are represented by guide lines with arrows; parts are represented by guide lines only; and hollow structures such as openings and holes are represented by guide lines with wavy lines at the ends.

[0079] The present application provides an electronic device that can be applied to various communication systems or communication protocols, such as Bluetooth (BT) communication technology, global positioning system (GPS) communication technology, global system of mobile communication (GSM) communication technology, wireless fidelity (WiFi) communication technology, wideband code division multiple access wireless (WCDMA) communication technology, long term evolution (LTE), 5G communication technology, and other future communication technologies. The electronic device in the embodiment of the present application can be a mobile phone, a tablet computer (pad), a laptop computer, a smart home, a smart wearable device (e.g., a smart watch, a smart bracelet, smart glasses, a smart helmet), a virtual reality (VR) electronic device, an augmented reality (AR) electronic device, etc. The electronic device can also be a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, an in-vehicle device, an electronic device in a 5G network, or an electronic device in a future public land mobile network (PLMN), etc., and the present application embodiment is not limited to this.

[0080] In some embodiments of the present application, as shown in Figure 1, the electronic device 01 may include a display screen 10 and a processor 11. The display screen 10 may be electrically connected to the processor 11. The processor 11 may include one or more processing units, for example: the processor 11 may include an application processor (AP), a modem processor, a graphics processor (GPU), an image signal processor (ISP), a controller, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural-network processing unit (NPU), etc. Among them, different processing units may be independent devices or integrated into one or more processors. The above-mentioned processor 11 can be used to control the display screen 10 to display images.

[0081] In addition, the electronic device 01 may further include an external memory interface electrically connected to the processor 11, an internal memory, a universal serial bus (USB) interface, a charging management module, a power management module, a battery, an antenna, a mobile communication module, a wireless communication module, an audio module, a speaker, a receiver, a microphone, an earphone interface, a sensor module, buttons, and a camera. The sensor module may include a pressure sensor, a gyroscope sensor, an air pressure sensor, a magnetic sensor, an acceleration sensor, a distance sensor, a proximity light sensor, a fingerprint sensor, a temperature sensor, a touch sensor, an ambient light sensor, and a bone conduction sensor.

[0082] For example, the display screen 10 may be a micro (or mini) LED display screen (referred to as an MD display screen), or an organic light emitting diode (OLED) display screen.

[0083] In some embodiments of the present application, as shown in FIG2A , the display screen 10 may include a plurality of light-emitting diode chips (hereinafter referred to as LED chips) 20. The LED chip 20 may emit monochromatic light, such as red (red, R) light, green (green, G) light, or blue (blue, B) light among the three primary colors of light. In this case, the LED chip 20 may include a light-emitting device 201 as shown in FIG2B (a top view obtained along the direction A in FIG2A ), and the light-emitting device 201 is used to emit the above-mentioned monochromatic light. In this case, the area where three adjacent LED chips 20 respectively used to emit the three primary colors of light are located can be used as a pixel (pixel, P) of the display screen 10, and the area where each LED chip 20 in the pixel is located can be a sub-pixel.

[0084] Continuing with FIG. 2B , the display screen 10 may include multiple pixels 100, where each pixel 100 is located. Multiple LED chips 20 may be arranged in an array, with at least three adjacent LED chips 20 emitting light of the three primary colors located within the same pixel 100. This allows the display screen 10 with multiple LED chips 20 to achieve color display.

[0085] For example, when the display screen 10 is a micro or mini LED display screen, the LED chip 20 may be a micro LED chip, which is typically smaller than 50 μm in size. Alternatively, the LED chip 20 may be a mini LED chip, which is typically between 50 μm and 200 μm in size.

[0086] Alternatively, in other embodiments of the present application, as shown in FIG3A , the display screen 10 may include only one LED chip 20. The LED chip 20 may emit the aforementioned R light, G light, or B light, or the LED chip 20 may also emit a mixture of the aforementioned R light, G light, or B light. In this case, as shown in FIG3B (a top view taken along the direction B in FIG3A ), the LED chip 20 may include a plurality of light-emitting devices 201 arranged in an array, and the light-emitting devices 201 are configured to emit the aforementioned monochromatic light.

[0087] In this case, the area containing the at least three adjacent light-emitting devices 201 that respectively emit light of the three primary colors can be located within the same pixel 100. The area containing the three adjacent light-emitting devices 201 that respectively emit light of the three primary colors can serve as a pixel of the display screen 10, and the area containing each light-emitting device 201 in the pixel can serve as a sub-pixel. In this way, the display screen 10, which is primarily composed of a single LED chip 20, can achieve color display.

[0088] Alternatively, in some other embodiments of the present application, one LED chip 20 shown in FIG. 3B may include at least two light-emitting devices 201 for emitting light of the same color.

[0089] 2B and 3B illustrate the pixel arrangement of the display screen 10 by arranging the R, G, and B subpixels in the same pixel in the same row. The arrangement of the R, G, and B subpixels can be determined based on the display effect, pixel density (pixels per inch, PPI), resolution, and other parameters, and is not limited in this application. For example, the pixel arrangement of the display screen 10 can also be a Pentile pixel arrangement (also called a P arrangement), a Delta pixel arrangement (also called a D arrangement), or a Diamond arrangement.

[0090] The following describes in detail the structure and manufacturing method of the LED chip 20 provided in the embodiments of the present application through specific examples. In some embodiments of the present application, as shown in Figure 4 (a cross-sectional view obtained by cutting along the dotted line O1-O2 in Figure 3B), the LED chip 20 may include a driver backplane 200, and the light-emitting device 201 may be disposed on the driver backplane 200 through a monolithic integration process or a mass transfer process and electrically connected to the driver backplane 200. The driver backplane 200 can drive the light-emitting device 201 to emit light.

[0091] For example, the driving backplane 200 may include a plurality of pixel driving circuits arranged in an array (not shown in the figure). Among them, one pixel driving circuit may be provided in one of the above-mentioned sub-pixels, and the pixel driving circuit may drive the light-emitting device 201 located in the same sub-pixel to emit light. A pixel driving circuit may include a plurality of transistors and at least one capacitor. The above-mentioned transistor may be a thin film transistor (TFT) or a metal-oxide-semiconductor field effect transistor (MOSFET). Among them, the above-mentioned field effect transistor may include at least one of an N-type metal oxide semiconductor transistor (negative channel metal oxide semiconductor, NMOS), a P-type metal oxide semiconductor transistor (positive channel-metal-oxide-semiconductor, PMOS) and a complementary metal oxide semiconductor transistor (complementary metal oxide semiconductor, CMOS). The above is an example of the structure of the pixel driving circuit and does not constitute a limitation on the structure of the pixel driving circuit.

[0092] Continuing with FIG4 , the light-emitting device 201 may include a light-emitting layer 2011. For example, if the LED chip 20 is a micro (or mini) LED chip, the light-emitting device 201 may be a micro (or mini) LED light-emitting device. In this case, the light-emitting layer 2011 of the light-emitting device 201 may be a semiconductor active layer, which may also be referred to as a multiple quantum well (MQW) layer. The material of the MQW layer may include indium gallium nitride (InGaN).

[0093] Based on this, the light-emitting device 201 may further include a first electrode 211, a second electrode 212, and a first semiconductor layer 2012 and a second semiconductor layer 2013 as shown in FIG5A . The first semiconductor layer 2012 may be electrically connected to the first electrode 211, and the second semiconductor layer 2013 may be electrically connected to the second electrode 212. The first semiconductor layer 2012 and the second semiconductor layer 2013 may be located on either side of the light-emitting layer 2011. For example, the first semiconductor layer 2012 is stacked on the light-emitting layer 2011, and the second semiconductor layer 2013 is stacked on a side of the light-emitting layer 2011 facing away from the first semiconductor layer 2012. Furthermore, the first electrode 211 may be disposed between the first semiconductor layer 2012 and the driving backplane 200, and the first electrode 211 may be electrically connected to the driving backplane 200. The second electrode 212 may be disposed on a side of the second semiconductor layer 2013 facing away from the light-emitting layer 2011, and the second electrode 212 may be electrically connected to the driving backplane 200.

[0094] The first semiconductor layer 2012 includes a first semiconductor material and the second semiconductor layer 2013 includes a second semiconductor material. The first semiconductor material and the second semiconductor material may have different doping types. In some embodiments of the present application, as shown in FIG5A , the first semiconductor material may include an N-type doped semiconductor material, such as N-type gallium nitride (GaN), which is represented as N-GaN in the figure. The second semiconductor material may include a P-type doped semiconductor material, such as P-type GaN, which is represented as P-GaN in the figure.

[0095] In this case, the first semiconductor material of the first semiconductor layer 2012 can be N-type doped in a pure semiconductor material (i.e., an intrinsic semiconductor material), for example, by doping with a tetravalent element. In the formed first semiconductor layer 2012, free electrons are majority carriers and holes are minority carriers. The pure semiconductor material can be gallium nitride (GaN), and the tetravalent element can be silicon (Si). In this way, the first semiconductor layer 2012 mainly conducts electricity by free electrons. The greater the concentration of the doped element during the N-type doping process, the higher the concentration of majority carriers (free electrons), and the stronger the conductivity of the first semiconductor layer 2012. The first electrode 211 electrically connected to the first semiconductor layer 2012 can also be called an N-electrode.

