Display device and manufacturing method thereof

Abstract

The invention provides a display device and a manufacturing method thereof, the display device comprises a plurality of display pixels, each display pixel comprises at least one first light-emitting unit, and the first light-emitting unit comprises a first light-emitting diode and a color conversion layer. The first light-emitting diode is arranged on the substrate and comprises a first connecting pad, a first semiconductor layer, a first light-emitting layer, a second semiconductor layer and a second connecting pad which are sequentially arranged in a stacked mode. The color conversion layer surrounds the first light emitting diode. The top surface of the color conversion layer is lower than the top surface of the second connecting pad, or is coplanar with the top surface of the second connecting pad.

Description

Technical Field

[0001] The invention relates to a display device and a manufacturing method thereof. Background Art

[0002] The process of LED display includes multiple die flipping. During the flipping process, a colloid layer is used to fix the die, and the colloid layer needs to be removed at the end. In addition, if a color conversion layer is required for color conversion, after the die is transferred to the backplane, additional process configurations must be performed. Figure 1 A colloidal layer 201A containing color conversion particles is shown. Summary of the invention

[0003] The invention provides a display device and a manufacturing method thereof, which can significantly shorten the process time.

[0004] According to one embodiment of the present invention, a display device is provided, comprising a substrate and a plurality of display pixels arranged on the substrate, wherein each display pixel comprises a plurality of light-emitting units. The light-emitting units comprise at least one first light-emitting unit, the first light-emitting unit comprising a first light-emitting diode and a color conversion layer. The first light-emitting diode is arranged on the substrate, and comprises a first pad, a first semiconductor layer, a first light-emitting layer, a second semiconductor layer and a second pad arranged in a stacked order, wherein the first pad is connected to the first semiconductor layer, and the second pad is connected to the second semiconductor layer. The color conversion layer surrounds the first light-emitting diode. The top surface of the color conversion layer is lower than the top surface of the second pad, or is coplanar with the top surface of the second pad.

[0005] According to one embodiment of the present invention, a method for manufacturing a display device is provided, including sequentially configuring a second semiconductor layer, a light-emitting layer, a first semiconductor layer and a first pad on a temporary substrate, wherein the first pad is connected to the first semiconductor layer; sequentially configuring a glue layer and a substrate on the temporary substrate, wherein the glue layer includes color conversion particles and surrounds the light-emitting layer, and the substrate is bonded to the first pad; removing the temporary substrate; configuring a second pad on the second semiconductor layer; and completing the first light-emitting unit.

[0006] Based on the above, the display device manufacturing method provided by the embodiment of the present invention configures color conversion particles in the glue layer used to fix the first light-emitting diode, so there is no need to remove the glue layer during the manufacturing process. The glue layer can be used as the color conversion layer of the display device, and no additional process is required to configure the color conversion layer. Compared with the prior art, the process time is greatly shortened.

[0007] In order to make the above features and advantages of the present invention more obvious and easy to understand, embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a schematic diagram of a light emitting unit according to the prior art.

[0009] FIG. 2A to FIG. 2D A schematic diagram showing a method for manufacturing a display device according to an embodiment of the present invention is shown.

[0010] FIG. 3A to FIG. 3C shows a schematic diagram of a light emitting unit according to some embodiments of the present invention, Figure 3D A graph showing the relative reflectivity of light on different components.

[0011] Figure 4 Schematic diagram showing a light emitting unit according to some embodiments of the present invention.

[0012] Figure 5 Schematic diagram showing a light emitting unit according to some embodiments of the present invention.

[0013] Fig. 6A shows a schematic diagram of a light emitting unit according to some embodiments of the present invention, Figure 6B A schematic diagram showing a display pixel of a display device provided according to an embodiment of the present invention is shown.

[0014] Figure 7 A schematic diagram showing a display pixel of a display device provided according to an embodiment of the present invention is shown.

