A flip-chip LED chip, a flip-chip LED chip manufacturing method and a display device

Abstract

The present application discloses a flip-chip LED chip, a method for manufacturing a flip-chip LED chip and a display device, and relates to the technical field of display elements and display equipment. In the technical solution provided in the present application, light-transmitting protrusions arranged in an array on a light-emitting surface of a substrate are divided into a first arrangement area and a second arrangement area, wherein the coverage rate of the light-transmitting protrusions on the light-emitting surface in the first arrangement area is greater than the coverage rate of the light-transmitting protrusions on the light-emitting surface in the second arrangement area. Meanwhile, the first arrangement area is located in the central part of the light-emitting surface, and the light-transmitting protrusions arranged in the central part of the light-emitting surface are denser than those arranged in the edge part of the light-emitting surface. A large part of the light emitted from the central part of the light-emitting surface with stronger light in the positive direction of the light-emitting surface will be reflected or transmitted to change the light emission path. Compared with the related technical solutions, the light intensity on the side of the chip is more ideal.

Description

Technical Field

[0001] The present application relates to the technical field of display elements and display devices, and in particular to a flip-chip LED chip, a flip-chip LED chip manufacturing method and a display device. Background Art

[0002] LED chips have the advantages of high brightness, long life, small size and low power consumption, and have been widely used in display device technology fields such as display panels. In the field of light emitting diode technology, different requirements are put forward for the light shape and light angle of the light emitting diode in different situations. For example, the light emitting diode is required to have a larger light angle.

[0003] The Chinese invention patent publication with publication number CN109244222A discloses an LED chip with a larger light output angle, which mainly uses light-transmitting protrusions to partially reflect light or change the transmission of the light output path, thereby allowing more light to be emitted from the side of the flip-chip LED chip, thereby expanding the light output angle of the LED chip. However, for the above technical solution, the positive direction light output at the central part of the substrate light output surface is greater than the positive direction light output at its edge, but the light-transmitting protrusions are evenly distributed on the light output surface, so a large part of the light will still be emitted in the positive direction through the central part of the light output surface, the distribution of the light-transmitting protrusions is unreasonable, and the light intensity of the light output from the side of the chip is weak. Summary of the invention

[0004] In summary, the technical problem to be solved by the present application is to provide a flip-chip LED chip, whose light-transmitting protrusions are reasonably distributed and the light intensity of the side light is more ideal.

[0005] In order to solve the above technical problems, the technical solution adopted in this embodiment is:

[0006] In a first aspect, the present application provides a flip-chip LED chip, comprising:

[0007] A substrate having a light emitting surface and a light facing surface disposed opposite to each other;

[0008] A light emitting structure, which is disposed on the light-facing surface and is used to emit light of a preset wavelength;

[0009] A lower reflection layer, the lower reflection layer being arranged on a surface of the light emitting structure facing away from the substrate;

[0010] The light-transmitting protrusions are in a shape protruding in a direction away from the substrate and are arranged in an array on the light-emitting surface at intervals from each other, the array formed by each of the light-transmitting protrusions includes at least a first arrangement area and a second arrangement area, the first arrangement area is arranged in the central part of the light-emitting surface, the second arrangement area is arranged on the outside of the first arrangement area, and the coverage rate of the light-transmitting protrusions on the light-emitting surface in the first arrangement area is greater than the coverage rate of the light-transmitting protrusions on the light-emitting surface in the second arrangement area.

[0011] Optionally, in some embodiments of the present application, the second arrangement area surrounds the first arrangement area and is arranged at an edge of the light emitting surface.

[0012] Optionally, in some embodiments of the present application, the cross-section of the light-transmitting protrusion perpendicular to the light-emitting surface is in any one of an arcuate shape, a trapezoidal shape, and a triangle, or a combination of any two of them.