[0096] The above description of the N-type doping process is based on the example of doping a pure semiconductor material with a tetravalent element. This application does not limit the elements used to achieve N-type doping, as long as the free electrons in the first semiconductor layer 2012 are majority carriers and the holes are minority carriers while the performance of the light-emitting device 201 meets the requirements.

[0097] In addition, as shown in Figure 5A, the second semiconductor material of the second semiconductor layer 2013 can be P-type doped in a pure semiconductor material, for example, by doping with a divalent element. In the formed second semiconductor layer 2013, free holes are majority carriers and free electrons are minority carriers. The pure semiconductor material can be GaN, and the divalent element can be magnesium (Mg). In this way, the second semiconductor layer 2013 is mainly conductive by holes. The greater the concentration of the doped element during the P-type doping process, the higher the concentration of majority carriers (holes), and the stronger the conductivity of the second semiconductor layer 2013. The second electrode 212 coupled to the second semiconductor layer 2013 can also be called a P electrode.

[0098] Similarly, the above description of the P-type doping process uses the example of doping a pure semiconductor material with a divalent element. This application does not limit the elements used to achieve P-type doping, as long as the second semiconductor layer 2013 is filled with holes as the majority carriers and free electrons as the minority carriers while the performance of the light-emitting device 201 meets the requirements.

[0099] Based on this, a PN junction can be formed between the first semiconductor layer 2012 and the second semiconductor layer 2013 shown in FIG5A . The light-emitting layer 2011 is located in the active region of the PN junction. In this case, the driving backplane 200 (as shown in FIG4 ) of the light-emitting device 201 can be electrically connected to the first electrode 211 and the second electrode 212, so that the pixel driving circuit in the driving backplane 200 can provide voltages to the first electrode 211 and the second electrode 212 of the light-emitting device 201, respectively, to form an external electric field. This external electric field can control the current flowing through the light-emitting layer 2011 of the light-emitting device 201, thereby controlling the number of photons excited in the light-emitting layer 2011, thereby achieving the purpose of controlling the brightness of the light-emitting device 201.

[0100] In addition, the first electrode 211 and the second electrode 212 in FIG. 5A can be made of a conductive material. The conductive material may include a conductive metal material. Alternatively, the conductive material may include a transparent conductive material, such as indium tin oxide (ITO) or indium zinc oxide (IZO).

[0101] For example, when the preset light-emitting direction of the light-emitting device 201 is a direction away from the driving backplane 211 (i.e., above the driving backplane 211), the second electrode 212 can be made of a transparent conductive material so that the second electrode 212 has sufficient light transmittance, which is beneficial to improving the light-emitting efficiency of the light-emitting device 201. The first electrode 212 can be made of a conductive metal material, thereby reflecting the portion of the light emitted by the light-emitting layer 2011 that is transmitted in the direction toward the driving backplane 211, so that the light emitted by the light-emitting layer 2011 is generally transmitted in a direction away from the driving backplane 211. Similarly, when the preset light-emitting direction of the light-emitting device 201 is a direction toward the driving backplane 211 (i.e., below the driving backplane 211), the first electrode 212 can be made of a transparent conductive material, and the second electrode 212 can be made of a conductive metal material.

[0102] The above description is based on the example of FIG5A in which the first semiconductor material of the first semiconductor layer 2012 includes N-type GaN, and the second semiconductor material of the second semiconductor layer 2013 includes P-type GaN. In other embodiments of the present application, the second semiconductor material of the second semiconductor layer 2013 may include N-type GaN, and the first semiconductor material of the first semiconductor layer 2012 may include P-type GaN. The doping process of the first semiconductor layer 2012 and the second semiconductor layer 2013 is the same as described above and will not be further described here.

[0103] Alternatively, as another example, when the LED chip 20 shown in FIG4 is an OLED chip, the light-emitting device 201 can be an OLED light-emitting device. In this case, the light-emitting layer 2011 of the light-emitting device 201 can be an organic light-emitting layer (EML) mainly composed of an organic light-emitting material, such as an organic fluorescent material or an organic phosphorescent material. Based on this, the light-emitting device 201 can also include a first electrode 211, a second electrode 212, a hole injection layer (HIL) 2014, a hole transport layer (HTL) 2015, an electron transport layer (ETL) 2016, and an electron injection layer (EIL) 2017 as shown in FIG5B. For example, the first electrode 211 can be an anode, and the second electrode 212 can be a cathode.

[0104] In this case, the pixel driving circuit in the driving backplane 200 (as shown in FIG4 ) of the light-emitting device 201 can provide voltages to the first electrode 211 and the second electrode 212 of the light-emitting device 201 shown in FIG5B , respectively, to form an external electric field. The external electric field can cause the first electrode 211 to generate holes and inject them into the hole injection layer 2014, and the second electrode 212 to generate electrons and inject them into the electron injection layer 2017. In addition, under the action of the hole transport layer 2015 and the electron transport layer 2016, the above-mentioned holes and electrons migrate to the light-emitting layer 2011, and the electrons and holes that meet in the light-emitting layer 2011 generate energy excitons in the light-emitting layer 2011, thereby exciting the light-emitting molecules in the light-emitting layer 2011 to emit light. Among them, the materials of the first electrode 211 and the second electrode 212 shown in FIG5B are the same as those described above and will not be repeated here.

[0105] Alternatively, in other embodiments of the present application, the light-emitting layer 2011 may also be an inorganic fluorescent or phosphorescent material. The above is an example of the structure of the light-emitting device 201 and does not constitute a limitation on the structure of the light-emitting device 201. For convenience of description, the following description is based on the light-emitting device 201 having the structure shown in Figure 5A as an example.

[0106] On this basis, in some embodiments of the present application, as shown in FIG6 , the LED chip 20 may further include a cover layer 202 covering the light-emitting layer 2011. When the LED chip 20 includes a driver backplane 200, the cover layer 202 may be disposed on the side of the LED chip 20 facing away from the driver backplane 200. For example, when the light-emitting device 201 is a micro (or mini) LED light-emitting device as shown in FIG5A , the light-emitting device 201 may include a first semiconductor layer 2012 and a second semiconductor layer 2013 as shown in FIG6 . In this case, the cover layer 202 may be disposed on the side of the second semiconductor layer 2013 facing away from the light-emitting layer 2011.

[0107] In some embodiments of the present application, as further shown in FIG6 , the cover layer 202 may include a substrate layer 2021 and a nano-pillar array structure 2022. The nano-pillar array structure 2022 may be disposed within the substrate layer 2021, which may be used to support the nano-pillar array structure 2022. For example, the nano-pillar array structure 2022 may include a plurality of spaced nano-pillars 2023. Furthermore, as further shown in FIG6 , the extension direction (Z direction) of the nano-pillars 2023 may be perpendicular to the driving backplane 200. Accordingly, the end of the nano-pillars 2023 facing away from the light-emitting layer 2011 may penetrate the upper surface of the substrate layer 2021 (the surface facing away from the light-emitting layer 2011). The end of the nano-pillars 2023 facing the light-emitting layer 2011 may penetrate the lower surface of the substrate layer 2021 (the surface facing the light-emitting layer 2011), or may not penetrate the lower surface of the substrate layer 2021; this is not limited in this application.

[0108] The extension direction of the nano-microcolumns 2023 being perpendicular to the driving backplane 200 means that the surface of the driving backplane 200 facing the light-emitting device 201 can be approximated as a plane, and the extension direction of the nano-microcolumns 2023 is perpendicular to the surface of the driving backplane 200 facing the light-emitting device 201.

[0109] For example, when the nanopillars 2023 are cylindrical, the diameter of the nanopillars 2023 can be between 10 nm and 1000 nm. Specifically, the diameter of the nanopillars 2023 can be set based on the size of the subpixels in the display screen 10. If the number of nanopillars 2023 in a subpixel is constant, a nanopillar 2023 with a larger diameter can be used for a larger subpixel area, while a nanopillar 2023 with a smaller diameter can be used for a smaller subpixel area. For example, if the vertical projection of a subpixel in the display screen 10 on the driver backplane 200 is circular, and the diameter of the vertical projection of the subpixel in the display screen 10 on the driver backplane 200 is 2 μm, the diameter of the nanopillar 2023 in the subpixel can be 100 nm.

[0110] 6 , the vertical projection of the light-emitting layer 2011 on the cover layer 202 is located within the cover layer 202. This allows the entire cover layer 202 to completely or substantially cover the light-emitting layer 2011, thereby allowing the portion of light emitted by the light-emitting layer 2011 that is directed toward the cover layer 202 to pass entirely or substantially entirely through the cover layer 202 before exiting.