[0015] Description of reference numerals:

[0016] 1, 2, 3, 4: Light-emitting units

[0017] 01: Temporary substrate

[0018] 10: Substrate

[0019] 100: First light emitting diode

[0020] 100P: Protective layer

[0021] 101: First semiconductor layer

[0022] 101P: First pad

[0023] 102: Second semiconductor layer

[0024] 102P: Second pad

[0025] 103: Luminous layer

[0026] 200: Second light emitting diode

[0027] 201: Adhesive layer, color conversion layer

[0028] 201A: Color conversion layer

[0029] 201P: Color conversion particles

[0030] 201T: Top

[0031] 203: Luminous layer

[0032] 301: Distributed Bragg Reflector

[0033] 302: Color blocking layer

[0034] 401, 501: Transparent conductive layer

[0035] 402: Conductive layer

[0036] 500, 600: Display device DETAILED DESCRIPTION

[0037] Reference FIG. 2A to FIG. 2D , which sequentially show schematic diagrams of a method for manufacturing a display device according to an embodiment of the present invention.

[0038] like Figure 2A As shown, the second semiconductor layer 102 , the light emitting layer 103 , the first semiconductor layer 101 and the first pad 101P are sequentially arranged on the temporary substrate 01 , wherein the first pad 101P is connected to the first semiconductor layer 101 .

[0039] like Figure 2B As shown, a glue layer 201 is disposed on the temporary substrate 01 to fix the second semiconductor layer 102, the light emitting layer 103, the first semiconductor layer 101 and the first pad 101P. It should be particularly noted that the glue layer 201 includes color conversion particles 201P; and the substrate 10 is disposed on the first pad 101P and the glue layer 201, wherein the first pad 101P is bonded to the substrate 10.

[0040] like Figure 2C As shown, flip Figure 2B and remove the temporary substrate 01.

[0041] like Figure 2D As shown, a second pad 102P is disposed on the second semiconductor layer 102 to form a light-emitting unit 1. The area of ​​the vertical projection of the second pad 102P on the second semiconductor layer 102 is not zero. The light-emitting unit 1 includes a first light-emitting diode 100 and a glue layer 201 surrounding the first light-emitting diode 100. The first light-emitting diode 100 includes a first pad 101P, a first semiconductor layer 101, a light-emitting layer 103, a second semiconductor layer 102, and a second pad 102P.

[0042] It should be noted that, compared to the prior art, the display device manufacturing method according to this embodiment does not need to remove the glue layer 201 used to fix the first light emitting diode 100, nor does it need other processes for configuring the color conversion layer, which greatly shortens the process time compared to the prior art. Figure 2D As shown in FIG. 1 , since the glue layer 201 surrounds the first light-emitting diode 100, the light emitted from the light-emitting layer 103 can be color-converted by the color-converting particles 201P in the glue layer 201. In other words, the glue layer 201 can be used as the color-converting layer (i.e., the color-converting layer 201) of the first light-emitting diode 100. It should also be noted that, through the above FIG. 2A to FIG. 2D In the manufacturing method shown, the top surface 201T of the color conversion layer 201 away from the substrate 10 is coplanar with the top surface of the second semiconductor layer 102 away from the substrate 10 and is lower than the top surface of the second pad 102P away from the substrate 10 .

[0043] However, the present invention is not limited thereto. In some embodiments not shown, Figure 2D The top surface 201T shown is provided with a glue layer made of the same material as the color conversion layer 201, so as to increase the thickness of the color conversion layer 201 and improve the color conversion rate. In these embodiments, the top surface of the color conversion layer 201 away from the substrate 10 can be coplanar with the top surface of the second pad 102P away from the substrate 10. In some embodiments not shown, part of the color conversion layer 201 can be removed so that the top surface of the color conversion layer 201 away from the substrate 10 is lower than the top surface of the second semiconductor layer 102 away from the substrate 10.

