Micro Light Emitting Diode Package Structure

Abstract

To provide a micro light-emitting diode package structure that can increase the luminous efficacy of the micro light-emitting diode package structure, improve its contrast, and reduce its size.SOLUTION: A micro light-emitting diode package structure includes a redistribution layer, a control device, micro light-emitting diodes, and a flexible material layer. The redistribution layer has a first side face, and a second side face opposite to the first side face. The control device and the micro light-emitting diodes are disposed on the redistribution layer and electrically connected to the redistribution layer. The flexible material layer covers the control device and the micro light-emitting diodes, and the micro light-emitting diodes are in contact with the flexible material layer. The control device is disposed on the first side face of the redistribution layer, and the micro light-emitting diodes are disposed on the second side face of the redistribution layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a micro light-emitting diode packaging structure, and more particularly to a micro light-emitting diode packaging structure that integrates a control device and a micro light-emitting diode. [Background technology]

[0002] 2. Description of the Related Art Light emitting diodes (LEDs) have the advantage of low power consumption, so LED displays have become the mainstream in the display technology field. Summary of the Invention [Problem to be solved by the invention]

[0003] However, since it is difficult to further reduce the thickness and size of the LED itself, the current packaging technology makes it difficult to achieve the goal of small pitch size and low cost. Therefore, there is a need for further improving the light emitting diode package structure and the method for forming the same to produce a light emitting diode display device that meets manufacturing requirements. [Means for solving the problem]

[0004] One embodiment of the present invention provides a micro light-emitting diode packaging structure, which includes a redistribution layer, a control device, a micro light-emitting diode, and a flexible material layer. The redistribution layer includes a first side, and the first Side and The opposite is the second Side The control device and the micro light-emitting diodes are disposed on the redistribution layer and electrically connected to the redistribution layer. A flexible material layer covers the control device and the micro light-emitting diodes, and the micro light-emitting diodes are in contact with the flexible material layer. The control device is attached to a first portion of the redistribution layer. On the side The micro light-emitting diode is provided in the second redistribution layer. On the sideThe control device and the micro light-emitting diodes are arranged side by side in a horizontal direction, and at least one of the rear surfaces of the micro light-emitting diodes has a rough surface. Furthermore, the redistribution layer has an outwardly extending portion, which is characterized in that the outwardly extending portion forms an electrical connection between the anodes and common cathode of the plurality of micro light-emitting diodes and an external circuit. [Effects of the Invention]

[0005] The light emitting efficiency of the micro LED package structure can be increased, the contrast can be improved, and the size can be further reduced. [Brief explanation of the drawings]

[0006] The present invention may be more fully understood by reference to the following detailed description and examples taken in conjunction with the accompanying drawings, in which: [Figure 1] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 2] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 3] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 4] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 5] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 6] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 7] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 8] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 9] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 10]1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 11] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 12] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 13] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 14] 1A and 1B are cross-sectional views of micro light-emitting diode packaging structures according to some embodiments of the present invention. [Figure 15] FIG. 2 is a bottom view of a micro light-emitting diode packaging structure according to some embodiments of the present invention, illustrating the relationship between the area (AD) of the distributed Bragg reflector (DBR) layer and the total area (AT) of the micro light-emitting diode packaging structure. [Figure 16] 1 is a cross-sectional view of a micro light-emitting diode in a micro light-emitting diode packaging structure according to some embodiments of the present invention, illustrating the shape of the back surface of the micro light-emitting diode. [Figure 17A] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 17B] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 17C] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 17D] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 17E] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 17F]2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 17G] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 17H] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 17I] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 17J] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 17K] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 18A] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 18B] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 18C] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 18D] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 18E] 2A-2D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 1 according to some embodiments of the present invention. [Figure 19A] 3A-3C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 2 according to some embodiments of the present invention. [Figure 19B]3A-3C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 2 according to some embodiments of the present invention. [Figure 19C] 3A-3C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 2 according to some embodiments of the present invention. [Figure 19D] 3A-3C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 2 according to some embodiments of the present invention. [Figure 19E] 3A-3C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 2 according to some embodiments of the present invention. [Figure 19F] 3A-3C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 2 according to some embodiments of the present invention. [Figure 19G] 3A-3C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 2 according to some embodiments of the present invention. [Figure 19H] 3A-3C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 2 according to some embodiments of the present invention. [Figure 19I] 3A-3C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 2 according to some embodiments of the present invention. [Figure 19J] 3A-3C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 2 according to some embodiments of the present invention. [Figure 20A] 4A-4D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 3 according to some embodiments of the present invention. [Figure 20B] 4A-4D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 3 according to some embodiments of the present invention. [Figure 20C] 4A-4D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 3 according to some embodiments of the present invention. [Figure 20D]4A-4D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 3 according to some embodiments of the present invention. [Figure 20E] 4A-4D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 3 according to some embodiments of the present invention. [Figure 20F] 4A-4D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 3 according to some embodiments of the present invention. [Figure 20G] 4A-4D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 3 according to some embodiments of the present invention. [Figure 20H] 4A-4D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 3 according to some embodiments of the present invention. [Figure 20I] 4A-4D are cross-sectional views illustrating different stages in forming the micro light-emitting diode packaging structure of FIG. 3 according to some embodiments of the present invention. [Figure 21A] 5A-5C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 4 according to some embodiments of the present invention. [Figure 21B] 5A-5C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 4 according to some embodiments of the present invention. [Figure 21C] 5A-5C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 4 according to some embodiments of the present invention. [Figure 21D] 5A-5C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 4 according to some embodiments of the present invention. [Figure 21E] 5A-5C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 4 according to some embodiments of the present invention. [Figure 21F] 5A-5C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 4 according to some embodiments of the present invention. [Figure 21G]5A-5C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 4 according to some embodiments of the present invention. [Figure 21H] 5A-5C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 4 according to some embodiments of the present invention. [Figure 21I] 5A-5C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 4 according to some embodiments of the present invention. [Figure 22A] 6A-6C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 5 according to some embodiments of the present invention. [Figure 22B] 6A-6C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 5 according to some embodiments of the present invention. [Figure 22C] 6A-6C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 5 according to some embodiments of the present invention. [Figure 22D] 6A-6C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 5 according to some embodiments of the present invention. [Figure 22E] 6A-6C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 5 according to some embodiments of the present invention. [Figure 22F] 6A-6C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 5 according to some embodiments of the present invention. [Figure 22G] 6A-6C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 5 according to some embodiments of the present invention. [Figure 22H] 6A-6C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 5 according to some embodiments of the present invention. [Figure 22I] 6A-6C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 5 according to some embodiments of the present invention. [Figure 23A]7A-7C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 6 according to some embodiments of the present invention. [Figure 23B] 7A-7C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 6 according to some embodiments of the present invention. [Figure 23C] 7A-7C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 6 according to some embodiments of the present invention. [Figure 23D] 7A-7C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 6 according to some embodiments of the present invention. [Figure 23E] 7A-7C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 6 according to some embodiments of the present invention. [Figure 23F] 7A-7C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 6 according to some embodiments of the present invention. [Figure 23G] 7A-7C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 6 according to some embodiments of the present invention. [Figure 23H] 7A-7C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 6 according to some embodiments of the present invention. [Figure 24A] 8A-8C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 7 according to some embodiments of the present invention. [Figure 24B] 8A-8C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 7 according to some embodiments of the present invention. [Figure 24C] 8A-8C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 7 according to some embodiments of the present invention. [Figure 24D] 8A-8C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 7 according to some embodiments of the present invention. [Figure 24E]8A-8C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 7 according to some embodiments of the present invention. [Figure 24F] 8A-8C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 7 according to some embodiments of the present invention. [Figure 24G] 8A-8C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 7 according to some embodiments of the present invention. [Figure 24H] 8A-8C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 7 according to some embodiments of the present invention. [Figure 25A] 9A-9C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 8 according to some embodiments of the present invention. [Figure 25B] 9A-9C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 8 according to some embodiments of the present invention. [Figure 25C] 9A-9C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 8 according to some embodiments of the present invention. [Figure 25D] 9A-9C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 8 according to some embodiments of the present invention. [Figure 26A] 10A-10C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 9 according to some embodiments of the present invention. [Figure 26B] 10A-10C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 9 according to some embodiments of the present invention. [Figure 26C] 10A-10C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 9 according to some embodiments of the present invention. [Figure 26D] 10A-10C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 9 according to some embodiments of the present invention. [Figure 26E]10A-10C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 9 according to some embodiments of the present invention. [Figure 26F] 10A-10C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 9 according to some embodiments of the present invention. [Figure 26G] 10A-10C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 9 according to some embodiments of the present invention. [Figure 27A] 11A-11C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 10 according to some embodiments of the present invention. [Figure 27B] 11A-11C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 10 according to some embodiments of the present invention. [Figure 27C] 11A-11C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 10 according to some embodiments of the present invention. [Figure 27D] 11A-11C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 10 according to some embodiments of the present invention. [Figure 28A] 12A-12C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 11 according to some embodiments of the present invention. [Figure 28B] 12A-12C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 11 according to some embodiments of the present invention. [Figure 28C] 12A-12C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 11 according to some embodiments of the present invention. [Figure 28D] 12A-12C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 11 according to some embodiments of the present invention. [Figure 28E] 12A-12C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 11 according to some embodiments of the present invention. [Figure 28F]12A-12C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 11 according to some embodiments of the present invention. [Figure 29A] 13A-13C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 12 according to some embodiments of the present invention. [Figure 29B] 13A-13C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 12 according to some embodiments of the present invention. [Figure 29C] 13A-13C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 12 according to some embodiments of the present invention. [Figure 29D] 13A-13C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 12 according to some embodiments of the present invention. [Figure 29E] 13A-13C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 12 according to some embodiments of the present invention. [Figure 30A] 14A-14C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 13 according to some embodiments of the present invention. [Figure 30B] 14A-14C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 13 according to some embodiments of the present invention. [Figure 30C] 14A-14C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 13 according to some embodiments of the present invention. [Figure 31A] 15A-15C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 14 according to some embodiments of the present invention. [Figure 31B] 15A-15C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 14 according to some embodiments of the present invention. [Figure 31C] 15A-15C are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure of FIG. 14 according to some embodiments of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0007] The following description explains the best mode for carrying out the present invention. This description is made for the purpose of explaining the general principles of the present invention and should not be taken in a limiting sense. The thicknesses of layers and regions in the drawings have been exaggerated for clarity, and the same or similar reference numerals in each drawing represent the same or similar elements.