[0111] On this basis, in some embodiments of the present application, as shown in FIG7A (along the direction C in FIG6 ), the material used for the nano-micropillars 2023 includes a color conversion material (represented in black). The refractive index n1 of the color conversion material can be greater than the refractive index n2 of the material used for the substrate layer 2021 (i.e., n1>n2). The nano-micropillars 2023 are an optically denser medium relative to the substrate layer 2021. For example, when the refractive index of the color conversion material is approximately 2, the material used for the substrate layer 2021 can be a low-refractive-index material with a refractive index less than 2, for example, a refractive index of 1.4 to 1.6. For example, the material used for the substrate layer 2021 can include at least one of silicon monoxide (SiO), silicon dioxide (SiO2), and aluminum oxide (Al2O3).

[0112] The color conversion material can convert the color of light emitted by the light-emitting device 201, allowing the sub-pixel where the light-emitting device 201 is located to emit a predetermined light color. For example, when the predetermined light color of the sub-pixel where the light-emitting device 201 is located is R light or G light, the initial light emitted by the light-emitting layer 2011 of the light-emitting device 201 can be B light. Upon receiving the B light emitted by the light-emitting layer 2011, the color conversion material in the cover layer 202 can convert the B light into R light or G light. The color conversion material used to convert B light into R light and the color conversion material used to convert B light into G light can have different parameters, such as composition and thickness. The above description uses the example of the initial light being B light and the color conversion material converting B light into R light and G light. This application does not limit the colors of the initial light and the light converted by the color conversion material, as long as the initial light and the light converted by the color conversion material are consistent with the three primary colors.

[0113] For example, the color conversion material may be a quantum dot (QD) material. The quantum dot material may include at least one of CdSe (cadmium selenide), CdS (cadmium sulfide), ZnSe (zinc selenide), ZnS (zinc sulfide), InP (indium phosphide), CdTe (cadmium telluride), ZnTe (zinc telluride), and AgInGaS (silver indium gallium sulfide). Alternatively, the color conversion material may include a fluorescent or phosphorescent material.

[0114] In this case, as shown in FIG7B (a cross-sectional view taken along the dashed line Q1-Q2 in FIG7A ), when the initial light emitted by the light-emitting device 201, such as light B, is incident on the nano-pillars 2023, at least a portion of the light incident on the interface between the nano-pillars 2023 and the substrate layer 2021 is totally reflected, allowing the totally reflected light to continue to propagate within the nano-pillars 2023. This increases the optical path length of the light emitted by the light-emitting device 201 within the nano-pillars 2023, thereby increasing the duration of interaction between the light and the color conversion material within the nano-pillars 2023. This allows more initial light (such as light B) to be converted into R light (or G light) by the color conversion material, thereby improving the efficiency of color conversion.

[0115] Based on this, in order to cause total internal reflection of light incident on the interface between the nano-pillars 2023 and the substrate layer 2021, if the material used in the nano-pillars 2023 includes a color conversion material, at least the material of the portion of the nano-pillars 2023 that contacts the substrate layer 2021 can be the color conversion material. That is, the material used to form the interface between the nano-pillars 2023 and the substrate layer 2021 can be the color conversion material, and this application does not limit the material of the remaining portions of the nano-pillars 2023. In this case, for example, the material used in the substrate layer 2021 can include at least one of the aforementioned SiO, SiO2, and Al2O3.

[0116] On this basis, in some embodiments of the application, as shown in FIG7A , when the material used for nanopillars 2023 includes a color conversion material (represented in black), the height H1 of nanopillars 2023 can be 0.1 μm to 10 μm. In this case, when the height H1 of nanopillars 2023 is less than 0.1 μm, the height H1 of nanopillars 2023 is too small, and the initial light incident on light-emitting device 201 (e.g., light B) has a short optical path when passing through nanopillars 2023. The interaction time with the color conversion material in nanopillars 2023 is short, resulting in a large amount of initial light (e.g., light B) not being converted into the predetermined light (e.g., light R and light G), thereby reducing the color conversion efficiency.

[0117] Alternatively, when the height H1 of the nano-pillar 2023 is greater than 10 μm, the height H1 of the nano-pillar 2023 is too large, and the initial light incident on the light-emitting device 201 (for example, B light) has a long optical path when passing through the nano-pillar 2023, and the interaction time with the color conversion material in the nano-pillar 2023 is long, resulting in the preset light (for example, R light and G light) that has been converted by the color conversion material still being transmitted in the nano-pillar 2023, causing part of the light to be absorbed by the nano-pillar 2023, resulting in light loss, thereby reducing the luminous efficiency of the LED light-emitting chip 20.

[0118] Therefore, when the height H1 of the nanopillars 2023 is between 0.1 μm and 10 μm, the conversion efficiency of the initial light (e.g., B light) incident on the light-emitting device 201 in the nanopillars 2023 can be improved, while the probability of light loss of the predetermined light (e.g., R light and G light) converted by the color conversion material can be reduced, thereby improving the luminous efficiency of the LED light-emitting chip 20. For example, the height H1 of the nanopillars 2023 can be 0.1 μm, 1 μm, 3 μm, 5 μm, 7 μm, or 10 μm. In some embodiments of the present application, when the height H1 of the nanopillars 2023 is approximately 2 μm, the color conversion efficiency of the LED chip 20 can reach approximately 80%.

[0119] Alternatively, in other embodiments of the present application, as shown in FIG8A (along the direction C in FIG6 ), the material used for substrate layer 2021 may include a color conversion material (represented in black). Accordingly, the refractive index n1 of the color conversion material may be greater than the refractive index n3 of the nanopillars 2023 (i.e., n1>n3), and substrate layer 2021 may be an optically denser medium relative to the nanopillars 2023. For example, if the refractive index of the color conversion material is approximately 2, the material used for nanopillars 2023 may be a low-refractive-index material with a refractive index less than 2, for example, a refractive index of 1.4 to 1.6. For example, the material used for nanopillars 2023 may include at least one of SiO, SiO2, and Al2O3.

[0120] Similarly, as shown in FIG8B (a cross-sectional view taken along dashed line Q3-Q4 in FIG8A ), when the initial light emitted by the light-emitting device 201, such as light B, is incident on the substrate layer 2021, at least a portion of the light incident on the interface between the substrate layer 2021 and the nanopillars 2023 is totally reflected, allowing the totally reflected light to continue to propagate within the substrate layer 2021. This increases the optical path length of the light emitted by the light-emitting device 201 within the substrate layer 2021, thereby increasing the duration of interaction between the light and the color conversion material within the substrate layer 2021. This allows more of the initial light (e.g., light B) to be converted into R light (or G light) by the color conversion material, thereby improving the efficiency of color conversion.

[0121] Similarly, in order to achieve total internal reflection of light incident on the interface between substrate layer 2021 and nanopillars 2023, if the material used for substrate layer 2021 includes a color conversion material, at least the portion of substrate layer 2021 that encapsulates the nanopillars 2023 can be made of the color conversion material. That is, the material used to form the interface between substrate layer 2021 and nanopillars 2023 can be the color conversion material, and this application does not limit the material of the remaining portion of substrate layer 2021. In this case, for example, the material used for nanopillars 2023 can include at least one of the aforementioned SiO, SiO2, and Al2O3.

[0122] Based on this, in some embodiments of the present application, as shown in FIG8A , when the material used for the substrate layer 2021 includes a color conversion material (represented by black), the thickness D1 of the substrate layer 2021 can be 0.1 μm to 10 μm. Similarly, when the thickness D1 of the substrate layer 2021 is 0.1 μm to 10 μm, the conversion efficiency of the initial light (e.g., B light) incident on the light-emitting device 201 in the substrate layer 2021 can be improved, while also reducing the probability of light loss of the predetermined light (e.g., R light and G light) converted by the color conversion material, thereby improving the luminous efficiency of the LED chip 20. For example, the thickness D1 of the substrate layer 2021 can be 0.1 μm, 1 μm, 3 μm, 5 μm, 7 μm, or 10 μm. In some embodiments of the present application, when the thickness D1 of the substrate layer 2021 is approximately 2 μm, the color conversion efficiency of the LED chip 20 can reach approximately 80%.

[0123] In summary, as shown in FIG6 , the LED chip 20 provided in the embodiment of the present application includes a light-emitting device 201 and a cover layer 202 covering the light-emitting layer 2011 of the light-emitting device 201. The cover layer 202 includes a substrate layer 2021 and a plurality of nano-pillars 2023 disposed in the substrate layer 2021. The material used for the nano-pillars 2023 may include a color conversion material, and the refractive index n1 of the color conversion material may be greater than the refractive index n2 of the material used for the substrate layer 2021. Alternatively, the material used for the substrate layer 2021 may include a color conversion material, and the refractive index n1 of the color conversion material may be greater than the refractive index n3 of the material used for the nano-pillars 2023.

[0124] In this way, on the one hand, the nano-pillars 2023 or the substrate layer 2021 containing the color conversion material in the LED chip 20 can convert the initial light from the light-emitting device 201, such as B light, into the desired light, such as R light. This can avoid the problem of limited luminous efficiency or color shift in the red LED chip 20 when using AlInGaP or InGaN to manufacture the red light-emitting LED chip 20, thereby alleviating the problem that the red micro-LED chip affects the quality of the entire micro-LED display.

