Display panel

Abstract

The invention provides a display panel. The display panel comprises a substrate, a plurality of light-emitting units and a transparent medium layer, the light-emitting units are arranged on the substrate in an array mode, each light-emitting unit at least comprises a first light-emitting unit of a first light-emitting color, a second light-emitting unit of a second light-emitting color and a third light-emitting unit of a third light-emitting unit, and the first light-emitting unit, the second light-emitting unit and the third light-emitting unit are sequentially stacked on the substrate. Projections of the first light-emitting unit, the second light-emitting unit and the third light-emitting unit on the substrate are not overlapped; the transparent medium layer comprises a first transparent medium layer, a second transparent medium layer and a third transparent medium layer, the first transparent medium layer is located between the first light-emitting unit and the second light-emitting unit, the second transparent medium layer is located between the second light-emitting unit and the third light-emitting unit, and the third transparent medium layer covers the third light-emitting unit.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a display panel. Background Art

[0002] The light-emitting diode (LED)-based display panel is a new type of display technology that uses micron-level LEDs as pixels and can be applied to devices such as augmented reality (AR).

[0003] In the related art, display panels based on light emitting diodes are usually monochrome displays, and achieving full-color display is a difficult problem that needs to be solved urgently. Summary of the invention

[0004] The embodiment of the present disclosure provides a display panel, which can realize full-color display panel based on light-emitting diodes. The technical solution is as follows:

[0005] In one aspect, a display panel is provided, the display panel comprising: a substrate, a plurality of light-emitting units and a transparent medium layer;

[0006] The plurality of light-emitting unit arrays are arranged on the substrate, each of the light-emitting units at least includes a first light-emitting unit of a first light-emitting color, a second light-emitting unit of a second light-emitting color, and a third light-emitting unit of a third light-emitting color, the first light-emitting unit, the second light-emitting unit, and the third light-emitting unit are sequentially stacked on the substrate, and projections of the first light-emitting unit, the second light-emitting unit, and the third light-emitting unit on the substrate do not overlap;

[0007] The transparent medium layer comprises a first transparent medium layer, a second transparent medium layer and a third transparent medium layer, wherein the first transparent medium layer is located between the first light emitting unit and the second light emitting unit, the second transparent medium layer is located between the second light emitting unit and the third light emitting unit, and the third transparent medium layer covers the third light emitting unit;

[0008] The first electrode of the first light-emitting unit, the first electrode of the second light-emitting unit and the first electrode of the third light-emitting unit are electrically connected to the substrate respectively, and the second electrode of the first light-emitting unit, the second electrode of the second light-emitting unit and the second electrode of the third light-emitting unit are connected.

[0009] Optionally, the display panel further includes: a top electrode layer, which is arranged on the surface of the third transparent medium layer, and the second electrode of the first light-emitting unit, the second electrode of the second light-emitting unit and the second electrode of the third light-emitting unit are electrically connected to the top electrode layer.

[0010] Optionally, the second electrode of the first light-emitting unit, the second electrode of the second light-emitting unit, and the second electrode of the third light-emitting unit are electrically connected to the substrate.

[0011] Optionally, the first light emitting unit is a red light emitting unit, the second light emitting unit is a green light emitting unit, and the third light emitting unit is a blue light emitting unit.

[0012] Optionally, a projection area of ​​the first light emitting unit on the substrate is larger than a projection area of ​​the second light emitting unit on the substrate, and a projection area of ​​the first light emitting unit on the substrate is larger than a projection area of ​​the third light emitting unit on the substrate.

[0013] Optionally, the first electrode of the first light-emitting unit is directly electrically connected to the substrate, the first electrode of the second light-emitting unit is electrically connected to the substrate through the first transparent medium layer via a first conductive column, and the first electrode of the third light-emitting unit is electrically connected to the substrate through the first transparent medium layer and the second transparent medium layer via a second conductive column.

[0014] Optionally, the second electrode of the first light-emitting unit is electrically connected to the second electrode of the second light-emitting unit through the first transparent medium layer via a third conductive column, the second electrode of the second light-emitting unit is electrically connected to the second electrode of the third light-emitting unit through the second transparent medium layer via a fourth conductive column, and the second electrode of the third light-emitting unit extends from the third transparent medium layer via a fifth conductive column.

[0015] Optionally, the first light-emitting unit, the second light-emitting unit and the third light-emitting unit each include: a bonding metal layer and an epitaxial layer stacked in sequence, an insulating layer covering the bonding metal layer and the epitaxial layer, and an electrode connected to the epitaxial layer through the insulating layer.

[0016] Optionally, the second electrode of the first light-emitting unit, the second electrode of the second light-emitting unit, and the second electrode of the third light-emitting unit are in the shape of elongated strips.

[0017] Optionally, the second electrode of the first light-emitting unit, the second electrode of the second light-emitting unit, and the second electrode of the third light-emitting unit are connected to the center of the light-emitting unit.