[0008] Some embodiments of the present invention provide a micro light-emitting diode packaging structure and a method for forming the same, which integrates a controller and a micro light-emitting diode into the same packaging structure to form a pixel package, which is individually / independently controlled and reduces the volume of the packaging structure, and is applied to small-pitch displays, such as wearable display devices or special totem micro light sources.

[0009] 1-14 illustrate a micro light emitting diode (LED) packaging structure 500 according to some embodiments of the present invention, including micro light emitting diode (LED) packaging structures 500a-500i, 500k-500n, and 500p. FIG. 1 is a cross-sectional view of the micro light emitting diode packaging structure 500a according to some embodiments of the present invention. The micro light emitting diode packaging structure 500a includes a redistribution layer (RDL) 220, a controller 212, a micro light emitting diode 205 (including micro light emitting diodes 206, 208, and 210), and a flexible material layer 250. 1 , the redistribution layer 220 has a first side 220-1 and a second side 220-2 opposite to each other, and is disposed on the micro light-emitting diodes 206, 208, 210, and the controller 212, and is electrically connected to the micro light-emitting diodes 206, 208, 210, and the controller 212. The redistribution layer 220 reroutes the original positions of the electrical nodes of the micro light-emitting diodes 205 and the controller 212 to designated positions in the micro light-emitting diode package structure using fan-out routing. In some embodiments, the redistribution layer 220 includes a stack of conductive material layers, for example, chromium (Cr), aluminum (Al), nickel (Ni), gold (Au), platinum (Pt), tin (Sn), copper (Cu), or a combination thereof, and the redistribution layer 220 is formed using a plating process such as evaporation or electroplating.

[0010] 1 , the control device 212 and the micro light-emitting diodes 205, which are spaced apart from each other, are disposed side by side on the first side 220-1 of the redistribution layer 220 and are electrically connected to the redistribution layer 220. The control device 212 has a contact pad 212p and a back surface 212b located away from the contact pad 212p. In addition, the micro light-emitting diodes 206, 208, and 210 have electrodes 206p, 208p, and 210p and back surfaces 206b, 208b, and 210b located away from the electrodes 206p, 208p, and 210p, respectively. In some embodiments, the back surfaces 206b, 208b, and 210b of the micro light-emitting diodes 206, 208, and 210 are also light-emitting surfaces of the micro light-emitting diodes 206, 208, and 210. The redistribution layer 220 is disposed on the electrodes 206p, 208p, 210p of the micro light-emitting diodes 206, 208, 210 and the contact pads 212p of the controller 212, and is in contact with the electrodes 206p, 208p, 210p of the micro light-emitting diodes 206, 208, 210 and the contact pads 212p of the controller 212. In some embodiments, the rear surface 212b of the controller 212 is flush with the rear surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210. In some embodiments, the controller 212 includes a micro-driver integrated circuit (IC) device, a micro-control integrated circuit (IC) device, or a combination thereof. In some embodiments, the micro light-emitting diode 205 has micro light-emitting diodes 206, 208, 210 that emit light of different wavelengths to form pixel units. For example, the micro light-emitting diodes 205 that emit different colored light include a micro light-emitting diode 206 that emits red light, a micro light-emitting diode 208 that emits green light, and a micro light-emitting diode 210 that emits blue light, although some embodiments of the present invention are not so limited.In some embodiments, the micro LED 205 has micro LEDs 206, 208, and 210 that emit light of the same wavelength, for example, blue light or ultraviolet (UV) light, and are coated with different phosphors or quantum dot materials, respectively, to absorb the light emitted from the micro LEDs 206, 208, and 210 and convert it into red light, green light, or blue light to form a pixel unit.

[0011] 1 , the flexible material layer 250 covers and contacts the back surface 212b of the control device 212 and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210. An interface 251 between the control device and the flexible material layer 250 is located away from the electrodes of the micro light-emitting diodes 206, 208, 210. An emitting surface 260 of the micro light-emitting diode package structure 500a is on the surface opposite the flexible material layer 250 and the interface 251. In some embodiments, the flexible material layer 250 includes a flexible material having good light transmittance (e.g., light transmittance greater than 90%), such as poly(methyl methacrylate) (PMMA), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polystyrene (PS), polypropylene (PP), polyamide (PA), polycarbonate (PC), polyimide (PI), epoxy, silicone, polydimethylsiloxane (PDMS), or a combination of any two or more of the above materials, and is formed in the form of, for example, a film paste, spray coating, etc.

[0012] 1 , the micro light-emitting diode package structure 500a further includes an insulating layer 216 disposed between the first side 220-1 of the re-distribution layer 220 and the flexible material layer 250. The insulating layer 216 contacts the re-distribution layer 220 and the flexible material layer 250. In addition, the insulating layer 216 surrounds the controller 212 and the micro light-emitting diodes 206, 208, 210, and covers the electrodes 206p, 208p, 210p and the contact pads 212p to provide electrical insulation between the controller 212 and the micro light-emitting diodes 206, 208, 210. 1, the redistribution layer 220 passes through a portion of the insulating layer 216 located above the controller 212 and the micro light-emitting diodes 206, 208, 210 to electrically connect to the electrodes 206p, 208p, 210p of the micro light-emitting diodes 206, 208, 210 and the contact pads 212p of the controller 212. As shown in FIG. 1, the back surface 212b of the controller 212 and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210 are exposed from the insulating layer 216. In some embodiments, the height of the insulating layer 216 between the redistribution layer 220 and the flexible material layer 250 is greater than the height of the micro light-emitting diodes 206, 208, 210 and the controller 212 to provide suitable electrical insulation. In some embodiments, the insulating layer 216 comprises an insulating material with a low dielectric constant and suitable step coverage, such as polyimide (PI), epoxy, or benzocyclobutene (BCB), and is formed by a coating process, such as spin coating or spray coating.