[0125] On the other hand, the structure primarily composed of the color-conversion material, such as nanopillars 2023, is an optically denser medium relative to surrounding components, such as substrate layer 2021. Alternatively, the structure primarily composed of the color-conversion material, such as substrate layer 2021, is an optically denser medium relative to surrounding components, such as nanopillars 2023. This allows at least a portion of the light incident on the interface between the optically denser medium and the optically sparser medium to undergo total internal reflection. This totally reflected light can then continue to propagate within the structure composed of the color-conversion material (nanopillars 2023 or substrate layer 2021). This increases the optical path length of the initial light emitted by the light-emitting device 201 within the color-conversion material and the duration of its interaction with the color-conversion material, thereby improving color conversion efficiency, such as red light, while reducing the probability of the initial light emitted by the light-emitting device 201 leaking B light from the light-emitting side of the LED chip 20.

[0126] In comparison, in the related art shown in FIG9 , a color conversion layer 02 composed entirely of color conversion material covers the light-emitting side of the light-emitting device 201. Light B emitted by the light-emitting device 201 passes from bottom to top through the color conversion layer 02. As a result, a portion of the B light emitted by the light-emitting device 201 is converted into R light by the color conversion layer 02. However, a portion of the B light, due to its shorter optical path and transmission time in the color conversion layer 02, is unable to fully interact with the color conversion material in the color conversion layer 02. Consequently, this portion of the B light is not converted into R light and is emitted, resulting in B light leakage from the light-emitting side of the device.

[0127] On the other hand, as can be seen from the above, in the embodiment of the present application, as shown in Figure 6, the above-mentioned covering layer 202 includes a substrate layer 2021 and a plurality of nano-pillars 2023. When the material used for the nano-pillars 2023 is a color conversion material, the substrate layer 2021 can wrap or encapsulate the sides of the nano-pillars 2023, reducing the probability of direct contact between the color conversion material and external water, oxygen, and impurities. Similarly, when the material used for the substrate layer 2021 is a color conversion material, the plurality of nano-pillars 2023 can wrap or encapsulate part of the side of the substrate layer 2021, reducing the probability of direct contact between the color conversion material and external water, oxygen, and impurities. In this way, the packaging performance of the entire LED chip 20 can be improved, the service life of the color conversion material can be increased, and the attenuation rate of the color conversion material under blue light irradiation can be reduced.

[0128] On the other hand, the cover layer 202 of the LED chip 20 provided in the embodiment of the present application includes a plurality of nano-pillars 2023, thereby enabling the cover layer 202, primarily composed of the substrate layer 2021 and the plurality of nano-pillars 2023, to be a non-uniform medium. As a result, when light emitted by the light-emitting device 201 propagates through the cover layer 202, it is scattered by the nano-pillars 2023, thereby increasing the probability of the light re-entering the color conversion material, thereby improving color conversion efficiency, for example, red light.

[0129] On this basis, when the electronic device 01 shown in FIG1 is the above-mentioned VR or AR electronic device, such as VR or AR glasses, the display screen 10 of the electronic device 01 can be set on the frame of the VR or AR glasses, but the user can see the picture displayed on the display screen 10 at the location of the lens. Therefore, the above-mentioned electronic device 01 may include a light-guiding structure (not shown in the figure) for projecting the light emitted by the LED chip 20 to the location of the lens. In this case, in order to make all or nearly all of the light emitted by the LED chip 20 enter the light-guiding structure, it is necessary to reduce the light emission angle of the LED chip 20, thereby improving the utilization rate of the light emitted by the LED chip 20.

[0130] In addition, the size of the display screen 10 in the VR or AR electronic device is relatively small, so in some embodiments of the present application, the display screen 10 can adopt the structure shown in Figure 3A, that is, the display screen 10 can only include one LED chip 20 capable of full-color display. Based on this, as shown in Figure 3B, an LED chip 20 can include multiple light-emitting devices 201, and the light-emitting layer 2011 of each light-emitting device 201 can be covered with a covering layer 202 as shown in Figure 6. As can be seen from the above, the covering layer 202 can include a nano-micro-pillar array structure 2022. Therefore, a nano-micro-pillar array structure 2022 can be set above the light-emitting layer 2011 of a light-emitting device 201. Based on this, in order to reduce the light emission angle of the LED chip 20, the multiple nano-micro-pillars 2023 in the nano-micro-pillar array structure 2022 shown in Figure 6 can be arranged periodically.

[0131] In some embodiments of the present application, to enable a periodic arrangement of multiple nano-pillars 2023 within a single nano-pillar array structure 2022, the nano-pillar array structure 2022 may have at least two periodic patterns 30, as shown in FIG10A . For example, as shown in FIG10A , the vertical projection of a line connecting the geometric centers of at least two nano-pillars 2023 within the single nano-pillar array structure 2022 onto the light-emitting layer 2011 (as shown in FIG6 ) may form the aforementioned periodic pattern 30 (e.g., represented by a dotted line in FIG10A ). In this case, the multiple nano-pillars 2023 within the single nano-pillar array structure 2022 may be periodically arranged according to the aforementioned periodic pattern 30.

[0132] Furthermore, the spacing P between two adjacent nano-pillars 2023 forming the same periodic pattern 30 can be the same, thereby enabling the orderly arrangement of the multiple nano-pillars 2023 in the same periodic pattern 30, and further enabling the periodic and orderly arrangement of the multiple nano-pillars 2023 in the same nano-pillar array structure 2022. For example, the periodic and orderly arrangement of the multiple nano-pillars 2023 in the same nano-pillar array structure 2022 can be similar to the periodic arrangement of a photonic crystal microstructure.

[0133] In this way, since the multiple nano-pillars 2023 in the nano-pillar array structure 2022 of the LED chip 20 can be arranged in a periodic and orderly manner, when the material used for the nano-pillars 2023 is a color conversion material, the light emission directions of the converted light (R light or G light) emitted by each nano-pillar 2023 can be consistent or approximately consistent, achieving the effect of collimating the emitted light, thereby reducing the light emission angle of the LED chip 20. Alternatively, when the material used for the substrate layer 2021 (as shown in Figure 6) is a color conversion material, the light emission directions of the converted light (R light or G light) emitted by the substrate layer 2021 located between the multiple periodically and orderly arranged nano-pillars 2023 are consistent or approximately consistent, achieving the effect of collimating the emitted light, thereby reducing the light emission angle of the LED chip 20.

[0134] The vertical projection of the line connecting the geometric centers of at least two nano-pillars 2023 onto the light-emitting layer 2011 (as shown in FIG6 ) can be the vertical projection of the line connecting the geometric centers of at least two nano-pillars 2023 onto the plane where the light-emitting layer 2011 resides. Specifically, the light-emitting layer 2011 can be approximately considered as a film layer without thickness, and the plane where the film layer resides is the plane where the light-emitting layer 2011 resides. Alternatively, the surface of the light-emitting layer 2011 facing the cover layer 202 can be approximately considered as a horizontal plane, and the plane where the surface resides can be the plane where the light-emitting layer 2011 resides. In addition, the geometric center can refer to the projection of the nano-pillars 2023 on the plane where the light-emitting layer 2011 resides as a regular shape or a near-regular shape. The center position of the regular shape can be referred to as the geometric center. For example, when the projection of the nano-pillars 2023 on the plane where the light-emitting layer 2011 resides is a circle, the geometric center of the nano-pillars 2023 can be the center of the circle.

[0135] FIG10A illustrates an example in which the periodic pattern 30 of a nano-pillar array structure 2022 of an LED chip 20 is circular, and the nano-pillar array structure 2022 has three periodic patterns 30. Alternatively, as another example, the periodic pattern 30 of a nano-pillar array structure 2022 of an LED chip 20 can be a regular polygon, such as a regular hexagon, as shown in FIG10B . Alternatively, the periodic pattern 30 can be rectangular or triangular. This application does not limit the shape or number of the periodic pattern 30.

[0136] Furthermore, Figures 10A and 10B illustrate the case where the vertical projection of the nanopillars 2023 on the light-emitting layer 2011 (as shown in Figure 6) is a circle. In other embodiments of the present application, the vertical projection of the nanopillars 2023 on the light-emitting layer 2011 can be a polygon, or at least one of a circle and a polygon. For ease of explanation, the following examples are based on the case where the vertical projection of the nanopillars 2023 on the light-emitting layer 2011 is a circle.

[0137] In this case, as shown in FIG10A or FIG10B , at least two periodic patterns 30 of a nano-micropillar array structure 2022 can be nested in sequence, i.e., one periodic pattern 30 is arranged around the perimeter of another periodic pattern 30. Furthermore, the geometric centers of at least two periodic patterns 30 of the nano-micropillar array structure 2022 overlap. For example, the three circular periodic patterns 30 in FIG10A can be concentric circles.