[0018] The technical solution provided by the embodiments of the present disclosure brings the following beneficial effects:

[0019] In the embodiment of the present disclosure, each of the multiple light-emitting units on the substrate includes at least three light-emitting units with different light-emitting colors, and color display can be achieved through the three light-emitting units; at the same time, the three light-emitting units are not arranged in the same layer, but are arranged in a stacked manner and separated by a transparent medium layer, which can effectively reduce the size of the light-emitting pixels, so that it can be applied to fields such as AR, and the projections of multiple light-emitting units do not overlap with each other, avoiding mutual occlusion of different light-emitting units, thereby ensuring the display effect of the display panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 is a top view of a display panel provided by an embodiment of the present disclosure;

[0022] Figure 2 is a top view of a display unit in a display panel provided by an embodiment of the present disclosure;

[0023] Figure 3 is a schematic cross-sectional view of a display unit AA' in a display panel provided by an embodiment of the present disclosure;

[0024] Figure 4 is a schematic cross-sectional view of a display unit BB' in a display panel provided by an embodiment of the present disclosure;

[0025] Figure 5 is a schematic diagram of a CC' cross section of a display unit in a display panel provided by an embodiment of the present disclosure;

[0026] Figure 6 is a flow chart of a method for preparing a display panel provided by an embodiment of the present disclosure;

[0027] Figure 7 It is a flow chart of another display panel manufacturing method provided in an embodiment of the present disclosure.

[0028] The reference numerals are as follows:

[0029] 100: substrate; 200: light emitting unit; 300: transparent medium layer;

[0030] 201: first light-emitting unit; 202: second light-emitting unit; 203: third light-emitting unit; 301: first transparent medium layer; 302: second transparent medium layer; 303: third transparent medium layer; 401: first conductive column; 402: second conductive column; 403: third conductive column; 404: fourth conductive column; 405: fifth conductive column; 211: bonding metal layer; 212: epitaxial layer; 213: insulating layer; 214: electrode; 215: top electrode layer; 2121: first semiconductor layer; 2122: active layer; 2123: second semiconductor layer. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0032] Figure 1 is a top view of a display panel provided by an embodiment of the present disclosure. Figure 1 The integrated circuit board includes: a substrate 100, a plurality of light-emitting units 200 and a transparent medium layer 300.

[0033] A plurality of light emitting units 200 are arranged in an array on the substrate 100 , and each light emitting unit 200 is a pixel of the display panel.

[0034] Each light-emitting unit 200 includes at least a first light-emitting unit 201 of a first light-emitting color, a second light-emitting unit 202 of a second light-emitting color, and a third light-emitting unit 203 of a third light-emitting color. The first light-emitting unit 201, the second light-emitting unit 202, and the third light-emitting unit 203 are sequentially stacked on the substrate 100.

[0035] Figure 2 is a top view of a display unit in a display panel provided by an embodiment of the present disclosure. Figure 1 and Figure 2 , the projections of the first light emitting unit 201 , the second light emitting unit 202 and the third light emitting unit 203 on the substrate 100 do not overlap.

[0036] The transparent medium layer 300 includes a first transparent medium layer 301, a second transparent medium layer 302 and a third transparent medium layer 303. The first transparent medium layer 301 is located between the first light-emitting unit 201 and the second light-emitting unit 202, the second transparent medium layer 302 is located between the second light-emitting unit 202 and the third light-emitting unit 203, and the third transparent medium layer 303 covers the third light-emitting unit 203.

[0037] The first electrode of the first light emitting unit 201, the first electrode of the second light emitting unit 202 and the first electrode of the third light emitting unit 203 are electrically connected to the substrate 100 respectively, and the second electrode of the first light emitting unit 201, the second electrode of the second light emitting unit 202 and the second electrode of the third light emitting unit 203 are connected.

[0038] In the embodiment of the present disclosure, three light-emitting units are arranged on the substrate, and the three light-emitting units are not arranged in the same layer, but are arranged in a stacked manner and separated by a transparent medium layer, which can effectively reduce the size of the light-emitting pixel, so that it can be applied to fields such as AR, and the projections of multiple light-emitting units do not overlap with each other, avoiding mutual shading of different light-emitting units, thereby ensuring the display effect of the display panel. In the embodiment of the present disclosure, the first light-emitting unit 201 is a red light-emitting unit, the second light-emitting unit 202 is a green light-emitting unit, and the third light-emitting unit 203 is a blue light-emitting unit. Red, green and blue are the three primary colors. By setting red, green and blue light-emitting units, full-color display can be achieved.

[0039] In the embodiment of the present disclosure, the projection area of ​​the first light emitting unit 201 on the substrate 100 is larger than the projection area of ​​the second light emitting unit 202 on the substrate 100, and the projection area of ​​the first light emitting unit 201 on the substrate 100 is larger than the projection area of ​​the third light emitting unit 203 on the substrate 100. The red light emitting efficiency is most affected by the chip size. The smaller the size, the lower the efficiency. A large size can improve the red light emitting efficiency.