[0013] As shown in FIG. 1 , the micro light-emitting diode package structure 500a further includes an insulating layer 222 and a bonding pad 224, which serve as interconnect structures. As shown in FIG. 1 , the insulating layer 222 is disposed on the second side 220-2 of the re-distribution layer 220 and covers the re-distribution layer 220, serving as an electrically insulating feature between the re-distribution layers 220. As shown in FIG. 1 , the bonding pad 224 is disposed on the insulating layer 222, penetrates the insulating layer 222, and is electrically connected to the re-distribution layer 220 and used for electrically connecting to an external circuit. In some embodiments, the insulating layer 216 and the insulating layer 222 have the same or similar materials and processes. In some embodiments, the bonding pad 224 and the re-distribution layer 220 have the same or similar materials and formation processes.

[0014] 2 is a cross-sectional view of a micro light-emitting diode package structure 500b according to some embodiments of the present invention, in which the same or similar element reference numerals as those in FIG. 1 represent the same or similar elements. As shown in FIG. 2, the difference between the micro light-emitting diode package structure 500b and the micro light-emitting diode package structure 500a is that the micro light-emitting diode package structure 500b has a light-shielding layer 236 disposed between the redistribution layer 220 and the flexible material layer 250 to improve the contrast of the micro light-emitting diode package structure 500b. As shown in FIG. 2, the light-shielding layer 236 contacts the insulating layer 216 and the flexible material layer 250, surrounds the micro light-emitting diodes 206, 208, 210, and is adjacent to the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210. When the micro LEDs 206, 208, and 210 emit light from their rear surfaces 206b, 208b, and 210b, the light-shielding layer 236 includes a black matrix. In some embodiments, the light-shielding layer 236 includes a colloidal material and an inorganic material, where the colloidal material includes polymethylmethacrylate (PMMA), polycarbonate (PC), diethylene glycol bis(allyl carbonate) (CR-39), polystyrene (PS), epoxy, polyamide, acrylate, silicone, or a combination thereof. The inorganic material includes carbon powder, perovskite, or the like. In some embodiments, the light-shielding layer 236 includes another colloidal material and another organic material, where the organic material includes polyimide, polyvinyl alcohol resin, and / or acrylic resin doped with black pigment or dye. In some embodiments, the light-shielding layer 236 is formed by, for example, spin coating, casting, or the like.

[0015] 3 is a cross-sectional view of a micro light-emitting diode package structure 500c according to some embodiments of the present invention, in which the same or similar element reference numerals as those in FIGS. 1 and 2 represent the same or similar elements. As shown in FIG. 3, the difference between the micro light-emitting diode package structure 500c and the micro light-emitting diode package structure 500a is that the micro light-emitting diode package structure 500c includes a light-shielding layer 246 between the re-distribution layer 220 and the flexible material layer 250. As shown in FIG. 3, the light-shielding layer 246 is used to replace the insulating layer 216 of the micro light-emitting diode package structure 500a, which simultaneously provides electrical insulation and improves the contrast of the micro light-emitting diode package structure 500c. In some embodiments, the light-shielding layer 236 and the light-shielding layer 246 have the same or similar materials and formation processes.

[0016] 4 is a cross-sectional view of a micro light-emitting diode packaging structure 500d according to some embodiments of the present invention, in which the same or similar element symbols as those in FIGS. 1-3 represent the same or similar elements. As shown in FIG. 4, the difference between the micro light-emitting diode packaging structure 500d and the micro light-emitting diode packaging structure 500a is that the micro light-emitting diode packaging structure 500d has a distributed Bragg reflector (DBR) layer 240 in contact with the redistribution layer 220 and adjacent to the electrodes 206p, 208p, 210p of the micro light-emitting diodes 206, 208, 210, to improve the light-emitting efficiency of the micro light-emitting diode packaging structure 500d. In some embodiments, the distributed Bragg reflector layer 240 surrounds the micro light-emitting diodes 206, 208, 210 and extends along the sidewalls of the micro light-emitting diodes 206, 208, 210, and in contact with the electrodes 206p, 208p, 210p. The distributed Bragg reflector layer 240 contacts the redistribution layer 220 and the insulating layer 216, and the electrodes 206p, 208p, 210p of the micro light-emitting diodes 206, 208, 210 are exposed from the distributed Bragg reflector layer 240. The distributed Bragg reflector layer 240 separates the sidewalls of the micro light-emitting diodes 206, 208, 210 from the insulating layer 216. In some embodiments, the distributed Bragg reflector layer 240 is composed of alternating thin films of two or more homogeneous or heterogeneous materials with different refractive indices. For example, the distributed Bragg reflector layer 240 may be formed by alternating silicon dioxide (SiO) and titanium dioxide (TiO) layers, alternating silicon dioxide (SiO), aluminum oxide (AlO), and titanium dioxide (TiO), or alternating titanium dioxide (TiO), silicon dioxide (SiO), and tantalum pentoxide (TaO). In some embodiments, the distributed Bragg reflector layer 240 is formed by a deposition process, such as evaporation, atomic layer deposition (ALD), or metalorganic chemical vapor deposition (MOCVD), followed by a patterning process.

[0017] 5 is a cross-sectional view of a micro light-emitting diode packaging structure 500e according to some embodiments of the present invention, in which the same or similar element symbols as those in FIGS. 1 to 4 represent the same or similar elements. As shown in FIG. 5, the difference between the micro light-emitting diode packaging structure 500e and the micro light-emitting diode packaging structure 500a is that the micro light-emitting diode packaging structure 500e has a light-shielding layer 236 and a distributed Bragg reflector layer 240 disposed between the re-distribution layer 220 and the flexible material layer 250, thereby improving the contrast and light-emitting efficiency of the micro light-emitting diode packaging structure 500e. As shown in FIG. 5, the light-shielding layer 236 surrounds the micro light-emitting diodes 206, 208, and 210 and contacts the distributed Bragg reflector layer 240 extending along the sidewalls of the micro light-emitting diodes 206, 208, and 210. A distributed Bragg reflector layer 240 separates the micro light emitting diodes 206 , 208 , 210 from the insulating layer 216 and the light blocking layer 236 .

[0018] 6 is a cross-sectional view of a micro light-emitting diode packaging structure 500f according to some embodiments of the present invention, in which the same or similar element reference numerals as those in FIGS. 1-5 represent the same or similar elements. As shown in FIG. 6, the difference between the micro light-emitting diode packaging structure 500f and the micro light-emitting diode packaging structure 500c is that the micro light-emitting diode packaging structure 500f has a distributed Bragg reflector layer 240 surrounding the micro light-emitting diodes 206, 208, 210, further improving the light-emitting efficiency of the micro light-emitting diode packaging structure 500f. In some embodiments, the distributed Bragg reflector layer 240 separates the micro light-emitting diodes 206, 208, 210 from the light-shielding layer 246.

[0019] FIG. 7 is a cross-sectional view of a micro light-emitting diode packaging structure 500g according to some embodiments of the present invention, in which the same or similar element reference numerals as in FIGS. 1-6 represent the same or similar elements. As shown in FIG. 7, the micro light-emitting diode packaging structure 500g includes a re-distribution layer 320, a controller 312, a micro light-emitting diode 305 (including micro light-emitting diodes 306, 308, and 310), and a flexible material layer 350. In some embodiments, the controller 312 has the same or similar structure as the controller 212. The micro light-emitting diode 305 (including micro light-emitting diodes 306, 308, and 310) has the same or similar structure as the micro light-emitting diode 205 (including micro light-emitting diodes 206, 208, and 210). The re-distribution layer 320 has the same or similar material and formation method as the re-distribution layer 220. Flexible material layer 350 has the same or similar materials and methods of formation as flexible material layer 250 .