[0013] Optionally, in some embodiments of the present application, the size and shape of each of the light-transmitting protrusions are consistent, and in the first arrangement area, there is a first spacing between any two adjacent light-transmitting protrusions, and in the second arrangement area, there is a second spacing between any two adjacent light-transmitting protrusions, wherein the first spacing is smaller than the second spacing.

[0014] Optionally, in some embodiments of the present application, each of the light-transmitting protrusions includes a semi-transmissive and semi-reflective metal layer and an upper reflective layer, and the semi-transmissive and semi-reflective metal layer and the upper reflective layer are stacked in sequence along a direction away from the light-emitting surface, wherein the lower reflective layer reflects part of the light reflected by the light-transmitting protrusion back to the light-transmitting protrusion, thereby causing the light to be emitted after resonance enhancement.

[0015] Optionally, in some embodiments of the present application, the upper reflection layer includes at least one refractive layer, there is a refractive layer connected to the semi-transmissive and semi-reflective metal layer, and its refractive index is configured to be higher than that of the semi-transmissive and semi-reflective metal layer.

[0016] Optionally, in some embodiments of the present application, the upper reflective layer includes a plurality of refractive layers stacked in sequence, the refractive indices of two adjacent refractive layers are different, and each of the refractive layers is alternately arranged in the form of a high refractive index refractive layer and a low refractive index refractive layer along a direction away from the light emitting surface.

[0017] Optionally, in some embodiments of the present application, the light-emitting structure includes a first semiconductor layer, an active layer, and a second semiconductor layer in sequence, the conductivity types of the first semiconductor layer and the second semiconductor layer are opposite to each other, the first semiconductor layer, the active layer, and the second semiconductor layer are stacked in sequence on the light-facing surface, and the light-emitting structure also includes a first electrode and a second electrode, the first electrode is connected to the first semiconductor layer, and the second electrode is connected to the second semiconductor layer.

[0018] Optionally, in some embodiments of the present application, a first through hole and a second through hole are provided on the lower reflection layer, the first electrode extends out of the lower reflection layer through the first through hole, and the second electrode extends out of the lower reflection layer through the second through hole.

[0019] In a second aspect, the present application provides a display device, comprising the flip-chip LED chip as described in the first aspect.

[0020] In a third aspect, the present application provides a method for manufacturing a flip-chip LED chip, comprising:

[0021] Providing a substrate, the substrate having a light emitting surface and a light facing surface disposed opposite to each other;

[0022] Depositing a first semiconductor layer, an active layer, and a second semiconductor layer in sequence on the light-facing surface of the substrate;

[0023] Depositing a semi-transmissive and semi-reflective metal layer and an upper reflective layer in sequence on the light-emitting surface of the substrate;

[0024] Etching the semi-transmissive and semi-reflective metal layer and the upper reflective layer at the central portion of the light emitting surface to form light-transmitting protrusions that are located in the first arrangement area and arranged in an array at intervals;

[0025] Etching the portions of the semi-transmissive and semi-reflective metal layer and the upper reflective layer corresponding to the outer side of the central portion of the light emitting surface to form light-transmitting protrusions that are located in the second arrangement area and arranged in an array at intervals, wherein the coverage rate of the light-transmitting protrusions on the light emitting surface in the first arrangement area is greater than the coverage rate of the light-transmitting protrusions on the light emitting surface in the second arrangement area;

[0026] In summary, due to the adoption of the above technical solution, the present application at least includes the following beneficial effects:

[0027] The flip-chip LED chip provided in the present application mainly optimizes and improves the arrangement of the light-transmitting protrusions. In the technical solution provided in the present application, the light-transmitting protrusions arrayed on the light-emitting surface of the substrate are divided into a first arrangement area and a second arrangement area, wherein the coverage rate of the light-transmitting protrusions on the light-emitting surface in the first arrangement area is greater than the coverage rate of the light-transmitting protrusions on the light-emitting surface in the second arrangement area. At the same time, the first arrangement area is located in the central part of the light-emitting surface. The light-transmitting protrusions arranged in the central part of the light-emitting surface are denser than the light-transmitting protrusions arranged in the edge part of the light-emitting surface. A large part of the light emitted from the central part of the light-emitting surface with stronger light in the positive direction will be reflected or transmitted to change the light emission path. Compared with the related technical solutions, the distribution of the light-transmitting protrusions is more reasonable, adapted to the light emission conditions of the chip, and the light intensity on the side of the chip is more ideal. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings of the embodiments are briefly introduced below. Obviously, the drawings described below only relate to some embodiments of the present application, but are not intended to limit the present application, wherein:

[0029] Figure 1 This is a cross-sectional schematic diagram of the flip-chip LED chip in Example 1 provided by the present invention;

[0030] Figure 2 Schematic diagram of the division of the first arrangement area and the second arrangement area on the light-emitting surface of the substrate in Example 1 provided by the present invention;

[0031] Figure 3 A cross-sectional schematic diagram of a flip-chip LED chip in another embodiment of the present invention;

[0032] Figure 4 This is a schematic cross-sectional view of a light-transmitting protrusion in a flip-chip LED chip in Example 1 provided by the present invention;

[0033] Figure 5 The figure is a schematic diagram of the process of the preparation method in Example 1 provided by the present invention. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of them. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0035] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a unique orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0036] In the application, the word "exemplary" is used to mean "serving as an example, illustration, or description". Any embodiment described in the present application as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. The following description is given to enable any technician in the field to implement and use the present application. In the following description, details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art can recognize that the present application can be implemented without using these specific details. In other instances, known structures and processes are not described in detail to avoid obscuring the description of the present application with unnecessary details. Therefore, the present application is not intended to be limited to the embodiments shown, but is consistent with the widest scope consistent with the principles disclosed in the present application.

[0037] Example 1

[0038] See also Figure 1 The main body of this embodiment is a flip-chip LED chip, which includes:

[0039] A substrate 10, the substrate 10 having a light emitting surface 11 and a light facing surface arranged opposite to each other;

[0040] A light emitting structure 30, which is disposed on the light-facing surface and is used to emit light of a preset wavelength;

[0041] A low reflection layer 40, which is disposed on a surface of the light emitting structure 30 that faces away from the substrate 10;

[0042] The light-transmitting protrusions 20 are in a shape protruding in a direction away from the substrate 10 and are arranged in an array on the light-emitting surface 11 at intervals from each other. The array formed by each light-transmitting protrusion 20 includes at least a first arrangement area 20a and a second arrangement area 20b. The first arrangement area 20a is arranged in the central part of the light-emitting surface 11, and the second arrangement area 20b is arranged on the outside of the first arrangement area 20a. The coverage rate of the light-transmitting protrusions 20 on the light-emitting surface 11 in the first arrangement area 20a is greater than the coverage rate of the light-transmitting protrusions 20 on the light-emitting surface 11 in the second arrangement area 20b.

[0043] For the LED chip, the positive light emitted from the center of the light emitting surface 11 is greater than the positive light emitted from the edge of the light emitting surface 11. Figure 2 For the convenience of display, Figure 2 Only the areas of the light emitting surface 11 corresponding to the first arrangement area 20a and the second arrangement area 20b are shown. The present application divides the light-transmitting protrusions 20 arranged in an array on the light emitting surface 11 of the substrate 10 into the first arrangement area 20a and the second arrangement area 20b, wherein the coverage of the light-transmitting protrusions 20 on the light emitting surface 11 in the first arrangement area 20a is greater than the coverage of the light-transmitting protrusions 20 on the light emitting surface 11 in the second arrangement area 20b. At the same time, the first arrangement area 20a is located in the central part of the light emitting surface 11. The light-transmitting protrusions 20 arranged in the central part of the light emitting surface 11 are denser than the light-transmitting protrusions 20 arranged at the edge of the light emitting surface 11, which is adapted to the light emitting conditions of the chip. Most of the positive direction light originally emitted from the central part of the light emitting surface 11 will be reflected or transmitted to change the light emitting path, and emitted along the side, thereby improving the light intensity of the light emitted from the side of the chip.