[0040] In other implementations, the light-emitting unit 200 may include other light-emitting units in addition to the first to third display units, such as a fourth light-emitting unit, and the fourth light-emitting unit may be a green light-emitting unit.

[0041] In the embodiment of the present disclosure, the display panel further includes: a top electrode layer 215, the top electrode layer 215 is disposed on the surface of the third transparent medium layer 303, and the second electrode of the first light-emitting unit 201, the second electrode of the second light-emitting unit 202, and the second electrode of the third light-emitting unit 203 are electrically connected to the top electrode layer 215. The light-emitting unit is electrically connected to the top electrode layer through the second electrode to form electrical conduction, thereby ensuring the stability of the electrical connection.

[0042] Figure 3 It is a schematic cross-sectional diagram of a display unit AA' in a display panel provided by an embodiment of the present disclosure. Figure 4 It is a schematic cross-sectional diagram of a display unit taken along line BB' in a display panel provided by an embodiment of the present disclosure. Figure 5 It is a schematic cross-sectional diagram of a display unit CC' in a display panel provided by an embodiment of the present disclosure.

[0043] See also Figures 3 to 5The first electrode of the first light-emitting unit 201 is directly electrically connected to the substrate 100, the first electrode of the second light-emitting unit 202 is electrically connected to the substrate 100 through the first transparent medium layer 301 via the first conductive column 401, and the first electrode of the third light-emitting unit 203 is electrically connected to the substrate 100 through the first transparent medium layer 301 and the second transparent medium layer 302 via the second conductive column 402.

[0044] In this implementation, the light-emitting unit is electrically connected to the substrate by passing the conductive column through the dielectric layer, so that different light-emitting units are prevented from blocking each other, thereby ensuring the display effect of the display panel and the stability of the electrical connection.

[0045] See also Figures 3 to 5 The second electrode of the first light-emitting unit 201 is electrically connected to the second electrode of the second light-emitting unit 202 through the third conductive column 403 passing through the first transparent medium layer 301, the second electrode of the second light-emitting unit 202 is electrically connected to the second electrode of the third light-emitting unit 203 through the fourth conductive column 404 passing through the second transparent medium layer 302, and the second electrode of the third light-emitting unit 203, the fifth conductive column 405, extends from the third transparent medium layer 303.

[0046] In this implementation, the second electrodes of a plurality of light-emitting units in one pixel are electrically connected by a conductive column passing through the dielectric layer, thereby facilitating subsequent wiring.

[0047] During control, the same voltage signal is applied to the second electrodes of multiple light-emitting units in the same pixel, and different voltage signals are applied to the first electrodes of multiple light-emitting units in the same pixel through the substrate to control the brightness of multiple light-emitting units in the same pixel, thereby achieving a ratio of red, green and blue light, so that the pixel displays different brightness and colors.

[0048] Optionally, the substrate 100 is electrically connected through the second electrode of the first light emitting unit 201 , the second electrode of the second light emitting unit 202 , and the second electrode of the third light emitting unit 203 .

[0049] In this implementation, the light-emitting unit achieves electrical conduction by being electrically connected to the substrate, thereby ensuring the stability of the electrical connection.

[0050] See also Figures 3 to 5 The first light-emitting unit 201, the second light-emitting unit 202 and the third light-emitting unit 203 each include: a bonding metal layer 211 and an epitaxial layer 212 stacked in sequence, an insulating layer 213 covering the bonding metal layer 211 and the epitaxial layer 212, and an electrode 214 connected to the epitaxial layer 212 through the insulating layer 213. The bonding metal layer ensures that the epitaxial layer can be bonded to the substrate and the bonding metal layer can form an electrical connection.

[0051] In the embodiment of the present disclosure, the bonding metal layer 211 serves as a first electrode of the light emitting unit 200 , and the electrode 214 serves as a second electrode of the plurality of light emitting units 200 .

[0052] In this implementation, the light-emitting unit has a simple structure, and the bonding layer facilitates the manufacture of the stacked display panel.

[0053] In the embodiment of the present disclosure, the second electrode of the first light emitting unit 201, the second electrode of the second light emitting unit 202 and the second electrode of the third light emitting unit 203 are in the shape of a long strip. The long strip electrode facilitates electrical connection between the electrode and the substrate, thereby improving electrical performance.

[0054] In other examples, the shape of the second electrode may also be other shapes, such as a circle.

[0055] In the embodiment of the present disclosure, the second electrode of the first light emitting unit 201, the second electrode of the second light emitting unit 202 and the second electrode of the third light emitting unit 203 are connected to the center of the light emitting unit 200. Connecting the second electrodes of multiple light emitting units to the center can simplify the circuit design and enhance the overall light uniformity and brightness.