[0020] 7 , the difference between the micro light-emitting diode packaging structure 500a and the micro light-emitting diode packaging structure 500g is that the re-distribution layer 320 of the micro light-emitting diode packaging structure 500g has a first side 320-1 and a second side 320-2 opposite to each other. The control device 312 is disposed on the first side 320-1 of the re-distribution layer 320, and the micro light-emitting diodes 306, 308, and 310 are disposed on the second side 320-2 of the re-distribution layer 320. Specifically, the contact pad 312p of the control device 312 contacts the first side 320-1 of the re-distribution layer 320, and the electrodes 306p, 308p, and 310p of the micro light-emitting diodes 306, 308, and 310 contact the second side 320-2 of the re-distribution layer 320. The micro light emitting diodes 306, 308, 310 of the micro light emitting diode packaging structure 500g are closer to the light emitting surface 360 ​​of the micro light emitting diode packaging structure 500g than the control device 312.

[0021] 7, the insulating layer 316 is disposed on the first side 320-1 of the re-distribution layer 320 and contacts the control device 312. The insulating layer 316 is located between the re-distribution layer 320 and the control device 312. In addition, the re-distribution layer 320 penetrates a portion of the insulating layer 316 above the control device 312 and is electrically connected to the contact pads 312p of the control device 312. The back surface 312b of the control device 312 is located away from the contact pads 312p and is exposed through the insulating layer 316. In addition, the insulating layer 316 has an opening exposing the re-distribution layer 320 to electrically connect the re-distribution layer 320 to an external circuit. In some embodiments, the insulating layer 216 and the insulating layer 316 have the same or similar materials and formation methods.

[0022] As shown in FIG. 7 , the flexible material layer 350 of the micro light-emitting diode package structure 500g is disposed on the second side 320-2 of the re-distribution layer 320, covering and contacting the re-distribution layer 320, the sidewalls, electrodes 306p, 308p, 310p and backsides 306b, 308b, 310b of the micro light-emitting diodes 306, 308, 310, and the insulating layer 316 that is not covered by the re-distribution layer 320.

[0023] 7, the micro light-emitting diode package structure 500g further includes an adhesive layer 304R covering the back surface 312b of the control device 312. In some embodiments, the adhesive layer 304R includes an adhesive such as benzocyclobutene (BCB), polyimide (PI), epoxy, silicone, etc.

[0024] FIG. 8 is a cross-sectional view of a micro light-emitting diode packaging structure 500h according to some embodiments of the present invention, in which the same or similar element reference numerals as those in FIGS. 1-7 represent the same or similar elements. As shown in FIG. 8, the difference between the micro light-emitting diode packaging structure 500h and the micro light-emitting diode packaging structure 500g is that the micro light-emitting diode packaging structure 500h has a light-shielding layer 336 between the re-distribution layer 320 and the flexible material layer 350 to improve the contrast of the micro light-emitting diode packaging structure 500h. As shown in FIG. 8, the light-shielding layer 336 is disposed on the second side 320-2 of the re-distribution layer 320 and conformally covers the re-distribution layer 320. The light-shielding layer 336 contacts the insulating layer 316, the re-distribution layer 320, and the flexible material layer 350. The light-shielding layer 336 covers the control device 312 and surrounds the micro light-emitting diodes 306, 308, and 310. In addition, the light-shielding layer 336 is adjacent to the electrodes 306p, 308p, and 310p of the micro light-emitting diodes 306, 308, and 310. In some embodiments, the light-shielding layer 236 and the light-shielding layer 336 are made of the same or similar materials. The light-shielding layer 336 is formed using a coating process such as spin coating or spray coating.

[0025] 9 is a cross-sectional view of a micro light-emitting diode package structure 500i according to some embodiments of the present invention, in which the same or similar element reference numerals as those in FIGS. 1-8 represent the same or similar elements. As shown in FIG. 9, the difference between the micro light-emitting diode package structure 500g and the micro light-emitting diode package structure 500i is that the micro light-emitting diode package structure 500i includes a distributed Bragg reflector layer 340 adjacent to the electrodes 306p, 308p, and 310p of the micro light-emitting diodes 306, 308, and 310 and in contact with the re-distribution layer 320 to improve the light-emitting efficiency of the micro light-emitting diode package structure 500i. The distributed Bragg reflector layer 340 is located between the flexible material layer 350 and the insulating layer 316, conformally covers the insulating layer 316, and contacts the first side 320-1 of the re-distribution layer 320. Additionally, distributed Bragg reflector layer 340 partially covers control device 312. In some embodiments, distributed Bragg reflector layer 240 and distributed Bragg reflector layer 340 have the same or similar materials and formation methods.

[0026] 9, the micro light-emitting diode package structure 500i further includes a bonding pad 324. The bonding pad 324 is disposed between the insulating layer 316 and the distributed Bragg reflector layer 340 and is electrically connected to the re-distribution layer 320. The bonding pad 324 is exposed through an opening in the insulating layer 316 and is electrically connected to an external circuit. In some embodiments, the bonding pads 224 and 324 have the same or similar materials and formation methods.

[0027] 10 is a cross-sectional view of a micro LED packaging structure 500k according to some embodiments of the present invention, in which the same or similar elements as those in FIGS. 1 to 9 are designated by the same or similar reference numerals. As shown in FIG. 10, the difference between the micro LED packaging structure 500k and the micro LED packaging structure 500g is that the micro LED packaging structure 500k has a distributed Bragg reflector layer 340 disposed on the first side 320-1 of the redistribution layer 320 and a light-shielding layer 336 disposed on the second side 320-2 of the redistribution layer 320, thereby improving the contrast and light-emitting efficiency of the micro LED packaging structure 500e. As shown in FIG. 10, the distributed Bragg reflector layer 340 adjacent to the edge of the micro LED packaging structure 500k and the light-shielding layer 336 adjacent to the electrodes 306p, 308p, and 310p of the micro LEDs 306, 308, and 310 are in contact with each other.

[0028] FIG. 11 is a cross-sectional view of a micro light-emitting diode package structure 500l according to some embodiments of the present invention, in which the same or similar element reference numerals as those in FIGS. 1-10 represent the same or similar elements. As shown in FIG. 11 , the micro light-emitting diode package structure 500l includes a re-distribution layer 420, a controller 412, a micro light-emitting diode 405 (including micro light-emitting diodes 406, 408, and 410), and a flexible material layer 450. In some embodiments, the micro light-emitting diode 405 (including micro light-emitting diodes 406, 408, and 410) has the same or similar structure as the micro light-emitting diode 205 (including micro light-emitting diodes 206, 208, and 210) and the micro light-emitting diode 305 (including micro light-emitting diodes 306, 308, and 310). The re-distribution layer 420 has the same or similar structure and formation method as the re-distribution layers 220 and 320. Flexible material layer 450 has the same or similar materials and methods of formation as flexible material layers 250 and 350 .

[0029] 11 , the difference between the micro light-emitting diode packaging structure 500a and the micro light-emitting diode packaging structure 500l is that the re-distribution layer 420 of the micro light-emitting diode packaging structure 500l has a first side 420-1 and a second side 420-2 opposite to each other. The control device 412 is disposed on the first side 420-1 of the re-distribution layer 420, and the micro light-emitting diodes 406, 408, and 410 are disposed on the second side 420-2 of the re-distribution layer 420. Specifically, the control device 412 contacts and is electrically connected to the first side 420-1 of the re-distribution layer 420. The electrodes 406p, 408p, and 410p of the micro light-emitting diodes 406, 408, and 410 contact the second side 420-2 of the re-distribution layer 420. In addition, the micro light-emitting diodes 406, 408, and 410 of the micro light-emitting diode package structure 500l are located directly above and partially overlap the controller 412. As shown in FIG. 11 , the micro light-emitting diodes 406, 408, and 410 are closer to the light-emitting surface 460 of the micro light-emitting diode package structure 500l than the controller 412. In some embodiments, the controller 412 comprises a thin-film transistor device. In other embodiments, the controller 412 includes a micro-driver IC device, a micro-control IC device, or a combination thereof.