[0044] It is understandable that in the prior art described above, since the light-transmitting protrusions 20 are evenly arranged, there are many lights emitted in the positive direction from the central part of the light-emitting surface 11, while the lights emitted from the edge of the light-emitting surface 11 are weak in the positive direction, and the light-transmitting protrusions 20 with a higher coverage rate cannot significantly increase the light intensity at the side. Compared with the prior art described above, this embodiment rationalizes the arrangement density of the light-transmitting protrusions 20 at different positions, thereby changing the light path of some of the light that would originally be emitted in the positive direction from the central part of the light-emitting surface 11 and emitting from the side, thereby increasing the light intensity of the light emitted from the side of the chip.

[0045] It is also understandable that the implementers can also design the corresponding pattern on the light-emitting surface 11 according to the actual needs of the chip's light-emitting method, and regionally change the light-emitting path so that the light is directly emitted from the pattern area through the light-emitting surface 11, thereby directly customizing the change in the light shape and light-emitting angle.

[0046] It should be noted that the coverage rate described above can reflect the chip's ability to emit light in the positive direction in the area corresponding to the light-emitting surface 11. Under the premise that the size of the light-transmitting protrusions 20 is consistent, in the area with a unit area on the light-emitting surface 11, the number of light-transmitting protrusions 20 arranged is small, and a smaller area of ​​the light-emitting surface 11 is covered by the light-transmitting protrusions 20, and more light will be emitted in the positive direction from the gaps between the light-transmitting protrusions 20. At this time, the light intensity of the light in the positive direction of the light-emitting surface 11 is higher, while the light intensity of the light in the side direction is weaker. At the same time, in the area with a unit area on the light emitting surface 11, the more the number of arranged light-transmitting protrusions 20 is, the larger the area of ​​the light emitting surface 11 is covered by the light-transmitting protrusions 20, and more light will be reflected by the light-transmitting protrusions 20 or emitted with a changed light emitting path. The reflected light will be reflected and emitted from the side of the chip, or will be emitted after being reflected by the lower reflection layer 40, thereby reducing the light intensity of the light in the positive direction of the light emitting surface 11 and increasing the light intensity in the side direction.

[0047] In addition, it should be noted that, in addition to the consistent size of each light-transmitting protrusion 20 shown in this embodiment, the implementer can also adjust the coverage of the light-transmitting protrusion 20 per unit area on the light-emitting surface 11 in the first arrangement area 20a and the second arrangement area 20b by changing the size of the light-transmitting protrusion 20.

[0048] More specifically, in the present embodiment, the size and shape of each light-transmitting protrusion 20 are consistent. In the first arrangement area 20a, there is a first spacing between any two adjacent light-transmitting protrusions 20, and in the second arrangement area 20b, there is a second spacing between any two adjacent light-transmitting protrusions 20, wherein the first spacing is smaller than the second spacing. Among them, the implementer can select the specific values ​​of the above-mentioned first spacing and the second spacing according to their own needs. As long as the first spacing is smaller than the second spacing, the number of light-transmitting protrusions 20 arranged per unit area in the first arrangement area 20a and the second arrangement area 20b will be different, thereby making the coverage rate of the light-transmitting protrusions 20 on the light-emitting surface 11 in the first arrangement area 20a greater than the coverage rate of the light-transmitting protrusions 20 on the light-emitting surface 11 in the second arrangement area 20b. Schematically, the first spacing can be selected between 0.5nm and 5nm, and the second spacing can be selected between 2 and 10nm.

[0049] For the first arrangement area 20a and the second arrangement area 20b, as long as the first arrangement area 20a is arranged in the central part of the light emitting surface 11, and the second arrangement area 20b is arranged on any one side or outside any several sides of the first arrangement area 20a. For example, in another embodiment, the second arrangement area 20b is arranged outside one side of the first arrangement area 20a. For another example, in another embodiment, the second arrangement area 20b is arranged outside the opposite sides of the first arrangement area 20a. In the present embodiment, the second arrangement area 20b surrounds the first arrangement area 20a and is arranged at the edge of the light emitting surface 11.