[0044] Through the display device manufacturing method provided by the above embodiment, some embodiments of the present invention provide a display device, which includes a plurality of display pixels, and each display pixel may include a plurality of light-emitting units, at least one of the light-emitting units may be as follows Figure 2D The light-emitting unit 1 shown includes a first light-emitting diode 100 and a color conversion layer 201 surrounding the first light-emitting diode 100, wherein each first light-emitting diode 100 includes a first pad 101P, a first semiconductor layer 101, a light-emitting layer 103, a second semiconductor layer 102, and a second pad 102P. In some embodiments, a top surface 201T of the color conversion layer 201 away from the substrate 10 may be coplanar with a top surface of the second semiconductor layer 102 away from the substrate 10, and lower than a top surface of the second pad 102P away from the substrate 10. In some embodiments, a top surface of the color conversion layer 201 away from the substrate 10 may be coplanar with a top surface of the second pad 102P away from the substrate 10. In some embodiments, a top surface of the color conversion layer 201 away from the substrate 10 may be lower than a top surface of the second semiconductor layer 102 away from the substrate 10. It should be noted that in order to ensure that all light emitted by the light-emitting layer 103 can be converted in color by the color conversion layer 201, the top surface of the second semiconductor layer 102 away from the substrate 10 is completely covered by the second pad 102P. Accordingly, the second pad 102P can reflect the light emitted by the light-emitting layer 103 and not passing through the color conversion layer 201, thereby improving the color conversion rate and ensuring the display quality of the display device.

[0045] In some embodiments, the light emitting layer 103 in the light emitting unit 1 can emit blue light, and the color conversion layer 201 is suitable for converting blue light into red light or green light. In these embodiments, each display pixel can include at least one light emitting unit without the color conversion layer 201 for emitting blue light.

[0046] In some embodiments, the light emitting layer 103 can emit ultraviolet light, and the color conversion layer 201 is suitable for converting the ultraviolet light into red light, green light or blue light.

[0047] In order to fully illustrate the various embodiments of the present invention, other embodiments of the present invention will be described below. It must be noted that the following embodiments use the component numbers and some contents of the previous embodiments, wherein the same numbers are used to represent the same or similar components, and the description of the same technical contents is omitted. For the description of the omitted parts, please refer to the previous embodiments, and the following embodiments will not be repeated.

[0048] Please refer to the following FIG. 3A to FIG. 3D , FIG. 3A to FIG. 3C shows a schematic diagram of a light emitting unit according to some embodiments of the present invention, Figure 3D A graph showing the relative reflectivity of light on different components.

[0049] Compared to Figure 2D The light emitting unit 1 shown in FIG. Figure 3A In the light-emitting unit 1 shown, a distributed Bragg reflector 301 is arranged on a portion of the top surface of the second semiconductor layer 102 away from the substrate 10 and on a top surface 201T of the color conversion layer 201 away from the substrate 10, wherein the distributed Bragg reflector 301 is suitable for reflecting light emitted from the light-emitting layer 103 and not passing through the color conversion layer 201, and allowing light emitted from the light-emitting layer 103 and having passed through the color conversion layer 201 for color conversion to pass through.

[0050] Please refer to Figure 3D , wherein Curve I shows the relative reflectivity of light of different wavelengths when reflected on the second pad 102P made of gold (Au), and Curve II shows the relative reflectivity of light of different wavelengths when reflected on the distributed Bragg reflector 301. It can be seen that when the blue light band is reflected on the second pad 102P made of gold (Au), the blue light band has a lower reflectivity than the other color light bands. In addition, since the distributed Bragg reflector 301 utilizes the interference phenomenon caused by layers with different refractive indices to enhance the reflectivity, the distributed Bragg reflector 301 has the disadvantage of lower reflectivity for light incident at a large angle. Please also refer to Figure 3B as well as Figure 3D Compared to Figure 3A The light emitting unit 1, in Figure 3B In the light emitting unit 1 shown, a distributed Bragg reflector 301 is disposed on a portion of the top surface of the second semiconductor layer 102 away from the substrate 10 and on a top surface 201T of the color conversion layer 201 away from the substrate 10, and the distributed Bragg reflector 301 overlaps the second pad 102P on the portion of the top surface of the second semiconductor layer 102. Figure 3D Curve III shows the relative reflectivity of light of different wavelengths in the above overlapping area. It can be seen that light in the visible light band has a higher reflectivity in the above overlapping area. In other words, Figure 3B The light emitting unit 1 shown can effectively prevent the light emitted from the light emitting layer 103 and not passing through the color conversion layer 201 from emitting upward through the distributed Bragg reflector 301 and the second pad 102P, thereby improving the color conversion rate and ensuring the display quality of the display device.