[0030] 11 , the insulating layer 416 is disposed on the first side 420-1 of the re-distribution layer 420 and contacts the control device 412. The insulating layer 416 covers the back surface 412b of the control device 412, so that the control device 412 is between the insulating layer 416 and the re-distribution layer 420. In addition, the control device 412 is located between the insulating layer 416 and the micro light-emitting diodes 406, 408, and 410. In addition, the insulating layer 416 has an opening exposing the re-distribution layer 420 to electrically connect the re-distribution layer 420 to an external circuit. In some embodiments, the insulating layer 416 functions as a support layer to support the control device 412, such as a thin film transistor device.

[0031] 11 , the flexible material layer 450 of the micro light-emitting diode package structure 500l is disposed on the second side 420-2 of the re-distribution layer 420, and covers and contacts the re-distribution layer 420, the sidewalls and backsides 406b, 408b, 410b of the micro light-emitting diodes 406, 408, 410, and the controller 412 that is not covered by the re-distribution layer 420. The flexible material layer 450 is separated from the insulating layer 416 by the controller 412 and the re-distribution layer 420.

[0032] 12 is a cross-sectional view of a micro light-emitting diode packaging structure 500m according to some embodiments of the present invention, in which the same or similar element reference numerals as those in FIGS. 1-11 represent the same or similar elements. As shown in FIG. 12, the difference between the micro light-emitting diode packaging structure 500m and the micro light-emitting diode packaging structure 500l is that the micro light-emitting diode packaging structure 500m further includes a distributed Bragg reflector layer 440 adjacent to the electrodes 406p, 408p, and 410p of the micro light-emitting diodes 406, 408, and 410 and in contact with the re-distribution layer 420 to increase the light-emitting efficiency of the micro light-emitting diode packaging structure 500m. The distributed Bragg reflector layer 440 is located between the flexible material layer 450 and the insulating layer 416, conformally covers the control device 412 and the insulating layer 416, and contacts the first side 420-1 of the re-distribution layer 420. In addition, the distributed Bragg reflector layer 440 partially covers the control device 412 .

[0033] FIG. 13 is a cross-sectional view of a micro light-emitting diode package structure 500n according to some embodiments of the present invention. In the drawing, the same or similar element reference numerals as those in FIGS. 1 to 12 represent the same or similar elements. As shown in FIG. 13, the difference between the micro light-emitting diode package structure 500n and the micro light-emitting diode package structure 500l is that the micro light-emitting diode package structure 500n further has a light shielding layer 436 between the redistribution layer 420 and the flexible material layer 450 to improve the contrast of the micro light-emitting diode package structure 500n. As shown in FIG. 13, the light shielding layer 436 is installed on the second side surface 420-2 of the redistribution layer 420 and conformally covers the redistribution layer 420. The light shielding layer 436 contacts the insulating layer 416, the redistribution layer 420, and the flexible material layer 450. The light shielding layer 436 surrounds the micro light-emitting diodes 406, 408, and 410 and covers the control device 412. In addition, the light shielding layer 436 is close to the electrodes 406p, 408p, and 410p of the micro light-emitting diodes 406, 408, and 410.

[0034] FIG. 14 is a cross-sectional view from the side of a micro light-emitting diode package structure 500p according to some embodiments of the present invention. In the drawing, the same or similar element reference numerals as those in FIGS. 1 to 13 represent the same or similar elements. As shown in FIG. 14, the difference between the micro light-emitting diode package structure 500p and the micro light-emitting diode package structure 500l is that the micro light-emitting diode package structure 500p further has a distributed Bragg reflector layer 440 installed on the first side surface 420-1 of the redistribution layer 420 and a light shielding layer 436 installed on the second side surface 420-2 of the redistribution layer 420 to simultaneously improve the contrast and light emission efficiency of the micro light-emitting diode package structure 500p. As shown in FIG. 14, the distributed Bragg reflector layer 440 and the light shielding layer 436, which are close to the ends of the micro light-emitting diode (LED) package structure 500p and the electrodes 406p, 408p, and 410p of the micro light-emitting diodes 406, 408, and 410, contact each other.

[0035] 15 is a bottom view of a micro light-emitting diode package structure 500 according to some embodiments of the present invention, illustrating the relationship between the area (AD) of the distributed Bragg reflector (DBR) layer and the total area (AT) of the top surface of the micro light-emitting diode package structure. FIG. 15 further illustrates the layout relationship between the redistribution layer (including redistribution layers 220, 320, and 420), the micro light-emitting diodes (including micro light-emitting diodes 205, 305, and 405), the control device (including control devices 212, 312, 412), and the distributed Bragg reflector layer (including distributed Bragg reflector layers 240, 340, and 440). The redistribution layer portions at the four corners of the micro light-emitting diode package structure 500 provide electrical connections between the anode and common cathode of each micro light-emitting diode and an external circuit, and are considered as bonding pads of the micro light-emitting diode package structure 500. In addition, the narrow redistribution layer portions between the bonding pad located at the upper left corner of the micro light-emitting diode packaging structure 500 and each micro light-emitting diode and control device are considered to be one of the conductive lines of the micro light-emitting diode packaging structure 500, simultaneously connecting the contact pad of the control device and the cathode of each micro light-emitting diode to the bonding pad located at the upper left corner of the micro light-emitting diode packaging structure 500. In addition, the narrow redistribution layer portions between the control device and the three bonding pads located at the upper right corner, lower right corner, and lower left corner of the micro light-emitting diode packaging structure 500 are respectively considered to be other conductive lines of the micro light-emitting diode packaging structure 500. The conductive lines can respectively connect the contact pad of the control device and the anode of each micro light-emitting diode to the three bonding pads located at the upper right corner, lower right corner, and lower left corner of the micro light-emitting diode packaging structure 500. As shown in FIG. 15 , in the plane of the bottom surface opposite to the light-emitting surface (e.g., light-emitting surfaces 260, 360, and 460) of the micro light-emitting diode packaging structure 500, the area AD of the distributed Bragg reflector layers 240, 340, and 440 is 10% to 95% of the total area AT of the top surface of the micro light-emitting diode packaging structure 500.If the area AD of the distributed Bragg reflector layer is less than 10% of the total area AT of the top surface of the micro light-emitting diode packaging structure 500, the distributed Bragg reflector layer cannot completely reflect the light emitted from the micro light-emitting diode and scattered on the bottom surface to the light-emitting surface, resulting in a poor reflection effect of the micro light-emitting diode packaging structure 500. If the area AD of the distributed Bragg reflector layer is more than 95% of the total area AT of the micro light-emitting diode packaging structure 500, it is difficult to ensure space for the scribe lines and electrical connection parts between the redistribution layer and the external circuit at the edge of the micro light-emitting diode (LED) packaging structure 500.

[0036] 16 is an enlarged cross-sectional view of the micro light-emitting diode (having micro light-emitting diodes 205, 305, and 405) of the micro light-emitting diode package structure 500 according to some embodiments of the present invention, illustrating the outline of the back surfaces 205b, 305b, and 405b of the micro light-emitting diodes 205, 305, and 405, and exemplary structures of the micro light-emitting diodes 205, 305, and 405. As shown in FIG. 16 , in the manufacturing process of the micro light-emitting diode, a laser lift-off (LLO) method is used to separate the growth substrate (e.g., a sapphire substrate) and the semiconductor epitaxial stack structure (having a p-type semiconductor layer, an n-type semiconductor layer, and a light-emitting layer) formed thereon to form a micrometer (μm) scale micro light-emitting diode. As a result, the back surface 205b, 305b, 405b (also regarded as the light-emitting surface) of at least one micro light-emitting diode 205, 305, 405 in the micro light-emitting diode packaging structure 500 is a rough surface, which reduces the loss caused by total internal reflection occurring at the interface between the flexible material layer (shown in Figures 1 to 14) and the back surface 205b, 305b, 405b of the micro light-emitting diode 205, 305, 405, thereby improving the light extraction efficiency of the micro light-emitting diode.