[0050] Regarding the shape of the light-transmitting protrusion 20, in this embodiment, the light-transmitting protrusion 20 is in the shape of a frustum, and the implementer can specifically set the shape of the light-transmitting protrusion 20 according to their own needs, for example, the light-transmitting protrusion 20 is set to: the cross section perpendicular to the light-emitting surface 11 is in any one of an arcuate, a trapezoid, and a triangle, or any combination of several thereof. This application does not make any special limitation on this.

[0051] In addition, it can be understood that, for the light-transmitting protrusion 20 described above, when the light enters the light-transmitting protrusion 20 from the substrate 10, it will be partially reflected. At the same time, when the light is emitted from the outer contour of the light-transmitting protrusion 20, since the outer contour of the protrusion structure is not flat compared to the light-emitting surface 11, the path of the light will change greatly, realizing the change of the light-emitting angle, and avoiding the light-emitting direction being concentrated in one direction. Figure 3 Taking the semi-spherical light-transmitting protrusion 20 used in another embodiment as an example, when light is emitted from the spherical surface of the light-transmitting protrusion 20, the light will be emitted in all directions. At the same time, in this embodiment, in order to enhance the partial reflection effect of the light-transmitting protrusion 20, each light-transmitting protrusion 20 includes a semi-transmitting and semi-reflecting metal layer 21 and an upper reflection layer 22, and the semi-transmitting and semi-reflecting metal layer 21 and the upper reflection layer 22 are sequentially stacked in a direction away from the light-emitting surface 11.

[0052] At the same time, the technical solution provided in this embodiment is to process a light-transmitting protrusion 20 on a flip-chip LED that can resonate and enhance light of a preset wavelength. An upper reflection structure (including a semi-reflective and semi-transmissive film layer and an upper reflection layer sequentially stacked on the light-emitting surface 11 in the form of a whole surface) is originally provided on the light-emitting surface 11 of the substrate 10, which is used to cooperate with the lower reflection layer 40 to form an optical resonance structure to enhance the light of a preset wavelength. This embodiment mainly performs patterning on the upper reflection structure to form the light-transmitting protrusion 20. It can be understood that although the light-transmitting protrusion 20 reduces the coverage of the upper reflection structure, the upper reflection structure can still play a certain degree of resonance. Therefore, in this embodiment, the lower reflection layer 40 reflects part of the light reflected by the light-transmitting protrusion 20 back to the light-transmitting protrusion 20, so that the light is emitted after resonance enhancement in the optical resonance structure.

[0053] Here, the light of preset wavelength mainly refers to the light expected to be emitted by the light emitting structure 30 when power is turned on. Flip-chip LED chips generally emit light of different wavelengths depending on the light emitting structure 30. Specifically, the light of preset wavelength indicated in the foregoing may be red light, blue light, yellow light or other expected light. The resonant structure described in the foregoing is configured to match the preset wavelength, that is, the resonant structure can be roughly divided into a resonant structure for enhancing red light, a resonant structure for enhancing blue light and a resonant structure for enhancing yellow light. In detail, depending on the wavelength of light, the optical spacing between the upper reflection structure and the lower reflection layer 40 in the resonant structure is also different. Among the related technical solutions, some contents of forming an optical resonant structure using an upper reflection structure and a lower reflection layer 40 have been disclosed, so the present application will no longer summarize the contents such as the optical spacing described above.