[0056] In the embodiment of the present disclosure, the substrate 100 is a complementary metal-oxide-semiconductor (CMOS) substrate.

[0057] Exemplarily, the CMOS substrate includes a thin film transistor circuit, and the thin film transistor is used as a switch to control the on and off of each light emitting unit and the current size.

[0058] In the embodiment of the present disclosure, the epitaxial layer 212 includes a first semiconductor layer 2121 , an active layer 2122 , and a second semiconductor layer 2123 which are sequentially stacked.

[0059] In the embodiment of the present disclosure, the first semiconductor layer 2121 may be an N-type semiconductor layer, the second semiconductor layer 2123 may be a P-type semiconductor layer, and the active layer 2122 may be a multi-quantum well layer.

[0060] For example, the first semiconductor layer 2121 of the first light-emitting unit 201 may be an N-type AlInGaP layer, the second semiconductor layer 2123 may be a P-type AlInGaP layer, and the active layer 2122 may include a plurality of periodically alternating stacked AlInGaP quantum well layers and AlInGaP quantum barrier layers; the first semiconductor layer 2121 of the second light-emitting unit 202 and the third light-emitting unit 203 may be an N-type GaN layer, the second semiconductor layer 2123 may be a P-type GaN layer, and the active layer 2122 may be an InGaN / GaN multiple quantum well structure.

[0061] In another example, the first semiconductor layer 2121 may be a P-type semiconductor layer, and the second semiconductor layer 2123 may be an N-type semiconductor layer. The active layer 2122 may be a multi-quantum well layer.

[0062] In the embodiment of the present disclosure, the bonding metal layer 211 may be an Au or Au alloy layer, which can ensure the bonding effect on the one hand, and the conductive performance on the other hand.

[0063] In the embodiment of the present disclosure, the insulating layer 213 may be a SiO 2 layer.

[0064] In the embodiment of the present disclosure, the electrode 214 may be an indium tin oxide (ITO) electrode.

[0065] In the embodiment of the present disclosure, the first transparent medium layer 301 , the second transparent medium layer 302 and the third transparent medium layer 303 may be SiO 2 layers.

[0066] In the embodiment of the present disclosure, the first conductive pillar 401 , the second conductive pillar 402 , the third conductive pillar 403 , the fourth conductive pillar 404 , and the fifth conductive pillar 405 may be conductive pillars of dock metal.

[0067] Optionally, the first light-emitting unit 201 , the second light-emitting unit 202 and the third light-emitting unit 203 may further include: an ohmic contact layer, wherein the ohmic contact layer is disposed between the bonding metal layer 211 and the epitaxial layer 212 .

[0068] Optionally, the first light-emitting unit 201 , the second light-emitting unit 202 and the third light-emitting unit 203 may further include: an electrode metal layer. The electrode metal layer is disposed between the bonding metal layer 211 and the epitaxial layer 212 .

[0069] The above-mentioned light-emitting unit film layer structure is only an example. In other implementations, the light-emitting unit film may further include more or fewer film layers.

[0070] See again Figures 3 to 5 In the embodiment of the present disclosure, the insulating layer 213 covers the sidewalls of the epitaxial layer and the bonding metal layer, and extends on the substrate or the transparent dielectric layer.

[0071] The electrode 214 may extend from the top of the epitaxial layer to the insulating layer 213 on the substrate or the transparent dielectric layer, and the conductive pillars (403-405) are connected to the electrode 214 on the insulating layer 213 extending to the substrate or the transparent dielectric layer.

[0072] See again Figures 3 to 5In the embodiment of the present disclosure, the first conductive pillar 401 and the second conductive pillar 402 are staggered with each other; the third conductive pillar 403, the fourth conductive pillar 404 and the fifth conductive pillar 405 are connected to each other in a straight line, and the fourth conductive pillar 404 is staggered with the first conductive pillar 401 and the second conductive pillar 402.

[0073] See again Figures 3 to 5 The tops of the third conductive pillar 403 , the fourth conductive pillar 404 and the fifth conductive pillar 405 have a connecting portion for interconnecting the conductive pillars.

[0074] Figure 6 is a flow chart of a method for manufacturing a display panel provided by an embodiment of the present disclosure. Figure 6 The method steps include:

[0075] S11. Provide a substrate.