[0037] A method for forming the micro light-emitting diode packaging structure 500 is described below. For ease of explanation, FIGS. 17A-17K to 31A-31C illustrate a method for forming a micro light-emitting diode packaging structure (single pixel unit), but the embodiments of the present invention are not limited thereto. In some other embodiments, the method for forming the micro light-emitting diode packaging structure 500 forms a periodic array of micro light-emitting diode packaging structures.

[0038] 17A-17K are cross-sectional views of different stages in forming the micro light-emitting diode package structure 500a of FIG. 1 according to some embodiments of the present invention. As shown in FIG. 17A, first, a carrier 200 is provided. The carrier 200 is used to carry the micro light-emitting diodes and the controller, so that the micro light-emitting diodes and the controller can be subsequently transferred to a surface 201 of the carrier 200. In some embodiments, the material of the carrier 200 includes glass, sapphire, a transparent polymer, or a combination thereof. Next, an adhesive layer 204 is coated on the surface 201 of the carrier 200. The adhesive layer 204 is used to bond the micro light-emitting diodes and the controller, so that the micro light-emitting diodes and the controller can be subsequently transferred to the surface 201 of the carrier 200. In some embodiments, the adhesive layer 204 includes a polymer material, such as polyimide (PI), epoxy, or silicone, that has adhesive strength and is susceptible to dissociation and destruction at the interface of the carrier 200 during a subsequent removal process (e.g., laser lift-off (LLO)).

[0039] 17B, ​​the control device 212 is placed on the surface 201 of the carrier 200, and the micro light-emitting diode 205 (including the micro light-emitting diodes 206, 208, and 210) is transferred to the surface 201 of the carrier 200. In addition, the control device 212 and the micro light-emitting diode 205 are placed side by side. Furthermore, the back surface 212b of the control device 212 and the back surfaces 206b, 208b, and 210b of the micro light-emitting diodes 206, 208, and 210 are connected to the adhesive layer 204. The contact pads 212p of the control device 212 and the electrodes 206p, 208p, and 210p of the micro light-emitting diodes 206, 208, and 210 are located away from the carrier 200 and the adhesive layer 204. In some embodiments, the control device 212 and the micro light emitting diode 205 are transferred to the carrier 200 by mass transfer techniques, such as stamp transferring and laser transferring.

[0040] 17C, a coating process and a subsequent patterning process are performed to form an insulating layer 216 on the carrier 200. In some embodiments, the insulating layer 216 surrounds and partially covers the controller 212 and the micro light-emitting diodes 206, 208, and 210. In addition, the insulating layer 216 has openings 216a, 216b, 216c, and 216d to expose the contact pads 212p of the controller 212 and the electrodes 206p, 208p, and 210p of the micro light-emitting diodes 206, 208, and 210, respectively.

[0041] Next, as shown in Figure 17D, after the control device 212 and the micro light-emitting diodes 206, 208, 210 are transferred to the carrier 200, a plating process and a subsequent patterning process are performed to form a re-distribution layer 220 on the control device 212 and the micro light-emitting diodes 206, 208, 210. The re-distribution layer 220 passes through the openings 216a, 216b, 216c, 216d (shown in Figure 17C) in the insulating layer 216 and is electrically connected to the contact pads 212p of the control device 212 and the electrodes 206p, 208p, 210p of the micro light-emitting diodes 206, 208, 210, respectively. As shown in Figure 17D, the control device 212 and the micro light-emitting diodes 206, 208, 210 are disposed on a first side 220-1 of the re-distribution layer 220.

[0042] 17E, after the formation of the re-distribution layer 220, a coating process and a subsequent patterning process are performed to form an insulating layer 222 that covers the re-distribution layer 220. The insulating layer 222 has openings 222a that expose a portion of the re-distribution layer 220 to define the locations for the subsequent formation of bonding pads.

[0043] Next, as shown in Figure 17F, a plating step and subsequent patterning process are performed to form bonding pads 224 on the insulating layer 222. The bonding pads 224 pass through openings 222a (shown in Figure 17E) in the insulating layer 222 and are electrically connected to the re-distribution layer 220.

[0044] Next, as shown in Figure 17G, an attachment process is performed using a film application device to attach the thin film layer 226 to the second side 220-2 of the re-distribution layer 220. In some embodiments, the thin film layer 226 does not contact the carrier 200 but contacts the bonding pads 224. In some embodiments, the thin film layer 226 comprises a structure formed by coating an adhesive layer on a substrate, such as a UV tape. The material of the substrate includes epoxy, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyimide (PI), or a combination thereof.

[0045] Next, as shown in Figure 17H, a removal process is performed to remove the carrier 200 from the adhesive layer 204. In some embodiments, the removal process includes laser ablation or other suitable removal process.

[0046] 17I, another removal process is then performed to remove the adhesive layer 204, exposing the back surface 212b of the control device 212 and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210 from the insulating layer 216 to improve the light extraction efficiency of the micro light-emitting diode packaging structure. In some embodiments, the removal process includes chemical etching, plasma etching, or other suitable removal process.

[0047] 17J, after removing the carrier 200 and adhesive layer 204, a film paste process or a coating process is performed to form a flexible material layer 250 covering the controller 212 and the micro light-emitting diodes 206, 208, 210. In some embodiments, the flexible material layer 250 contacts the back surface 212b of the controller 212 and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210.

[0048] Next, as shown in FIG. 17K, a dicing process is performed to cut the flexible material layer 250 and the re-distribution layer 220 along the scribe lines 252L to form a plurality of individual micro light-emitting diode package structures. In some embodiments, the cutting process includes laser cutting, dicing saw cutting, or other suitable dicing process. Finally, the thin film layer 226 is removed to form the micro light-emitting diode package structure 500a shown in FIG.

[0049] In some embodiments, the controller 212 and the micro light-emitting diodes 206, 208, 210 are directly disposed on the flexible material layer to form the micro light-emitting diode packaging structure 500a. Figures 18A-18E are cross-sectional views of different stages in forming the micro light-emitting diode packaging structure 500a shown in Figure 1 according to some embodiments of the present invention, where the reference numerals in the drawings for the same or similar elements as those in Figures 1-16 and 17A-17K represent the same or similar elements.

[0050] 18A, first, a flexible material layer 250 is provided. Next, as shown in FIG. 18B, the control device 212 is placed on the flexible material layer 250, and the micro light-emitting diode 205 (including the micro light-emitting diodes 206, 208, 210) is mass-transferred onto the flexible material layer 250, so that the back surface 212b of the control device 212 and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210 contact the flexible material layer 250. The interfaces 251 between the control device 212 and the micro light-emitting diodes 206, 208, 210 and the flexible material layer 250 are located away from the contact pads 212p of the control device 212 and the electrodes 206p, 208p, 210p of the micro light-emitting diodes 206, 208, 210.

[0051] 18C, a coating process and subsequent patterning process are performed to form an insulating layer 216 on the flexible material layer 250. The insulating layer 216 surrounds the controller 212 and the micro light-emitting diodes 206, 208, 210. Openings 216a, 216b, 216c, 216d in the insulating layer 216 expose the contact pads 212p of the controller 212 and the electrodes 206p, 208p, 210p of the micro light-emitting diodes 206, 208, 210, respectively.