[0051] Compared to Figure 3A The light emitting unit 1 shown in FIG. Figure 3C In the light-emitting unit 1 shown, a color-blocking layer 302 is also provided on the side of the color conversion layer 201. The color-blocking layer 302 corresponds to the color conversion layer 201 and filters the light that is color-converted by the color conversion layer 201 to further ensure the display quality of the display device. In addition, by providing the color-blocking layer 302 on the side of the color conversion layer 201, there is no need to provide a bank between the light-emitting unit 1 and the light-emitting units of other adjacent colors in the display device.

[0052] Please refer to Figure 4 , which shows a schematic diagram of a light-emitting unit according to some embodiments of the present invention. Figure 2D The light emitting unit 1 shown in FIG. Figure 4 In the light-emitting unit 1 shown, a color-resistance layer 302 is disposed on the top surface 201T of the color conversion layer 201 away from the substrate 10, on the side of the color conversion layer 201, on the top surface of the second pad 102P away from the substrate 10, and on the side of the second pad 102P, wherein the color-resistance layer 302 corresponds to the color conversion layer 201 to further filter light and ensure the display quality of the display device. By disposing the color-resistance layer 302 on the side of the color conversion layer 201, it is not necessary to dispose a bank between the light-emitting unit 1 and the light-emitting units of other colors adjacent to the display device.

[0053] Please refer to Figure 5 , which shows a schematic diagram of a light-emitting unit according to some embodiments of the present invention. Figure 2D The light emitting unit 1 shown in FIG. Figure 5In the light-emitting unit 1 shown, a distributed Bragg reflector 301 is disposed on a portion of the top surface of the second semiconductor layer 102 away from the substrate 10, on a top surface 201T of the color conversion layer 201 away from the substrate 10, and on the side of the color conversion layer 201, wherein the distributed Bragg reflector 301 is adapted to reflect light emitted from the light-emitting layer 103 and not passing through the color conversion layer 201, and to allow light emitted from the light-emitting layer 103 and color-converted by the color conversion layer 201 to pass through. In addition, a color-blocking layer 302 is further disposed on a surface of the distributed Bragg reflector 301 away from the color conversion layer 201, wherein the color-blocking layer 302 corresponds to the color conversion layer 201, and the color-blocking layer 302 is adapted to filter light that is color-converted by the color conversion layer 201 and penetrates the distributed Bragg reflector 301, so as to further ensure the display quality of the display device. In addition, by disposing the distributed Bragg reflector 301 and the color resist layer 302 on the side of the color conversion layer 201 , no bank is required between the light emitting unit 1 and the light emitting units of other adjacent colors in the display device.