[0076] S12. Make a plurality of light-emitting units and a transparent medium layer on the substrate, wherein the plurality of light-emitting units are arranged in an array on the substrate, each of the light-emitting units comprises a first light-emitting unit, a second light-emitting unit and a third light-emitting unit, the first light-emitting unit, the second light-emitting unit and the third light-emitting unit are sequentially stacked on the substrate, and the projections of the first light-emitting unit, the second light-emitting unit and the third light-emitting unit on the substrate do not overlap; the transparent medium layer comprises a first transparent medium layer, a second transparent medium layer and a third transparent medium layer, the first transparent medium layer is located between the first light-emitting unit and the second light-emitting unit, the second transparent medium layer is located between the second light-emitting unit and the third light-emitting unit, and the third transparent medium layer covers the third light-emitting unit; the first electrode of the first light-emitting unit, the first electrode of the second light-emitting unit and the first electrode of the third light-emitting unit are electrically connected to the substrate respectively, the second electrode of the first light-emitting unit, the second electrode of the second light-emitting unit and the second electrode of the third light-emitting unit are connected and extend from the third transparent medium layer.

[0077] In the embodiment of the present disclosure, each of the multiple light-emitting units on the substrate includes at least three light-emitting units with different light-emitting colors, and color display can be achieved through the three light-emitting units; at the same time, the three light-emitting units are not arranged in the same layer, but are arranged in a stacked manner and separated by a transparent medium layer, which can effectively reduce the size of the light-emitting pixels, so that it can be applied to fields such as AR, and the projections of multiple light-emitting units do not overlap with each other, avoiding mutual occlusion of different light-emitting units, thereby ensuring the display effect of the display panel.

[0078] Figure 7 is a flow chart of another method for manufacturing a display panel provided by an embodiment of the present disclosure. Figure 7 The method steps include:

[0079] S21. Provide a substrate.

[0080] In the embodiment of the present disclosure, the substrate 100 is a complementary metal-oxide-semiconductor (CMOS) substrate.

[0081] Exemplarily, the CMOS substrate includes a thin film transistor circuit, and the thin film transistor is used as a switch to control the on and off of each light emitting unit and the current size.

[0082] S22, bonding a first epitaxial film layer on the substrate.

[0083] In one example, step S22 includes:

[0084] In the first step, a bonding metal film layer is deposited on the substrate.

[0085] In the embodiment of the present disclosure, the bonding metal layer may be an Au or Au alloy layer, which can ensure the bonding effect on the one hand and the conductive performance on the other hand.

[0086] The second step is to fabricate an epitaxial film layer and a bonding metal film layer of the first light-emitting unit on a temporary substrate.

[0087] In the embodiment of the present disclosure, the temporary substrate may be a GaAs substrate.

[0088] In the embodiment of the present disclosure, the epitaxial layer of the first light emitting unit includes a first semiconductor layer, an active layer and a second semiconductor layer.

[0089] In the embodiment of the present disclosure, the first semiconductor layer may be an N-type semiconductor layer, and the second semiconductor layer may be a P-type semiconductor layer.

[0090] For example, the first semiconductor layer may be an N-type AlInGaP layer, and the second semiconductor layer may be a P-type AlInGaP layer.

[0091] In another example, the first semiconductor layer may be a P-type semiconductor layer, and the second semiconductor layer may be an N-type semiconductor layer.

[0092] In the embodiment of the present disclosure, the active layer may be a multi-quantum well layer, for example, the multi-quantum well layer may include a plurality of periodically alternately stacked AlInGaP quantum well layers and AlInGaP quantum barrier layers.

[0093] The third step is to bond the epitaxial layer and the substrate of the first light-emitting unit together through a bonding metal film layer and remove the temporary substrate.

[0094] In the embodiment of the present disclosure, the first light emitting unit may be a red light emitting unit.

[0095] S23, performing patterning on the first epitaxial film layer to form a plurality of epitaxial layers of the first light-emitting units, wherein the epitaxial layers of the first light-emitting units are electrically connected to the substrate.

[0096] Exemplarily, the first epitaxial film layer and the bonding metal film layer are etched to obtain an epitaxial layer and a bonding metal layer.

[0097] S24. Fabricate an insulating layer of the first light-emitting unit, wherein the insulating layer of the first light-emitting unit covers the epitaxial layer of the first light-emitting unit.

[0098] In one example, step S24 includes:

[0099] The first step is to deposit an insulating film layer.

[0100] In the embodiment of the present disclosure, the insulating film layer may be made of SiO2 material.

[0101] The second step is to pattern the insulating film layer and open conductive through holes.

[0102] In the embodiment of the present disclosure, the insulating layer is opened at the middle position of the epitaxial layer of the first light-emitting unit.

[0103] S25. Fabricate an electrode of the first light-emitting unit, wherein the electrode of the first light-emitting unit passes through the insulating layer of the first light-emitting unit and is connected to the epitaxial layer of the first light-emitting unit.

[0104] In one example, step S25 includes:

[0105] In the first step, an indium tin oxide (ITO) layer is deposited and connected to the epitaxial layer of the first light-emitting unit through a conductive through hole.

[0106] The second step is to pattern the ITO and remove excess ITO to obtain the electrode of the first light-emitting unit.

[0107] S26. Manufacturing a first transparent medium layer, wherein the first transparent medium layer covers the insulating layer of the first light-emitting unit and the electrode of the first light-emitting unit.