[0052] Next, as shown in Figure 18D, a plating step and subsequent patterning process are performed to form a redistribution layer 220 on the control device 212 and the micro light-emitting diodes 206, 208, 210. The redistribution layer 220 passes through the openings 216a, 216b, 216c, 216d (shown in Figure 18C) in the insulating layer 216 and connects to the contact pads 212p of the control device 212 and the electrodes 206p, 208p, 210p of the micro light-emitting diodes 206, 208, 210, respectively.

[0053] 18E, after the formation of the redistribution layer 220, a coating process and subsequent patterning process are performed to form an insulating layer 222 that covers the redistribution layer 220. The insulating layer 222 has openings 222a that expose a portion of the redistribution layer 220 to define the locations for subsequent formation of bonding pads.

[0054] 1, a plating process and a subsequent patterning process are performed to form bonding pads 224 that penetrate the insulating layer 222 and are electrically connected to the re-distribution layer 220. After performing the above-mentioned processes, the micro light-emitting diode package structure 500a shown in FIG. 1 is formed.

[0055] 19A-19J are cross-sectional views of different stages in forming the micro light-emitting diode package structure 500b of FIG. 2 according to some embodiments of the present invention, in which the symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, and 18A-18E represent the same or similar elements.

[0056] 19A, after performing the process shown in FIG. 17A and FIG. 17B (or the process shown in FIG. 18A), a light-shielding layer 236 is formed on the carrier 200 by spin coating, casting, etc. The light-shielding layer 236 surrounds the control device 212 and the micro light-emitting diodes 206, 208, 210.

[0057] 19B, a process similar to that of FIG. 17C is then performed to form an insulating layer 216 on the light-shielding layer 236. In some embodiments, the insulating layer 216 surrounds the controller 212 and the micro light-emitting diodes 206, 208, 210 and covers the light-shielding layer 236.

[0058] 19C-19G, steps similar to those in Figures 17D-17H are then performed in sequence to form a re-distribution layer 220 on the control device 212 and the micro light-emitting diodes 206, 208, 210. Next, an insulating layer 222 is formed to cover the re-distribution layer 220. Then, bonding pads 224 are formed on the insulating layer 222 and electrically connected to the re-distribution layer 220, after which a thin film layer 226 is attached to the second side 220-2 of the re-distribution layer 220, and then the carrier 200 is removed from the adhesive layer 204.

[0059] Next, as shown in FIG. 19H, a process similar to that of FIG. 17I is performed to remove the adhesive layer 204, thereby exposing the back surface 212b of the control device 212 and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210 from the light-shielding layer 236.

[0060] Next, as shown in FIG. 19I, a process similar to that of FIG. 17J is performed to form a flexible material layer 250 covering the light-shielding layer 236, the back surface 212b of the control device 212, and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210.

[0061] 17K is then performed to cut the light-shielding layer 236, the flexible material layer 250, and the re-distribution layer 220 along the scribe lines 252L to form individual micro light-emitting diode package structures, as shown in FIG. 19J. Finally, the thin film layer 226 is removed to form the micro light-emitting diode package structure 500b shown in FIG. 2. In the micro light-emitting diode package structure 500b, the light-shielding layer 236 is formed before the formation of the insulating layer 216 and the re-distribution layer 220. The light-shielding layer 236 is formed between the re-distribution layer 220 and the flexible material layer 250, and surrounds the controller 212 and the micro light-emitting diodes 206, 208, 210.

[0062] 20A-20I are cross-sectional views of different stages of the micro light-emitting diode package structure 500c of FIG. 3 according to some embodiments of the present invention, in which symbols for elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, and 19A-19J represent the same or similar elements.

[0063] 20A, after performing the process shown in Figure 17A and Figure 17B (the process shown in Figure 18A), a process similar to Figure 19A and a subsequent patterning process are performed to form a light-shielding layer 246 on the carrier 200. The light-shielding layer 246 surrounds and partially covers the control device 212 and the micro light-emitting diodes 206, 208, 210. In addition, the light-shielding layer 246 has openings to expose the contact pads 212p of the control device 212 and the electrodes 206p, 208p, 210p of the micro light-emitting diodes 206, 208, 210, respectively.

[0064] Next, as shown in FIG. 20B, a process similar to that of FIG. 17D is performed to form a redistribution layer 220 on the light-shielding layer 246, the control device 212, and the micro light-emitting diodes 206, 208, 210.

[0065] 20C-20F, processes similar to those in Figures 17E-17H are then performed in sequence to form an insulating layer 222 covering the re-distribution layer 220. Next, bonding pads 224 are formed on the insulating layer 222, and then a thin film layer 226 is attached to the second side 220-2 of the re-distribution layer 220, after which the carrier 200 is removed from the adhesive layer 204.

[0066] Next, as shown in FIG. 20G, a process similar to that of FIG. 17I is performed to remove the adhesive layer 204, thereby exposing the back surface 212b of the control device 212 and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210 from the light-shielding layer 246.

[0067] Next, as shown in FIG. 20H, a process similar to that of FIG. 17J is performed to form a flexible material layer 250 covering the light-shielding layer 246, the back surface 212b of the control device 212, and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210.

[0068] 20I, a process similar to that of FIG. 17K is then performed to cut the flexible material layer 250 and the re-distribution layer 220 along the scribe lines 252L to form individual micro light-emitting diode package structures. Finally, the thin film layer 226 is removed to form the micro light-emitting diode package structure 500c shown in FIG. 3. In the micro light-emitting diode package structure 500c, a light-shielding layer 246 is formed before the formation of the re-distribution layer 220. The light-shielding layer 246 is formed between the re-distribution layer 220 and the flexible material layer 250 and surrounds the controller 212 and the micro light-emitting diodes 206, 208, 210.

[0069] 21A-21I are cross-sectional views of different stages in forming the micro light-emitting diode package structure 500d of FIG. 4 according to some embodiments of the present invention, in which the symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, 19A-19J, and 20A-20I represent the same or similar elements.

[0070] 21A, after performing the process shown in Figures 17A and 17B (or the process shown in Figure 18A), a deposition process and a subsequent patterning process are performed to form a distributed Bragg reflector layer 240 on the micro light-emitting diodes 206, 208, 210. The distributed Bragg reflector layer 240 extends from the sidewalls of the micro light-emitting diodes 206, 208, 210 and is adjacent to the electrodes 206p, 208p, 210p. In addition, the distributed Bragg reflector layer 240 has openings 240a, 240b, and 240c to expose the contact pads 212p of the control device 212 and the electrodes 206p, 208p, 210p of the micro light-emitting diodes 206, 208, 210, respectively.

[0071] 21B, the processes shown in Figure 17C and Figure 17D are carried out in order to form an insulating layer 216 on the carrier 200 and the distributed Bragg reflector layer 240, and surround the distributed Bragg reflector layer 240, the control device 212, and the micro light-emitting diodes 206, 208, 210. In addition, a re-distribution layer 220 is formed on the insulating layer 216, the distributed Bragg reflector layer 240, the control device 212, and the micro light-emitting diodes 206, 208, 210, and the re-distribution layer 220 contacts the distributed Bragg reflector layer 240.

[0072] Next, as shown in Figures 21C to 21G, processes similar to those in Figures 17E to 17I are performed in sequence to form an insulating layer 222 and a bonding pad 224 on the redistribution layer 220, and then a thin film layer 226 is attached to the second side 220-2 of the redistribution layer 220, and then the carrier 200 is removed from the adhesive layer 204, and then the adhesive layer 204 is removed, thereby exposing the back surface 212b of the control device 212 and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210 from the insulating layer 216 and the distributed Bragg reflector layer 240.

[0073] Next, as shown in FIG. 21H, a process similar to that of FIG. 17J is performed to form a flexible material layer 250 covering the distributed Bragg reflector layer 240, the back surface 212b of the control device 212, and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210.