[0054] Reference Fig. 6A , which shows a schematic diagram of a light-emitting unit according to some embodiments of the present invention. Figure 5 The light emitting unit 1 shown in FIG. Fig. 6A In the light emitting unit 1 shown, a color resist layer 302 is disposed on the side of the color conversion layer 201, but no distributed Bragg reflector 301 is disposed. Figure 6B , which shows a schematic diagram of a display pixel of a display device 500 provided according to an embodiment of the present invention. The display device 500 includes a plurality of display pixels, and each display pixel may include a light emitting unit 1, a light emitting unit 3, and a light emitting unit 4, wherein the light emitting unit 1 may be composed of Fig. 6A The light emitting unit 1 shown is used for implementation. However, the present invention is not limited thereto. Figure 6B The light emitting unit 1 in the embodiment can also be composed of Figure 2D , Figure 3A , Figure 3B , Figure 3C , Figure 4 as well as Figure 5 The light emitting unit 1 shown in any one of the above is implemented. Figure 6B In the embodiment, the light emitting unit 3 and the light emitting unit 4 do not include a color conversion layer. In some embodiments, the light emitting unit 1 can be used to generate red light, the light emitting unit 3 can be used to generate green light, and the light emitting unit 4 can be used to generate blue light, but the present invention is not limited thereto. It should be noted that since the color blocking layer 302 is provided on the side of the color conversion layer 201 of the light emitting unit 1, crosstalk between the light emitting unit 1 and other adjacent light emitting units of other colors in the display device 500 (for example, the light emitting unit 3) can be avoided, and a dam may not be provided between the two light emitting units.

[0055] Reference Figure 7, which shows a schematic diagram of a display pixel of a display device 600 provided according to an embodiment of the present invention. The display device 600 includes a plurality of display pixels, and each display pixel may include two light-emitting units 1 and two light-emitting units 2 respectively located on the two light-emitting units 1, wherein the two light-emitting units 1 may be composed of Figure 2D , Figure 3A , Figure 3B , Figure 3C , Figure 4 , Figure 5 as well as Fig. 6A The light-emitting unit 1 shown in any one of the two light-emitting units 2 is implemented, and any one of the two light-emitting units 2 has a second light-emitting diode 200 with a structure similar to the aforementioned first light-emitting diode 100, and the second light-emitting diode 200 includes a light-emitting layer 203, and the second light-emitting diode 200 in each light-emitting unit 2 is not surrounded by the color conversion layer 201.

[0056] In an exemplary embodiment, the color conversion layer 201 in each light emitting unit 1 is suitable for converting the blue light emitted by the light emitting layer 103 surrounding it into red light. One of the two light emitting units 2 can emit blue light, and the other can emit green light. The distributed Bragg reflector 301 in the light emitting unit 1 is suitable for reflecting blue light and green light.

[0057] In an exemplary embodiment, the color conversion layer 201 in each light emitting unit 1 is suitable for converting the blue light emitted by the light emitting layer 103 surrounding it into green light. One of the two light emitting units 2 can emit blue light, and the other can emit red light. The distributed Bragg reflector 301 in the light emitting unit 1 is suitable for reflecting blue light and red light.

[0058] It should be noted that compared with the prior art in which the light-emitting unit 1 and the light-emitting unit 2 are arranged at the same horizontal height, the present embodiment greatly increases the space utilization by stacking the light-emitting unit 2 on the light-emitting unit 1, thereby reducing the area occupied by each display pixel on the substrate 10 and improving the resolution of the display device 600.

[0059] It should also be noted that if Figure 7 As shown, the vertical projection of the light-emitting layer 203 on the substrate 10 overlaps the vertical projection of the light-emitting layer 103 on the substrate 10, and at least a portion of the vertical projection of the light-emitting layer 203 on the substrate 10 does not overlap the vertical projection of the color conversion layer 201 on the substrate 10. Accordingly, the light-emitting layer 203 of the light-emitting unit 2 will not block the light from the color conversion layer 201, and the distributed Bragg reflector 301 in the light-emitting unit 1 is suitable for reflecting the light emitted by the light-emitting layer 203 of the light-emitting unit 2, thereby reducing energy loss. In addition, since the color blocking layer 302 is provided on the side of the color conversion layer 201 of the light-emitting unit 1, a bank may not be provided between the light-emitting unit 1 and other adjacent light-emitting units.