[0108] In the embodiment of the present disclosure, the first transparent medium layer may be a SiO2 layer.

[0109] In the embodiment of the present disclosure, the thickness of the first transparent medium layer is greater than the thickness of the epitaxial layer of the first light-emitting unit, thereby achieving the purpose of planarization.

[0110] In the disclosed embodiment, the first transparent medium layer is polished by chemical mechanical polishing (CMP) to form a flat surface.

[0111] S27, manufacturing a first conductive column and a third conductive column passing through the first transparent medium layer, wherein the first conductive column is electrically connected to the substrate, and the third conductive column is electrically connected to the electrode of the first light-emitting unit.

[0112] In the embodiment of the present disclosure, the first conductive pillar and the third conductive pillar may be conductive pillars of docking metal.

[0113] In one example, step S27 includes:

[0114] In the first step, two through holes are opened on the first transparent medium layer.

[0115] In the second step, tungsten metal is deposited to form a first conductive column and a third conductive column.

[0116] S28. Bonding a second epitaxial film layer on the first transparent medium layer.

[0117] In one example, step S28 includes:

[0118] In the first step, a bonding metal film layer is deposited on the first transparent medium layer.

[0119] In the embodiment of the present disclosure, the bonding metal layer may be an Au or Au alloy layer, which can ensure the bonding effect on the one hand and the conductive performance on the other hand.

[0120] The second step is to fabricate an epitaxial film layer and a bonding metal film layer of a second light emitting unit on a temporary substrate.

[0121] In the embodiment of the present disclosure, the temporary substrate may be a Si substrate or a sapphire substrate.

[0122] Exemplarily, the temporary substrate is a Si substrate.

[0123] In an embodiment of the present disclosure, the epitaxial layer of the second light emitting unit includes a first semiconductor layer, an active layer and a second semiconductor layer. In a possible implementation of the present disclosure, the first semiconductor layer is an N-type semiconductor layer, and the second semiconductor layer is a P-type semiconductor layer.

[0124] Exemplarily, the first semiconductor layer may be an N-type GaN layer, and the second semiconductor layer may be a P-type GaN layer.

[0125] In another possible implementation, the first semiconductor layer is a P-type semiconductor layer, and the second semiconductor layer is an N-type semiconductor layer.

[0126] Exemplarily, the first semiconductor layer is a P-type GaN layer, and the second semiconductor layer is an N-type GaN layer.

[0127] In the embodiment of the present disclosure, the active layer may be a multi-quantum well layer, such as an InGaN / GaN multi-quantum well structure.

[0128] The third step is to bond the epitaxial layer of the second light-emitting unit and the first transparent medium layer together through a bonding metal film layer, and remove the temporary substrate.

[0129] In the embodiment of the present disclosure, the second light emitting unit may be a green light emitting unit.

[0130] S29, performing patterning on the second epitaxial film layer to form a plurality of epitaxial layers of the second light-emitting units, wherein the epitaxial layers of the second light-emitting units are electrically connected to the first conductive pillars.

[0131] Exemplarily, the second epitaxial film layer and the bonding metal film layer are etched to obtain an epitaxial layer and a bonding metal layer.

[0132] S30, manufacturing an insulating layer of the second light-emitting unit, wherein the insulating layer of the second light-emitting unit covers the epitaxial layer of the second light-emitting unit.

[0133] In one example, step S30 includes:

[0134] The first step is to deposit an insulating film layer of the second light emitting unit.

[0135] In the embodiment of the present disclosure, the insulating film layer may be made of SiO2 material.

[0136] The second step is to pattern the insulating film layer and open conductive through holes.

[0137] In the embodiment of the present disclosure, a hole is formed in the insulating layer at the middle position of the epitaxial layer of the second light-emitting unit.

[0138] S31. Fabricate an electrode of the second light-emitting unit, wherein the electrode of the second light-emitting unit passes through the insulating layer of the second light-emitting unit and is connected to the epitaxial layer of the second light-emitting unit.

[0139] In one example, step S31 includes:

[0140] In the first step, an indium tin oxide (ITO) layer is deposited and connected to the epitaxial layer of the second light-emitting unit through a conductive through hole.

[0141] The second step is to pattern the ITO and remove excess ITO to obtain the electrode of the second light-emitting unit.

[0142] S32. Manufacturing a second transparent medium layer, wherein the second transparent medium layer covers the insulating layer of the second light-emitting unit and the electrode of the second light-emitting unit.

[0143] In the embodiment of the present disclosure, the second transparent medium layer may be a SiO2 layer.

[0144] In the embodiment of the present disclosure, the thickness of the second transparent medium layer is greater than the thickness of the epitaxial layer of the second light emitting unit, thereby achieving the purpose of planarization.

[0145] In the disclosed embodiment, the second transparent medium layer is subjected to CMP polishing to form a flat surface.