[0054] See also Figure 4 In this embodiment, a semi-transmissive and semi-reflective metal layer 21 is mainly provided to form resonance. The semi-transmissive and semi-reflective metal layer 21 has a lower absorption rate of light and can reflect more light, thereby enhancing the resonance effect of the resonant structure. In addition, the semi-transmissive and semi-reflective metal layer 21 also has the advantage of better flatness. The semi-transmissive and semi-reflective metal layer 21 can be a single film layer of Al / Pt / Ag or a laminated structure formed by any of Al / Pt / Ag. The film thickness can be set to be thinner (for example, to ), so that the metal layer is in a semi-transmissive and semi-reflective state. Of course, the implementer can also omit the semi-transmissive and semi-reflective metal layer 21. For example, in another embodiment, each light-transmitting protrusion 20 only includes an upper reflective layer 22 stacked on the light-emitting surface 11.

[0055] More specifically, in this embodiment, the upper reflection layer 22 includes at least one refractive layer, and there is a refractive layer connected to the semi-transmissive and semi-reflective metal layer 21, and its refractive index is configured to be higher than that of the semi-transmissive and semi-reflective metal layer 21. Among them, since it is connected to the semi-transmissive and semi-reflective metal layer 21 through the refractive layer, and the refractive index of the refractive layer is higher than that of the semi-transmissive and semi-reflective metal layer 21, the outgoing light can be strongly reflected here, further enhancing the resonance effect of the resonant structure.

[0056] It can be understood that the upper reflection layer 22 may be provided with only one refractive layer or multiple refractive layers. In the present embodiment, in addition to the refractive layer connected to the semi-transmissive and semi-reflective metal layer 21 as described above, it also includes multiple refractive layers stacked in sequence, and the two adjacent refractive layers have different refractive indices, so that the upper reflection layer 22 constitutes a Bragg reflection layer to enhance the reflection effect.

[0057] In detail, each refractive layer is alternately arranged in the direction opposite to the light exiting surface 11 in the form of a high refractive index refractive layer and a low refractive index refractive layer. The high refractive index refractive layer here refers to a layer having a higher refractive index than the adjacent low refractive index refractive layer, and the corresponding low refractive index refractive layer refers to a layer having a lower refractive index than the adjacent high refractive index refractive layer. The high refractive index refractive layer can be any one of TiO, TiO2, Ti3O5, HfO2, and ZrO2, and the low refractive index refractive layer can be SiO2, SiN X Equal film layer.

[0058] Regarding the lower reflection layer 40, it is mainly used to reflect the reflected light back to the light-emitting surface 11 of the substrate 10. In the present embodiment, the lower reflection layer 40 adopts a Bragg reflection layer structure, whose reflectivity is higher than the reflectivity of the upper reflection layer 22, and is arranged between the two sides of the active layer 32 together with the semi-transmissive and semi-reflective metal layer 21 and the upper reflection layer 22, to form an optical resonance structure, thereby enhancing the emitted light and improving the color purity of the emitted light.

[0059] More specifically, with regard to the light emitting structure 30, in the present embodiment, the light emitting structure 30 includes a first semiconductor layer 31, an active layer 32, and a second semiconductor layer 33 which are sequentially stacked and connected on the light-facing surface of the substrate 10, the conductivity types of the first semiconductor layer 31 and the second semiconductor layer 33 are opposite to each other, the first semiconductor layer 31, the active layer 32, and the second semiconductor layer 33 are sequentially stacked on the substrate 10, and the light emitting structure 30 also includes a first electrode 51 and a second electrode 52, the first electrode 51 is connected to the first semiconductor layer 31, and the second electrode 52 is connected to the second semiconductor layer 33.

[0060] The first semiconductor layer 31 is an N-type semiconductor layer, and the second semiconductor layer 33 is a P-type semiconductor layer. The corresponding first electrode 51 is an N-type electrode, and the second electrode 52 is a P-type electrode. Correspondingly, the lower reflection layer 40 is provided with a first through hole and a second through hole. The first electrode 51 extends out of the lower reflection layer 40 through the first through hole, and the second electrode 52 extends out of the lower reflection layer 40 through the second through hole. The portion where the first electrode 51 and the second electrode 52 extend out of the lower reflection layer 40 constitutes a pad portion.