[0138] Alternatively, for another example, at least two periodic patterns 30 of a nano-micropillar array structure 2022 of an LED chip 20 are arranged in an array. As shown in FIG10C , multiple periodic patterns 30 are arranged in an array in a rectangular shape. Similarly, the spacing P between two adjacent nano-micropillars 2023 constituting the same periodic pattern 30 can be the same. Alternatively, multiple periodic patterns 30 are arranged in an array in a regular polygon, such as a regular hexagon. FIG10C illustrates an example in which the periodic pattern 30 is a rectangle. The periodic pattern 30 can also be at least one of the aforementioned circular, triangular, and other polygonal shapes.

[0139] Figures 10A, 10B, and 10C illustrate an example in which the vertical projection areas of at least two nano-pillars 2023 constituting the same periodic pattern 30 on the light-emitting layer 2011 (as shown in Figure 6) are the same. In other embodiments of the present application, the vertical projection areas of at least two nano-pillars 2023 constituting the same periodic pattern 30 on the light-emitting layer 2011 (as shown in Figure 6) may be different.

[0140] Furthermore, to reduce the light emission angle of the LED chip 20, when the material used for the nanopillars 2023 or the substrate layer 2021 shown in FIG6 includes a color conversion material, the color conversion material may be an optically anisotropy material. For example, as shown in FIG11A , taking the nanopillars 2023 as an example, when the color conversion material includes a quantum dot material, the quantum dot material may be in the form of at least one of a one-dimensional quantum dot material, such as a nanopillar 20231, as shown in FIG11A , a two-dimensional quantum dot material, such as a nanosheet 20232, as shown in FIG11B , or a three-dimensional quantum dot material, such as a nanosphere 20233, as shown in FIG11C .

[0141] Among them, the above-mentioned optical anisotropic material refers to the material whose propagation characteristics of light change with different directions. Optically anisotropic materials can have a dominant light-emitting direction, such as the direction in which the light is strongest or relatively strong. For example, taking the shape of a quantum dot material as shown in Figure 11B, such as a nanosheet 20232 as an example, as shown in Figure 12A, it can be seen from the light-emitting light type of the nanosheet 20232 that the dominant light-emitting direction of the nanosheet 20232 can be along the Z direction in Figure 12A. Based on this, the specific structure of the nanosheet 20232 can be shown in Figure 12B, and it can be seen that the dominant light-emitting direction Z direction of the nanosheet 20232 can be perpendicular to the two-dimensional plane XOY plane where the nanosheet 20232 is located.

[0142] In this case, as shown in Figures 11A, 11B, or 11C, the color-conversion material can be oriented along a first direction (e.g., the Z direction), where the first direction (e.g., the Z direction) can be perpendicular to the light-emitting layer 2011 (as shown in Figure 6). This allows the dominant light-emission direction of the color-conversion material to align with the first direction (e.g., the Z direction), collimating the light emitted from the LED chip 20 and thereby reducing the light emission angle of the LED chip 20. For example, the light emission angle of the LED chip 20 with the color-conversion material arranged in this manner can be tested using an optical instrument. The light emission angle can be less than 65°, for example, approximately 45°. Figures 11A, 11B, and 11C illustrate the orientation distribution of the color-conversion material in the nano-pillars 2023. When the substrate layer 2021 includes the color-conversion material, the orientation distribution of the color-conversion material can be similarly determined and will not be further described here.

[0143] As can be seen from the above, when the electronic device 01 is a VR or AR electronic device, the display screen 10 of the electronic device 01 can adopt the structure shown in Figure 3A, that is, the display screen 10 can include only one LED chip 20 capable of full-color display. Based on this, the structure of the full-color display LED chip 20 can be shown in Figure 13 (a cross-sectional view obtained by cutting along the dotted line O3-O4 in Figure 3B). The LED chip 20 may include a first light-emitting device 201a, a second light-emitting device 201b, a first cover layer 202a, and a second cover layer 202b.

[0144] The first covering layer 202a covers the light-emitting layer 2011 of the first light-emitting device 201a, and the second covering layer 202b covers the light-emitting layer 2011 of the second light-emitting device 201b. The initial light emitted by the first light-emitting device 201a and the second light-emitting device 201b may be B light. The first covering layer 202a and the second covering layer 202b respectively perform color conversion on the initial light emitted by the first light-emitting device 201a and the second light-emitting device 201b, and the converted light is R light and G light, respectively.

[0145] Furthermore, as shown in FIG13 , the LED chip 20 may further include a planar layer 40 and a retaining wall 41. The planar layer 40 may be disposed between the first light-emitting device 201a and the second light-emitting device 201b, and the planar layer 40 may be connected to the first light-emitting device 201a and the second light-emitting device 201b. The retaining wall 41 may be disposed within the planar layer 40 and located between the first light-emitting device 201a and the second light-emitting device 201b. Furthermore, a portion of the planar layer 40 may be provided between the retaining wall 41 and the first light-emitting device 201a, and between the retaining wall 41 and the second light-emitting device 201b. The substrate layer 2021 of the first cover layer 202a and the substrate layer 2021 of the second cover layer 202b may be connected to form an integral structure, covering the retaining wall 41.

[0146] In this case, in order to form the structure shown in FIG13 , as shown in FIG14A , a plurality of light-emitting devices, such as the first light-emitting device 201a and the second light-emitting device 201b, can be firstly arranged on the driving backplane 200 by a monolithic integration process or a mass transfer process, so that the first electrodes 211 of the light-emitting devices are electrically connected to the driving backplane 200 through a bonding process. For example, in the case where the LED chip 20 includes at least two light-emitting devices, the first electrodes 211 of adjacent light-emitting devices (such as the first light-emitting device 201a and the second light-emitting device 201b) can be connected to form an integral structure. In addition, in order to be able to control the brightness of different light-emitting devices separately, the second electrodes 212 of adjacent light-emitting devices can be insulated. For example, there is a gap between the second electrode 212 of the first light-emitting device 201a and the second electrode 212 of the second light-emitting device 201b, so that the second electrodes 212 of the two light-emitting devices are insulated.

[0147] Next, a flat layer 40 as shown in FIG. 14B and retaining walls 41 within the flat layer 40 may be formed between adjacent light-emitting devices (e.g., the first light-emitting device 201a and the second light-emitting device 201b). For example, a via hole may be formed on the prepared flat layer 40 using a photolithography process, and the retaining walls 41 may be formed within the via hole. The photolithography process in the embodiments of the present application may refer to a process that includes film formation, exposure, and development, and utilizes photoresist, a mask, an exposure machine, and the like to form a pattern.

[0148] The surface of the flat layer 40 facing away from the driver backplane 200 can be flush with the surface of the light-emitting devices (e.g., the first light-emitting device 201a and the second light-emitting device 201b) facing away from the driver backplane 200. In addition, the retaining wall 41 can be made of a high-reflectivity material, for example, a metal material with a reflectivity greater than 90%, such as silver (Ag) or aluminum (Al), so as to reflect light emitted by the light-emitting devices and avoid light crosstalk between adjacent light-emitting devices (e.g., the first light-emitting device 201a and the second light-emitting device 201b).

[0149] In some embodiments of the present application, a first covering layer 202a and a second covering layer 202b as shown in FIG13 can be prepared based on the structure shown in FIG14B. For example, a plurality of nano-pillars 2023 or a plurality of nano-holes can be formed on the surface of the second electrode 212 facing away from the driving backplane 200. Next, a color conversion material is filled between the plurality of nano-pillars 2023 to form the aforementioned substrate layer 2021 mainly composed of the color conversion material. Alternatively, a color conversion material is filled into the plurality of nano-holes to form the nano-pillars 2023 mainly composed of the color conversion material. The following describes an example of the method for manufacturing the nano-pillars 2023 and the substrate layer 2021 based on the structure shown in FIG14B.

[0150] In some embodiments of the present application, based on the structure shown in FIG. 14B , a method for preparing the LED chip 20 may be as shown in FIG. 15 , and may include S101 to S104 .

[0151] S101 , preparing a dielectric layer on a side of the light-emitting device facing away from the driving backplane.

[0152] Specifically, as shown in (a) of FIG16 , a dielectric layer 50 can be deposited on a surface of a plurality of light-emitting devices, such as the first light-emitting device 201a and the second light-emitting device 201b, away from the driving backplane 200 by magnetron sputtering, plasma enhanced chemical vapor deposition (PECVD), inductively coupled plasma chemical vapor deposition (ICPCVD), atomic layer deposition (ALD), or the like. The material of the dielectric layer 50 can be a low-refractive-index material having a refractive index of 1.4 to 1.6, such as at least one of SiO, SiO2, and Al2O3. In addition, the thickness of the dielectric layer 50 can be 0.1 μm to 10 μm. For example, the thickness of the dielectric layer 50 can be 1 μm to 3 μm.

[0153] S102 , patterning the dielectric layer to form a plurality of nano-micro pillars or a plurality of nano-micro pores that are periodically and orderly arranged.