[0146] S33, manufacturing a fourth conductive column passing through the second transparent medium layer and a second conductive column passing through the first transparent medium layer and the second transparent medium layer, wherein the second conductive column is electrically connected to the substrate, and the fourth conductive column is electrically connected to the electrode of the second light-emitting unit.

[0147] In the embodiment of the present disclosure, the fourth conductive pillar may be a conductive pillar of docking metal.

[0148] In one example, step S33 includes:

[0149] In the first step, two through holes are opened on the second transparent medium layer.

[0150] In the second step, tungsten metal is deposited to form a second conductive column and a fourth conductive column.

[0151] S34, bonding a third epitaxial film layer on the second transparent medium layer.

[0152] In one example, step S34 includes:

[0153] In the first step, a bonding metal film layer is deposited on the second transparent medium layer.

[0154] In the embodiment of the present disclosure, the bonding metal layer may be Au.

[0155] Or Au alloy layer, on the one hand, can ensure the bonding effect, on the other hand, can ensure the conductive performance.

[0156] The second step is to fabricate an epitaxial film layer and a bonding metal film layer of the third light-emitting unit on a temporary substrate.

[0157] In the embodiment of the present disclosure, the temporary substrate may be a Si substrate or a sapphire substrate.

[0158] Exemplarily, the temporary substrate is a Si substrate.

[0159] In the embodiment of the present disclosure, the epitaxial layer of the third light emitting unit includes a first semiconductor layer, an active layer and a second semiconductor layer.

[0160] In a possible implementation of the present disclosure, the first semiconductor layer is an N-type semiconductor layer, and the second semiconductor layer is a P-type semiconductor layer.

[0161] Exemplarily, the first semiconductor layer may be an N-type GaN layer, and the second semiconductor layer may be a P-type GaN layer.

[0162] In another possible implementation, the first semiconductor layer is a P-type semiconductor layer, and the second semiconductor layer is an N-type semiconductor layer.

[0163] Exemplarily, the first semiconductor layer is a P-type GaN layer, and the second semiconductor layer is an N-type GaN layer.

[0164] In the embodiment of the present disclosure, the active layer may be a multi-quantum well layer, such as an InGaN / GaN multi-quantum well structure.

[0165] In the third step, the epitaxial layer of the third light-emitting unit and the second transparent medium layer are bonded together through a bonding metal film layer, and the temporary substrate is removed.

[0166] In the embodiment of the present disclosure, the third light emitting unit is a blue light emitting unit.

[0167] S35, performing patterning on the third epitaxial film layer to form a plurality of epitaxial layers of the third light-emitting units, wherein the epitaxial layers of the third light-emitting units are electrically connected to the second conductive pillars.

[0168] Exemplarily, the third epitaxial film layer and the bonding metal film layer are etched to obtain an epitaxial layer and a bonding metal layer.

[0169] S36, manufacturing an insulating layer of the third light-emitting unit, wherein the insulating layer of the third light-emitting unit covers the epitaxial layer of the third light-emitting unit.

[0170] In one example, step S36 includes:

[0171] The first step is to deposit an insulating film layer of the third light-emitting unit.

[0172] In the embodiment of the present disclosure, the insulating layer of the third light emitting unit may be made of SiO2 material.

[0173] The second step is to pattern the insulating film layer and open conductive through holes.

[0174] In the embodiment of the present disclosure, a hole is formed in the insulating layer at the middle position of the epitaxial layer of the third light-emitting unit.

[0175] S37, manufacturing an electrode of the third light-emitting unit, wherein the electrode of the third light-emitting unit passes through the insulating layer of the third light-emitting unit and is connected to the epitaxial layer of the third light-emitting unit.

[0176] In one example, step S37 includes:

[0177] In the first step, an indium tin oxide (ITO) layer is deposited and connected to the epitaxial layer of the third light-emitting unit through a conductive through hole.

[0178] The second step is to pattern the ITO and remove excess ITO to obtain the electrode of the third light-emitting unit.

[0179] S38. Prepare a third transparent medium layer, wherein the third transparent medium layer covers the insulating layer of the third light-emitting unit and the electrode of the third light-emitting unit.

[0180] In the embodiment of the present disclosure, the third transparent medium layer may be a SiO2 layer.

[0181] In the embodiment of the present disclosure, the thickness of the third transparent medium layer is greater than the thickness of the epitaxial layer of the third light emitting unit, thereby achieving the purpose of planarization.

[0182] In the disclosed embodiment, the third transparent medium layer is subjected to CMP polishing to form a flat surface.

[0183] S39, manufacturing a fifth conductive column passing through the third transparent medium layer, wherein the fifth conductive column is electrically connected to the electrode of the third light-emitting unit.

[0184] In one example, step S39 includes:

[0185] In the first step, two through holes are opened on the third transparent medium layer.

[0186] In the second step, tungsten metal is deposited to form the fifth conductive column.