[0060] It should be noted that the display device 600 is a single-board structure, which can be completed by sequentially configuring a plurality of light-emitting units 1, a transparent conductive layer 401, a plurality of light-emitting units 2, and a conductive layer 402 on a substrate 10. The transparent conductive layer 401 is used as a common electrode layer for each light-emitting unit 1 and each light-emitting unit 2, and the conductive layer 402 can be a transparent conductive layer or a metal layer, and is electrically connected to the substrate 10. In another embodiment, the light-emitting units 1 and the light-emitting units 2 can be combined in a double-board pairing manner, not in a single board pairing manner. Figure 7 The structures shown are limited.

[0061] In summary, the display device manufacturing method provided by the embodiment of the present invention configures color conversion particles in the glue layer used to fix the first light-emitting diode, so there is no need to remove the glue layer during the manufacturing process. The glue layer can be used as the color conversion layer of the display device, and no additional process is required to configure the color conversion layer. Compared with the prior art, the process time is greatly shortened.

Claims

1. A display device, comprising a substrate and a plurality of display pixels arranged on the substrate, wherein each of the display pixels comprises a plurality of light-emitting units, the plurality of light-emitting units comprises at least one first light-emitting unit, and the at least one first light-emitting unit comprises: A first light emitting diode is disposed on the substrate and includes a first pad, a first semiconductor layer, a first light emitting layer, a second semiconductor layer and a second pad which are sequentially stacked, wherein the first pad is connected to the first semiconductor layer, and the second pad is connected to the second semiconductor layer; as well as A color conversion layer surrounds the first light emitting diode, wherein The top surface of the color conversion layer is lower than the top surface of the second pad, or is coplanar with the top surface of the second pad. 2 . The display device of claim 1 , wherein the top surface of the color conversion layer is coplanar with a top surface of the second semiconductor layer. The display device of claim 1 , wherein the top surface of the color conversion layer is lower than a top surface of the second semiconductor layer. The display device as claimed in claim 1 , wherein a color resist layer is disposed on at least one surface of the color conversion layer. 5 . The display device as claimed in claim 1 , wherein a distributed Bragg reflector is disposed on at least one surface of the color conversion layer. 6 . The display device as claimed in claim 5 , wherein the distributed Bragg reflector is disposed on a top surface of the second semiconductor layer. 7 . The display device as claimed in claim 6 , wherein the DBR and the second pad are overlapped. 8 . The display device as claimed in claim 7 , wherein a color resist layer is disposed on at least one surface of the color conversion layer, and the DBR is located between the color conversion layer and the color resist layer.

9. The display device of claim 1, wherein the first light emitting layer emits blue light.

10. The display device of claim 1, wherein the first light emitting layer emits ultraviolet light. 11 . The display device as claimed in claim 1 , wherein the plurality of light emitting units include at least one second light emitting unit, and the at least one second light emitting unit is disposed on the at least one first light emitting unit. 12 . The display device as claimed in claim 11 , wherein the at least one second light-emitting unit comprises a second light-emitting layer, and a vertical projection of the second light-emitting layer on the substrate overlaps a vertical projection of the first light-emitting layer of the at least one first light-emitting unit on the substrate.

13. The display device as claimed in claim 11, wherein the at least one second light-emitting unit comprises a second light-emitting layer, and at least a portion of the vertical projection of the second light-emitting layer on the substrate does not overlap the vertical projection of the color conversion layer of the at least one first light-emitting unit on the substrate.

14. A method for manufacturing a display device, comprising: A second semiconductor layer, a light emitting layer, a first semiconductor layer and a first pad are sequentially arranged on a temporary substrate, wherein the first pad is connected to the first semiconductor layer; sequentially disposing a glue layer and a substrate on the temporary substrate, wherein the glue layer includes color conversion particles and surrounds the light-emitting layer, and the substrate is bonded to the first pad; removing the temporary substrate; disposing a second pad on the second semiconductor layer; and The first light-emitting unit is completed.

15. The method for manufacturing a display device according to claim 14, further comprising: Disposing a transparent conductive layer on the first light-emitting unit; as well as A second light emitting unit is disposed on the transparent conductive layer, wherein the transparent conductive layer is a common electrode layer of the first light emitting unit and the second light emitting unit.

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