[0154] Specifically, in some embodiments of the present application, as shown in FIG16( b ), a mask 51 may be prepared on the surface of the dielectric layer 50 by a photolithography process, a laser direct writing process, an electron beam direct writing process, a nanoimprint process, or an anodic aluminum oxide (AAO) template method. The material of the mask 51 may include a photoresist (PR), a dielectric material, or a metal material.

[0155] Next, as shown in (c) of FIG16 , an inductively coupled plasma (ICP) process is used to etch the portion of the dielectric layer 50 that is not covered by the mask plate 51. By setting the pattern of the hollowed-out area of ​​the mask plate 51, a plurality of periodically orderly arranged nanopores 501 or periodically orderly arranged nanopillars 2023 as shown in FIG18 can be etched on the dielectric layer 50. The periodic orderly arrangement of the nanopores 501 and the nanopillars 2023 is the same as described above and will not be repeated here. In addition, the shape of the vertical projection of the nanopores 501 and the nanopillars 2023 on the driving backplane 200 can be at least one of a circle, a triangle and a polygon, as can be seen from the above.

[0156] Alternatively, in other embodiments of the present application, the material of the dielectric layer 50 shown in (a) of FIG. 16 may be metal aluminum (Al). For example, in the process of performing the above-mentioned S101, the dielectric layer 50 may be prepared by processes such as electron beam (ebeam), metal magnetron sputtering, or thermal evaporation. Based on this, as shown in (a) of FIG. 17 , a photoresist may be spin-coated on the surface of the prepared dielectric layer 50 away from the driving backplane 200, and a photoresist mask 51 may be manufactured by an alignment photolithography process, a laser direct writing process, or an electron beam direct writing process. The shielding portion of the mask 51 may cover the upper surface of the retaining wall 41, and the hollow portion of the mask 51 is used to expose the light-emitting device (for example, the first light-emitting device 201a and the second light-emitting device 201b).

[0157] Next, an electrochemical process, such as AAO, can be used to place the structure shown in (a) in Figure 17 in an electrolyte mainly composed of at least one of oxalic acid, phosphoric acid or nitric acid. In addition, a dielectric layer 50 made of metal Al is used as the positive electrode, an external metal platinum (Pt) electrode is used as the negative electrode, a voltage is applied to the positive and negative electrodes, and the dielectric layer 50 is subjected to an anodic oxidation reaction using a constant voltage or constant current method. Because the arrangement of aluminum atoms in metal Al is very orderly. Each atom can be adjacent to the six atoms around it to form a hexagonal structure, and a plurality of periodically ordered nanopores 501 can be formed by utilizing the high and low potential difference of metal Al.

[0158] As can be seen from the above, when dielectric layer 50 is an aluminum metal layer, the regular arrangement of aluminum atoms allows the electrochemical process to form periodically ordered nanopores 501. In comparison, in related art, when nanopores 501 are formed using the electrochemical process on a dielectric layer composed of a semiconductor material such as GaN, the irregularly distributed defects within the GaN affect the formation of the nanopores, resulting in the inability to form periodically ordered nanopores.

[0159] In summary, in the embodiments of the present application, the nanopore 501 can be formed on the dielectric layer 50 by using a photolithography process, a laser direct writing process, an electron beam direct writing process, a nanoimprint process, or an electrochemical process (e.g., an AAO process). Specifically, when the nanopore 501 has a small aspect ratio, the nanopore 501 can be formed by using a photolithography process, a laser direct writing process, an electron beam direct writing process, or a nanoimprint process. When the nanopore 501 has a large aspect ratio, the nanopore 501 can be formed by using an electrochemical process (e.g., an AAO process).

[0160] S103 , filling a color conversion material between the plurality of nano-pillars or in the plurality of nano-pores to form a covering layer.

[0161] Specifically, the mask plate 51 shown in FIG. 16( c ) or the mask plate 51 shown in FIG. 17( b ) is removed to form the structure shown in FIG. 16( d ). Next, in some embodiments of the present application, the multiple nanopores 501 shown in FIG. 16( d ) (or, as shown in FIG. 17( b )) can be filled with a color conversion material by electrophoresis or spin coating, thereby forming multiple nano-pillars 2023 as shown in FIG. 18 . In this case, the material of the nano-pillars 2023 includes the filled color conversion material. Based on this, the dielectric layer 50 shown in FIG. 16( d ) can serve as the substrate layer 2021 in FIG. 18 , thereby forming a first covering layer 202a covering the light-emitting layer 2011 of the first light-emitting device 201a shown in FIG. 18 , and a second covering layer 202b covering the light-emitting layer 2011 of the second light-emitting device 201b shown in FIG.

[0162] Among them, when the color conversion material is the above-mentioned quantum dot material, and the shape of the quantum dot material is a nanocolumn 20231 as shown in Figure 11A, or a nanosheet 20232 as shown in Figure 11B, or at least one of the nanospheres 20233 as shown in Figure 11C, the above-mentioned color conversion material can be oriented and distributed in a direction perpendicular to the driving backplane 200, so that the dominant light-emitting direction of the color conversion material is the main light-emitting direction of the LED chip 20, thereby achieving the purpose of light collimation.

[0163] Furthermore, during the filling process of the color conversion material, the filling depth can be determined based on the absorption coefficient of the color conversion material to ensure that B light does not leak. For example, the greater the absorption coefficient of the color conversion material, the shallower the filling depth, and the lower the B light leakage rate. For example, the height of the nanopillars 2023 can be 0.1μm to 10μm, for example, 1μm to 3μm. This can reduce B light leakage while preventing the converted light (e.g., G light or R light) from being repeatedly absorbed by the color conversion material, thereby improving color conversion efficiency.

[0164] Alternatively, in other embodiments of the present application, when the dielectric layer 50 is patterned using the mask 51 shown in FIG. 16( c ) to form the periodically ordered arrangement of nano-pillars 2023 as shown in FIG. 18 , the color conversion material can be filled between the plurality of nano-pillars 2023 by spin coating or electrophoresis to form the substrate layer 2021 in FIG. 18 , thereby forming a first covering layer 202a covering the light-emitting layer 2011 of the first light-emitting device 201a and a second covering layer 202b covering the light-emitting layer 2011 of the second light-emitting device 201b. Therefore, the material of the substrate layer 2021 includes the color conversion material.

[0165] Similarly, during the filling process of the color conversion material, the filling depth can be determined according to the absorption coefficient of the color conversion material. The thickness of the substrate layer 2021 can be 0.1 μm to 10 μm, for example, 1 μm to 3 μm. The technical effects of this size range are the same as those described above and will not be repeated here.

[0166] S104 , forming an encapsulation layer on a surface of the cover layer facing away from the light-emitting device.

[0167] Specifically, as shown in FIG18 , an encapsulation layer 60 is formed on a surface of a cover layer, such as a first cover layer 202a and a second cover layer 202b, on a side facing away from the driving backplane 200 by a spin coating process, an ALD process, an electron beam (ebeam) process, a PECVD process, or a magnetron sputtering process. The encapsulation layer 60 may include at least one of an organic encapsulation film layer and an inorganic encapsulation film layer.

[0168] For example, the above-mentioned organic encapsulation film layer may include at least one organic material selected from photosensitive (ultraviolet, UV) glue, resin, or polymethyl methacrylate (PMMA). The above-mentioned inorganic encapsulation film layer may include at least one inorganic material selected from SiO2, Al2O3, TiO2 (titanium dioxide), or Si3N4 (silicon nitride). The above-mentioned organic encapsulation film layer and the inorganic encapsulation film layer may be alternately stacked. Since the organic encapsulation film layer can play a buffering role, the inorganic encapsulation film layer is used to block external water and oxygen. For example, the thickness of the above-mentioned encapsulation layer 60 may be 100nm-2000nm. While being able to effectively encapsulate within this size range, it avoids the device being thick, which is not conducive to the design trend of product miniaturization.

[0169] In addition, the method for manufacturing the LED chip 20 may further include manufacturing optical devices, such as micro lenses and distributed Bragg reflectors (DBRs), on the side of the packaging layer 60 facing away from the driver backplane 200. One of the micro lenses may correspond to the position of one sub-pixel in the LED chip 20.

[0170] The above is an example of an LED chip 20 including a flat layer 40 as shown in FIG18 , illustrating the structure and manufacturing method of the LED chip 20. In other embodiments of the present application, the flat layer 40 may not be required in the LED chip 20. In this case, as shown in FIG19 , the LED chip 20 may include multiple light-emitting devices, such as a first light-emitting device 201a and a second light-emitting device 201b, and multiple cover layers, such as a first cover layer 202a and a second cover layer 202b. Furthermore, the LED chip 20 also includes a retaining wall 41. The retaining wall 41 may be disposed between the multiple light-emitting devices, such as the first light-emitting device 201a and the second light-emitting device 201b, and between the multiple cover layers, such as the first cover layer 202a and the second cover layer 202b. The retaining wall 41 may be connected to the first light-emitting device 201a, the second light-emitting device 201b, the substrate layer 2021 of the first cover layer 202a, and the substrate layer 2021 of the second cover layer 202b.