[0187] S40, manufacturing a top electrode layer, wherein the top electrode layer is disposed on the surface of the third transparent medium layer, and the second electrode of the first light-emitting unit, the second electrode of the second light-emitting unit, and the second electrode of the third light-emitting unit are electrically connected to the top electrode layer.

[0188] The above description is only an optional embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A display panel, characterized in that: The display panel comprises: a substrate (100), a plurality of light-emitting units (200) and a transparent medium layer (300); The plurality of light-emitting units (200) are arranged in an array on the substrate (100), each of the light-emitting units (200) comprises at least a first light-emitting unit (201) of a first light-emitting color, a second light-emitting unit (202) of a second light-emitting color, and a third light-emitting unit (203) of a third light-emitting color, the first light-emitting unit (201), the second light-emitting unit (202), and the third light-emitting unit (203) are sequentially stacked on the substrate (100), and the projections of the first light-emitting unit (201), the second light-emitting unit (202), and the third light-emitting unit (203) on the substrate (100) do not overlap; The transparent medium layer (300) comprises a first transparent medium layer (301), a second transparent medium layer (302) and a third transparent medium layer (303), wherein the first transparent medium layer (301) is located between the first light-emitting unit (201) and the second light-emitting unit (202), the second transparent medium layer (302) is located between the second light-emitting unit (202) and the third light-emitting unit (203), and the third transparent medium layer (303) covers the third light-emitting unit (203); The first electrode of the first light-emitting unit (201), the first electrode of the second light-emitting unit (202), and the first electrode of the third light-emitting unit (203) are respectively electrically connected to the substrate (100), and the second electrode of the first light-emitting unit (201), the second electrode of the second light-emitting unit (202), and the second electrode of the third light-emitting unit (203) are connected.

2. The display panel according to claim 1, characterized in that: The display panel further comprises: a top electrode layer (215), wherein the top electrode layer (215) is arranged on the surface of the third transparent medium layer (303), and the second electrode of the first light-emitting unit (201), the second electrode of the second light-emitting unit (202) and the second electrode of the third light-emitting unit (203) are electrically connected to the top electrode layer (215).

3. The display panel according to claim 1, characterized in that: The second electrode of the first light-emitting unit (201), the second electrode of the second light-emitting unit (202), and the second electrode of the third light-emitting unit (203) are electrically connected to the substrate (100).

4. The display panel according to any one of claims 1 to 3, characterized in that: The first light-emitting unit (201) is a red light-emitting unit, the second light-emitting unit (202) is a green light-emitting unit, and the third light-emitting unit (203) is a blue light-emitting unit.

5. The display panel according to claim 4, characterized in that: The projection area of ​​the first light-emitting unit (201) on the substrate (100) is greater than the projection area of ​​the second light-emitting unit (202) on the substrate (100), and the projection area of ​​the first light-emitting unit (201) on the substrate (100) is greater than the projection area of ​​the third light-emitting unit (203) on the substrate (100).

6. The display panel according to any one of claims 1 to 3, characterized in that: The first electrode of the first light-emitting unit (201) is directly electrically connected to the substrate (100), the first electrode of the second light-emitting unit (202) is electrically connected to the substrate (100) through the first transparent medium layer (301) via a first conductive column (401), and the first electrode of the third light-emitting unit (203) is electrically connected to the substrate (100) through the first transparent medium layer (301) and the second transparent medium layer (302) via a second conductive column (402).

7. The display panel according to any one of claims 1 to 3, characterized in that: The second electrode of the first light-emitting unit (201) is electrically connected to the second electrode of the second light-emitting unit (202) through the third conductive column (403) passing through the first transparent medium layer (301); the second electrode of the second light-emitting unit (202) is electrically connected to the second electrode of the third light-emitting unit (203) through the fourth conductive column (404) passing through the second transparent medium layer (302); and the second electrode of the third light-emitting unit (203) extends from the third transparent medium layer (303) through a fifth conductive column (405).

8. The display panel according to any one of claims 1 to 3, characterized in that: The first light-emitting unit (201), the second light-emitting unit (202) and the third light-emitting unit (203) all include: a bonding metal layer (211) and an epitaxial layer (212) stacked in sequence, an insulating layer (213) covering the bonding metal layer (211) and the epitaxial layer (212), and an electrode (214) passing through the insulating layer (213) and connected to the epitaxial layer (212).

9. The display panel according to any one of claims 1 to 3, characterized in that: The second electrode of the first light-emitting unit (201), the second electrode of the second light-emitting unit (202) and the second electrode of the third light-emitting unit (203) are in the shape of elongated strips.

10. The display panel according to claim 9, characterized in that: The second electrode of the first light-emitting unit (201), the second electrode of the second light-emitting unit (202), and the second electrode of the third light-emitting unit (203) are connected to the center of the light-emitting unit (200).

Images