[0061] See also Figure 5 This embodiment also provides a method for manufacturing a flip-chip LED chip as described above, comprising the steps of:

[0062] S1. Provide a substrate 10, wherein the substrate 10 has a light emitting surface 11 and a light facing surface that are arranged opposite to each other;

[0063] S2, depositing a first semiconductor layer 31, an active layer 32 and a second semiconductor layer 33 in sequence on the light-facing surface of the substrate 10;

[0064] S3, sequentially depositing a semi-transmissive and semi-reflective metal layer 21 and an upper reflective layer 22 on the light emitting surface 11 of the substrate 10;

[0065] S4, etching the semi-transmissive and semi-reflective metal layer 21 and the upper reflective layer 22 at the central portion of the light emitting surface 11 to form light-transmissive protrusions 20 that are located in the first arrangement area 20a and arranged in an array at intervals;

[0066] S5, etching the portion of the semi-transmissive and semi-reflective metal layer 21 and the upper reflective layer 22 corresponding to the outer side of the central portion of the light emitting surface 11 to form light-transmitting protrusions 20 located in the second arrangement area 20b and arranged in an array at intervals, wherein the coverage rate of the light-transmitting protrusions 20 on the light emitting surface 11 in the first arrangement area 20a is greater than the coverage rate of the light-transmitting protrusions 20 on the light emitting surface 11 in the second arrangement area 20b;

[0067] S6. Cut and split to form core particles.

[0068] In step S4, the implementer can set a second photoresist corresponding to the second arrangement area 20b on the light-emitting surface 11 of the substrate 10, and then expose and develop the first arrangement area 20a, so as to etch and form the light-transmitting protrusions 20 arranged in the first arrangement area 20a. Then in step S5, set a first photoresist corresponding to the first arrangement area 20a on the light-emitting surface 11 of the substrate 10, and then etch the second arrangement area 20b, so as to form the light-transmitting protrusions 20 arranged in the second arrangement area 20b.

[0069] It should be noted that the first photoresist and the second photoresist described above are both positive photoresist protective films. Of course, the implementer can also use a negative photoresist protective film to realize the manufacture of the light-transmitting protrusion 20, and this application does not make any special limitation on this.

[0070] Example 2

[0071] Embodiment 2 provides a display device, including a display panel, wherein the display panel includes the flip-chip LED chip as described in Embodiment 1. It is understandable that the display device provided in this embodiment can be any display device with a flip-chip LED chip, such as a tablet, a mobile phone, a VR, a computer screen, etc., and implementers can choose accordingly according to their own needs, and this application does not specifically limit this.

[0072] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only for example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.

[0073] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0074] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more application embodiments, in the above description of the embodiments of this application, multiple features are sometimes merged into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.

[0075] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining the number of digits. Although the numerical domains and parameters used to confirm the breadth of the range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values ​​is as accurate as possible within the feasible range.

[0076] Each patent, patent application, patent application publication, and other materials, such as articles, books, specifications, publications, documents, etc., cited in this application is hereby incorporated by reference in its entirety, except for application history documents that are inconsistent with or conflicting with the content of this application, and documents that limit the broadest scope of the claims of this application (currently or later attached to this application). It should be noted that if the descriptions, definitions, and / or use of terms in the attached materials of this application are inconsistent or conflicting with the content of this application, the descriptions, definitions, and / or use of terms in this application shall prevail.