[0171] Based on this, in order to form the structure shown in Figure 19, after a plurality of light-emitting devices are electrically connected to the driving backplane 200 by a monolithic integration process or a mass transfer process as shown in Figure 14A, a retaining wall 41 located between two adjacent light-emitting devices, such as the first light-emitting device 201a and the second light-emitting device 201b, can be made on the driving backplane 200. The material and function of the retaining wall 41 are the same as those described above and will not be repeated here. Next, the above-mentioned photolithography process or electrochemical process can be used to make a covering layer covering the light-emitting layers 2011 of different light-emitting devices, such as a first covering layer 202a and a second covering layer 202b, in the area enclosed by the retaining wall 41. The preparation method of the substrate layer 2021 and the nano-microcolumns 2023 in the above-mentioned covering layer is the same as described above and will not be repeated here.

[0172] The above is an example of the structure of sub-pixels for emitting R and G light in an LED chip 20 capable of achieving full-color display. In other embodiments of the present application, the sub-pixels for emitting B light in the above-mentioned LED chip 20 may not require the above-mentioned covering layer containing the color conversion material. For example, as shown in Figure 20 (a cross-sectional view obtained by cutting along the dotted line O5-O6 in Figure 3B), the LED chip 20 may include multiple light-emitting devices, such as a first light-emitting device 201a, a second light-emitting device 201b, and a third light-emitting device 201c, and multiple covering layers, such as a first covering layer 202a and a second covering layer 202b. In addition, the above-mentioned LED chip 20 may also include a transparent structure 400.

[0173] On this basis, the first covering layer 202a covers the light-emitting layer 2011 of the first light-emitting device 201a, the second covering layer 202b covers the light-emitting layer 2011 of the second light-emitting device 201b, and the transparent structure 400 covers the light-emitting layer 2011 of the third light-emitting device 201c. The initial light emitted by the first light-emitting device 201a, the second light-emitting device 201b, and the third light-emitting device 201c can be B light. Similarly, the first covering layer 202a and the second covering layer 202b can perform color conversion on the initial light emitted by the first light-emitting device 201a and the second light-emitting device 201b, respectively, with the converted light being R light and G light, respectively. Furthermore, the transparent structure 400 can directly transmit the initial light emitted by the third light-emitting device 201c, i.e., B light. Therefore, the light from the first covering layer 202a, the second covering layer 202b and the transparent structure 400 are the three primary colors respectively, and the areas where the first light-emitting device 201a, the second light-emitting device 201b and the third light-emitting device 201c are located can be used as R sub-pixels, G sub-pixels and B sub-pixels respectively, thereby enabling the LED chip 20 to achieve full-color display.

[0174] For example, the transparent structure 400 may be a transparent resin layer, or alternatively, a cavity structure containing air. The present application does not limit the specific structure and material of the transparent structure 400, as long as the transparent structure 400 completely or nearly completely transmits the initial light emitted by the third light-emitting device 201c. The light transmittance of the transparent structure 400 may be greater than or equal to 80%.

[0175] The above is an example of the structure and manufacturing method of the LED chip 20, taking the case where the above-mentioned LED chip 20 is a micro (or mini) LED chip and the light-emitting device 201 in the LED chip 20 is a micro (or mini) LED light-emitting device. In other embodiments of the present application, when the above-mentioned LED chip 20 is an OLED chip, the light-emitting device 201 in the LED chip 20 can adopt an OLED light-emitting device as shown in Figure 5B. Based on this, the covering layer 202 shown in Figure 6 can be arranged on the side of the second electrode 212 of the OLED light-emitting device in Figure 5B away from the light-emitting layer 2011. The periodic and orderly arrangement of the multiple nano-micropillars 2023 in the covering layer 202 and the manufacturing method of the covering layer 202 are the same as described above and will not be repeated here.

[0176] The above description uses the example of the cover layer 202 shown in FIG6 being fabricated on the light-emitting side (e.g., the side facing away from the driver backplane 200) of the light-emitting device 201 to illustrate the structure and fabrication method of the LED chip 20. In other embodiments of the present application, when the LED chip 20 is a micro (or mini) LED chip and the light-emitting device 201 in the LED chip 20 is a micro (or mini) LED light-emitting device, the cover layer 202 may also be fabricated within the light-emitting device 201.

[0177] Specifically, as shown in FIG21 , the light-emitting device 201 may include a first semiconductor layer 2012, which is stacked on a side of the light-emitting layer 2011 facing away from the cover layer 202. The first semiconductor layer 2012 may include the aforementioned first semiconductor material. For example, the material used for the nanopillars 2023 of the cover layer 202 may include a color-conversion material, and the substrate layer 2021 may include a second semiconductor material. The first and second semiconductor materials have different doping types. The arrangement of the first and second semiconductor materials and the color-conversion material is the same as described above and will not be further described here.

[0178] Based on this, when the material used for nano-pillars 2023 includes a color conversion material, the nano-pillars 2023 can be disposed within a substrate layer 2021 primarily composed of the aforementioned second semiconductor material. Because the substrate layer 2021 composed of the second semiconductor material can be disposed on the light-emitting side (facing away from the driver backplane 200) of the light-emitting layer 2011, the distance between the nano-pillars 2023 and the light-emitting layer 2011 along the Z direction can be reduced. This reduces the distance between the initial light emitted by the light-emitting layer 2011, such as B light, and the color conversion material (e.g., nano-pillars 2023), reducing the probability of light loss during the initial light's entry into the color conversion material, thereby improving the color conversion efficiency.

[0179] Alternatively, as another example, the material used for the substrate layer 2021 shown in FIG21 can include a color conversion material, and the nanopillars 2023 can include a second semiconductor material. Similarly, the nanopillars 2023 and the substrate layer 2021 can be disposed on the light-emitting side (away from the driving backplane 200) of the light-emitting layer 2011 to reduce the distance between the initial light emitted by the light-emitting layer 2011 and the color conversion material (e.g., the nanopillars 2023).

[0180] Based on this, as shown in Figure 21, the light-emitting device 201 also includes a first electrode 211 and a second electrode 212 electrically connected to the driving backplane 200. The configuration of the first electrode 211 is the same as described above and will not be repeated here. The second electrode 221 and a portion of the second electrode 212 are located between the substrate layer 2021 and the nano-micropillars 2023. Similarly, when the above-mentioned LED chip 20 includes multiple light-emitting devices, in order to separately control the luminous brightness of different light-emitting devices, the first electrodes 211 of the different light-emitting devices can be connected into an integrated structure, and the second electrodes 212 of the different light-emitting devices can be insulated.

[0181] The following describes an example method for fabricating the LED chip 20 shown in FIG21 . For example, as shown in FIG22( a ), a second semiconductor layer 2013 can be formed on a surface of the light-emitting layer 2011 of the light-emitting device 201 that faces away from the driver backplane 200. The second semiconductor layer 2013 can include the aforementioned second semiconductor material. Next, a photoresist 61 is formed on a surface of the second semiconductor layer 2013 that faces away from the light-emitting layer 2011.

[0182] Then, as shown in FIG22(b), the photoresist may be patterned using a photolithography process to form a mask 51. Next, as shown in FIG22(c), an etching process or an electrochemical process may be used to remove the portion of the second semiconductor layer 2013 not covered by the mask 51, thereby etching a plurality of periodically and orderly arranged nanopores 501 or a periodically and orderly arranged nanopillars 2023 as shown in FIG21 on the second semiconductor layer 2013.

[0183] Next, as shown in FIG23(a), a second electrode 212 is formed within the nanopore 501, covering the sidewalls and bottom of the nanopore 501. Alternatively, a second electrode 212 is formed between the plurality of nanopillars 2023, covering the sidewalls of the nanopillars 2023 and the upper surface of the light-emitting layer 2011. The second electrode 212 can be made of the aforementioned transparent conductive material, thereby transmitting light emitted by the light-emitting device 201, allowing the light to enter the nanopillars 2023 containing the color conversion material or the substrate layer 2021.

[0184] Next, as shown in FIG23( b ), a color conversion material is filled in the nanopore 501 where the second electrode 212 is formed by electrophoresis or spin coating to form a plurality of nanocolumns 2023 . In this case, the material of the nanocolumns 2023 includes the color conversion material.

[0185] Alternatively, when the second semiconductor layer 2013 is patterned using the mask 51 shown in FIG23(b) to form periodically and orderly arranged nano-pillars 2023 as shown in FIG23(b), the color conversion material can be filled between the plurality of nano-pillars 2023 by spin coating or electrophoresis to form the base layer 2021 shown in FIG23(b), thereby forming the covering layer 202 covering the light-emitting layer 2011. Therefore, the material of the base layer 2021 includes the color conversion material.

[0186] On this basis, as shown in (b) of FIG23 , the manufacturing method further includes forming an encapsulation layer 60 on the side of the covering layer 202 away from the driving backplane 200 . The setting method of the encapsulation layer 60 is the same as described above and will not be repeated here.

[0187] The above is only a specific embodiment of the present application, but the scope of protection of this application is not limited to this. Any changes or substitutions within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A light emitting diode chip, characterized in that: include: A light emitting device, the light emitting device comprising a light emitting layer; A covering layer, covering the light-emitting layer; the covering layer comprises: A substrate layer, wherein a vertical projection of the light-emitting layer on the substrate layer is located within the range of the substrate layer; A nano-micro-column array structure is disposed in the substrate layer, the nano-micro-column array structure comprises a plurality of nano-micro-columns, one end of the nano-micro-columns away from the light-emitting layer penetrates the substrate layer, and the extension direction of the nano-micro-columns is perpendicular to the light-emitting layer; The material used for the nano-microcolumns includes a color conversion material, and the refractive index of the color conversion material is greater than the refractive index of the material used for the substrate layer; or the material used for the substrate layer includes a color conversion material, and the refractive index of the color conversion material is greater than the refractive index of the material used for the nano-microcolumns.

2. The light emitting diode chip according to claim 1, characterized in that: The nano-micro-column array structure has at least two periodic patterns; the vertical projection of the line connecting the geometric centers of at least two of the nano-micro-columns on the light-emitting layer constitutes the periodic pattern.

3. The light emitting diode chip according to claim 2, characterized in that: The at least two periodic patterns have the same shape.

4. The light emitting diode chip according to claim 2 or 3, characterized in that: The spacing between two adjacent nano-micro-pillars forming the same periodic pattern is the same.

5. The light emitting diode chip according to any one of claims 2 to 4, characterized in that: The at least two periodic patterns are nested in sequence.

6. The light emitting diode chip according to claim 5, characterized in that: The geometric centers of the at least two periodic patterns of the nano-micro-pillar array structure overlap.

7. The light emitting diode chip according to any one of claims 2 to 4, characterized in that: The at least two periodic patterns are arranged in an array.

8. The light emitting diode chip according to claim 7, characterized in that: At least two of the nano-micro-pillars constituting the same periodic pattern have different vertical projection areas on the light-emitting layer.

9. The light emitting diode chip according to any one of claims 2 to 8, characterized in that: The periodic pattern is a circle, a triangle, a rectangle or a regular polygon.

10. The light emitting diode chip according to any one of claims 1 to 9, characterized in that: The vertical projection of the nano-microcolumn on the light-emitting layer is at least one of a circle and a polygon.

11. The light emitting diode chip according to any one of claims 1 to 10, characterized in that: The color conversion material is an optically anisotropic material, and the color conversion material is arranged in an orientation along a first direction, and the first direction is perpendicular to the light-emitting layer.

12. The light emitting diode chip according to claim 11, characterized in that: The color conversion material includes a quantum dot material, and the shape of the quantum dot material is at least one of a nano column, a nano sheet or a nano sphere.

13. The light emitting diode chip according to any one of claims 1 to 12, characterized in that: The light emitting device further comprises: A first semiconductor layer; stacked with the light-emitting layer, the first semiconductor layer comprising a first semiconductor material; A second semiconductor layer is stacked and arranged on a side of the light-emitting layer away from the first semiconductor layer, the second semiconductor layer comprises a second semiconductor material; the first semiconductor material and the second semiconductor material have different doping types; Wherein, the covering layer is arranged on a side of the second semiconductor layer away from the light-emitting layer.

14. The light emitting diode chip according to claim 13, characterized in that: The light emitting device further comprises: A driving back plate, disposed on a side of the first semiconductor layer away from the light-emitting layer; A first electrode is disposed between the first semiconductor layer and the driving backplane, and the first electrode is electrically connected to the driving backplane; The second electrode is arranged on a side of the second semiconductor layer away from the light emitting layer, and the second electrode is electrically connected to the driving backplane.

15. The light emitting diode chip according to any one of claims 1 to 12, characterized in that: The light emitting device further comprises a first semiconductor layer, which is stacked and arranged on the light emitting layer away from the covering On one side of the layer, the first semiconductor layer includes a first semiconductor material; In the case where the material used for the nano-microcolumns includes the color conversion material, the material used for the substrate layer includes a second semiconductor material; or, In the case where the material used for the substrate layer includes a color conversion material, the material used for the nano-microcolumns includes a second semiconductor material; The first semiconductor material and the second semiconductor material have different doping types.

16. The light emitting diode chip according to claim 15, characterized in that: The light emitting device further comprises: A driving back plate, disposed on a side of the first semiconductor layer away from the light-emitting layer; A first electrode is disposed between the first semiconductor layer and the driving backplane, and the first electrode is electrically connected to the driving backplane; A second electrode, a portion of which is located between the substrate layer and the nano-micro-pillar; the second electrode is electrically connected to the driving backplane, and the second electrode comprises a transparent conductive material.

17. The light emitting diode chip according to claim 14 or 16, characterized in that: The light emitting diode chip comprises at least two light emitting devices, the first electrodes of adjacent light emitting devices are connected to form an integral structure, and the second electrodes of adjacent light emitting devices are insulated.

18. The light emitting diode chip according to any one of claims 13 to 17, characterized in that: The light-emitting layer is a semiconductor active layer; The first semiconductor material is an N-type doped semiconductor material, and the second semiconductor material is a P-type doped semiconductor material; or, the first semiconductor material is a P-type doped semiconductor material, and the second semiconductor material is an N-type doped semiconductor material.

19. The light emitting diode chip according to any one of claims 1 to 12, characterized in that: The light-emitting layer is an organic light-emitting layer.

20. The light emitting diode chip according to any one of claims 1 to 19, characterized in that: In the case where the material used for the nano-microcolumns includes a color conversion material, the material used for the substrate layer includes at least one of silicon monoxide, silicon dioxide and aluminum oxide; or, In the case that the material used for the substrate layer includes a color conversion material, the material used for the nano-microcolumns includes at least one of silicon monoxide, silicon dioxide and aluminum oxide.

21. The light emitting diode chip according to any one of claims 1 to 20, characterized in that: When the material used for the nano-micro-column includes the color conversion material, the height of the nano-micro-column is 0.1 μm to 10 μm; or, When the material used for the base layer includes a color conversion material, the thickness of the base layer is 0.1 μm to 10 μm.

22. The light emitting diode chip according to any one of claims 1 to 21, characterized in that: The light emitting diode chip comprises a first light emitting device, a second light emitting device, a first covering layer and a second covering layer, wherein the first covering layer covers the light emitting layer of the first light emitting device, and the second covering layer covers the light emitting layer of the second light emitting device; The light emitting diode chip further comprises: A planar layer, disposed between the first light emitting device and the second light emitting device, and the planar layer is connected to the first light emitting device and the second light emitting device; a retaining wall, arranged in the flat layer, and the retaining wall is located between the first light emitting device and the second light emitting device; a portion of the flat layer is spaced between the retaining wall and the first light emitting device, and between the retaining wall and the second light emitting device; Wherein, the base material layer of the first covering layer and the base material layer of the second covering layer are connected to form an integrated structure and cover the retaining wall.

23. The light emitting diode chip according to any one of claims 1 to 21, characterized in that: The light emitting diode chip comprises a first light emitting device, a second light emitting device, a first covering layer and a second covering layer, wherein the first covering layer covers the light emitting layer of the first light emitting device, and the second covering layer covers the light emitting layer of the second light emitting device; The light emitting diode chip further comprises: A retaining wall, disposed between the first light emitting device and the second light emitting device and between the first covering layer and the second covering layer; The retaining wall is connected to the first light emitting device, the second light emitting device, the substrate layer of the first covering layer, and the substrate layer of the second covering layer.

24. The light emitting diode chip according to any one of claims 1 to 23, characterized in that: The light emitting diode chip comprises a first light emitting device, a second light emitting device and a third light emitting device, and the initial light emitted by the first light emitting device, the second light emitting device and the third light emitting device are the same; The light-emitting diode chip comprises a first covering layer and a second covering layer; the light-emitting diode chip further comprises a transparent structure; the first covering layer covers the light-emitting layer of the first light-emitting device, the second covering layer covers the light-emitting layer of the second light-emitting device, and the transparent structure covers the light-emitting layers of the third light-emitting device respectively; The light from the first covering layer, the light from the second covering layer, and the initial light are three primary color lights respectively.

25. A display screen, characterized in that: The display screen has a plurality of pixel areas; The display screen comprises a plurality of light-emitting diode chips as claimed in any one of claims 1 to 24, wherein the light-emitting diode chip comprises a light-emitting device; the plurality of light-emitting diode chips are arranged in an array, and at least three adjacent light-emitting diode chips that respectively emit three primary colors of light are located in the same pixel area; or, The display screen comprises a light-emitting diode chip as described in any one of claims 1 to 24, wherein the light-emitting diode chip comprises a plurality of light-emitting devices arranged in an array, and at least three adjacent light-emitting devices that respectively emit three primary colors of light are located in the same pixel area.

26. An electronic device, characterized in that: include: processor; as well as, The display screen as claimed in claim 25, wherein the display screen is electrically connected to the processor, and the processor is used to control the display screen to display an image.

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