Claims

1. A flip-chip LED chip, characterized in that: include: A substrate having a light emitting surface and a light facing surface disposed opposite to each other; A light emitting structure, which is disposed on the light-facing surface and is used to emit light of a preset wavelength; A lower reflection layer, the lower reflection layer being arranged on a surface of the light emitting structure facing away from the substrate; light-transmitting protrusions, the light-transmitting protrusions are in a shape protruding in a direction away from the substrate and are arranged in an array on the light-emitting surface at intervals, the array formed by each of the light-transmitting protrusions comprises at least a first arrangement area and a second arrangement area, the first arrangement area is arranged in the central part of the light-emitting surface, the second arrangement area is arranged outside the first arrangement area, and the coverage rate of the light-transmitting protrusions on the light-emitting surface in the first arrangement area is greater than the coverage rate of the light-transmitting protrusions on the light-emitting surface in the second arrangement area; Each of the light-transmitting protrusions comprises a semi-transmitting and semi-reflecting metal layer and an upper reflecting layer, wherein the semi-transmitting and semi-reflecting metal layer and the upper reflecting layer are sequentially stacked in a direction away from the light-emitting surface, wherein the lower reflecting layer reflects part of the light reflected by the light-transmitting protrusion back to the light-transmitting protrusion, thereby causing the light to be resonantly enhanced and then emitted; The upper reflection layer includes at least one refractive layer, wherein there is one refractive layer connected to the semi-transmissive and semi-reflective metal layer, and its refractive index is configured to be higher than that of the semi-transmissive and semi-reflective metal layer; The second arrangement area surrounds the first arrangement area and is arranged at an edge of the light emitting surface.

2. The flip-chip LED chip according to claim 1, characterized in that: The cross section of the light-transmitting protrusion perpendicular to the light-emitting surface is in any one of an arcuate shape, a trapezoidal shape, and a triangle shape, or a combination of any of the above.

3. The flip-chip LED chip according to claim 1, characterized in that: The size and shape of each of the light-transmitting protrusions are consistent. In the first arrangement area, there is a first spacing between any two adjacent light-transmitting protrusions. In the second arrangement area, there is a second spacing between any two adjacent light-transmitting protrusions, wherein the first spacing is smaller than the second spacing.

4. The flip-chip LED chip according to claim 1, characterized in that: The upper reflection layer includes a plurality of refractive layers stacked in sequence, two adjacent refractive layers have different refractive indices, and each refractive layer is alternately arranged in the form of a high refractive index refractive layer and a low refractive index refractive layer along a direction opposite to the light emitting surface.

5. The flip-chip LED chip according to claim 1, characterized in that: The light-emitting structure includes a first semiconductor layer, an active layer, and a second semiconductor layer in sequence. The conductivity types of the first semiconductor layer and the second semiconductor layer are opposite to each other. The first semiconductor layer, the active layer, and the second semiconductor layer are stacked in sequence on the light-facing surface. The light-emitting structure also includes a first electrode and a second electrode. The first electrode is connected to the first semiconductor layer, and the second electrode is connected to the second semiconductor layer.

6. The flip-chip LED chip as claimed in claim 5, characterized in that: The lower reflection layer is provided with a first through hole and a second through hole, the first electrode extends out of the lower reflection layer through the first through hole, and the second electrode extends out of the lower reflection layer through the second through hole.

7. A display device, characterized in that: The invention comprises a flip-chip LED chip as claimed in any one of claims 1 to 6.

8. A method for manufacturing a flip-chip LED chip, characterized in that: include: Providing a substrate, the substrate having a light emitting surface and a light facing surface disposed opposite to each other; Depositing a first semiconductor layer, an active layer, and a second semiconductor layer in sequence on the light-facing surface of the substrate; Depositing a semi-transmissive and semi-reflective metal layer and an upper reflective layer in sequence on the light-emitting surface of the substrate; Etching the semi-transmissive and semi-reflective metal layer and the upper reflective layer at the central portion of the light emitting surface to form light-transmitting protrusions that are located in the first arrangement area and arranged in an array at intervals; The semi-transmissive and semi-reflective metal layer and the upper reflective layer are etched at portions outside the central portion of the light emitting surface corresponding to the light emitting surface to form light-transmitting protrusions that are located in the second arrangement area and arranged in an array at intervals, and the coverage rate of the light-transmitting protrusions on the light emitting surface in the first arrangement area is greater than the coverage rate of the light-transmitting protrusions on the light emitting surface in the second arrangement area.

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