[0074] 17K is then performed to cut the flexible material layer 250 and the re-distribution layer 220 along the scribe lines 252L to form a plurality of individual micro light-emitting diode package structures, as shown in FIG. 21I. Finally, the thin film layer 226 is removed to form the micro light-emitting diode package structure 500d shown in FIG. 4. In the micro light-emitting diode package structure 500d, the distributed Bragg reflector layer 240 is formed before the formation of the re-distribution layer 220. The distributed Bragg reflector layer 240 is formed between the re-distribution layer 220 and the flexible material layer 250 and surrounds the controller 212 and the micro light-emitting diodes 206, 208, 210.

[0075] 22A-22I are cross-sectional views of different stages of the micro light-emitting diode package structure 500e of FIG. 5 according to some embodiments of the present invention, in which symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, 19A-19J, 20A-20I, and 21A-21I represent the same or similar elements.

[0076] 22A, after the processes shown in Figure 17A and Figure 17B (or the process shown in Figure 18A) are performed in order, the process shown in Figure 21A is performed to form a distributed Bragg reflector layer 240 on the micro light-emitting diodes 206, 208, 210. Next, the process shown in Figure 19A is performed to form a light-shielding layer 236 on the carrier 200 and surround the distributed Bragg reflector layer 240, the control device 212, and the micro light-emitting diodes 206, 208, 210.

[0077] 22B to 22G, processes similar to those in FIGS. 17C to 17I are sequentially performed to form an insulating layer 216 on the light-shielding layer 236 and the distributed Bragg reflector layer 240. Next, a re-distribution layer 220 is formed on the insulating layer 216. Next, an insulating layer 222 and a bonding pad 224 are sequentially formed on the re-distribution layer 220. Next, a thin film layer 226 is attached to the second side 220-2 of the re-distribution layer 220. Next, the carrier 200 is removed from the adhesive layer 204. After that, the adhesive layer 204 is removed, so that the back surface 212b of the control device 212 and the back surfaces 206b, 208b, and 210b of the micro light-emitting diodes 206, 208, and 210 are exposed from the light-shielding layer 236 and the distributed Bragg reflector layer 240.

[0078] Next, as shown in FIG. 22H, a process similar to that of FIG. 17J is performed to form a flexible material layer 250 covering the light-shielding layer 236, the distributed Bragg reflector layer 240, and the back surface 212b of the control device 212 and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210.

[0079] 22I, a process similar to that of FIG. 17K is then performed to cut the light-shielding layer 236, the flexible material layer 250, and the re-distribution layer 220 along the scribe lines 252L to form individual micro light-emitting diode package structures. Finally, the thin film layer 226 is removed to form the micro light-emitting diode package structure 500e shown in FIG. 5. In the micro light-emitting diode package structure 500e, the light-shielding layer 236 and the distributed Bragg reflector layer 240 are formed before forming the re-distribution layer 220. The light-shielding layer 236 and the distributed Bragg reflector layer 240 are formed between the re-distribution layer 220 and the flexible material layer 250, and surround the controller 212 and the micro light-emitting diodes 206, 208, 210.

[0080] 23A-23H are cross-sectional views of different stages in forming the micro light-emitting diode package structure 500f of FIG. 6 according to some embodiments of the present invention, in which the symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, 19A-19J, 20A-20I, 21A-21I, and 22A-22I represent the same or similar elements.

[0081] As shown in Figure 23A, the processes shown in Figure 17A and Figure 17B (or the process shown in Figure 18A) are performed in order. Next, the process shown in Figure 21A is performed, and then the process shown in Figure 20A is performed to form a light-shielding layer 246 on the carrier 200. The light-shielding layer 246 surrounds the distributed Bragg reflector layer 240, the control device 212, and the micro light-emitting diodes 206, 208, 210. Next, a process similar to Figure 17D is performed to form a re-distribution layer 220 on the light-shielding layer 246, the distributed Bragg reflector layer 240, the control device 212, and the micro light-emitting diodes 206, 208, 210.

[0082] 23B to 23F, processes similar to those in Figures 17E to 17I are then performed in order to form an insulating layer 222 and a bonding pad 224 on the re-distribution layer 220, and then a thin film layer 226 is attached to the second side 220-2 of the re-distribution layer 220, and then the carrier 200 is removed from the adhesive layer 204. Next, the adhesive layer 204 is removed, thereby exposing the back surface 212b of the control device 212 and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210 from the light-shielding layer 246 and the distributed Bragg reflector layer 240.

[0083] Next, as shown in FIG. 23G, a process similar to that of FIG. 17J is performed to form a flexible material layer 250 covering the light-shielding layer 246, the distributed Bragg reflector layer 240, the back surface 212b of the control device 212, and the back surfaces 206b, 208b, 210b of the micro light-emitting diodes 206, 208, 210.

[0084] 17K is then performed to cut the light-shielding layer 246, the flexible material layer 250, and the re-distribution layer 220 along the scribe lines 252L to form individual micro light-emitting diode package structures, as shown in FIG. 23H. Finally, the thin film layer 226 is removed to form the micro light-emitting diode package structure 500f shown in FIG. 6. In the micro light-emitting diode package structure 500f, the light-shielding layer 246 and the distributed Bragg reflector layer 240 are formed before the formation of the re-distribution layer 220. The light-shielding layer 246 and the distributed Bragg reflector layer 240 are formed between the re-distribution layer 220 and the flexible material layer 250, and surround the controller 212 and the micro light-emitting diodes 206, 208, 210.

[0085] 24A-24H are cross-sectional views of different stages in forming the micro light-emitting diode package structure 500g of FIG. 7 according to some embodiments of the present invention, in which the symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, 19A-19J, 20A-20I, 21A-21I, 22A-22I, and 23A-23H represent the same or similar elements.

[0086] 24A, first, carrier 300 is provided. In some embodiments, carrier 200 and carrier 300 have the same or similar materials. Next, adhesive layer 304 is coated on surface 301 of carrier 300. In some embodiments, adhesive layers 204 and 304 have the same or similar materials.

[0087] Next, as shown in Figure 24B, the control device 312 is placed on the carrier by mass transfer techniques, such as stamp transferring and laser transferring. Next, a removal process is performed to remove the adhesive layer 304 that is not covered by the control device 312. The remaining adhesive layer between the back surface 312b of the control device 312 and the carrier 300 is shown as adhesive layer 304R. In some embodiments, the removal process includes chemical etching, plasma etching, or other suitable removal processes.

[0088] Next, as shown in Figure 24C, after placing the control device 312 on the carrier 300, a coating process and a subsequent patterning process are performed to form an insulating layer 316 that covers the carrier 300 and the control device 312. The insulating layer 316 conformally covers and surrounds the control device 312. In addition, the insulating layer 316 has openings 316a that expose the contact pads 312p of the control device 312.

[0089] Next, as shown in Figure 24D, after the control device 312 is placed on the carrier 300, a plating process and a subsequent patterning process are performed to form a re-distribution layer 320 on the control device 312. The re-distribution layer 320 partially covers the insulating layer 316 and passes through the openings 316a (Figure 24C) to electrically connect with the contact pads 312p of the control device 312. As shown in Figure 24D, the control device 312 is placed on a first side 320-1 of the re-distribution layer 320.

[0090] Next, as shown in FIG. 24E, after the redistribution layer 320 is formed, the micro light-emitting diodes 305 (including micro light-emitting diodes 306, 308, and 310) are transferred to the surface 301 of the carrier 300. The controller 312 and the micro light-emitting diodes 305 are disposed side by side. In addition, the micro light-emitting diodes 305 are disposed on the second side 320-2 of the redistribution layer 320. As shown in FIG. 24E, the electrodes 306p, 308p, and 310p of the micro light-emitting diodes 306, 308, and 310 are electrically connected to the redistribution layer 320. In addition, the contact pads 312p of the controller 312 and the back surfaces 306b, 308b, and 310b of the micro light-emitting diodes 306, 308, and 310 are located away from the carrier 300. In some embodiments, the micro light-emitting diodes 205 and 305 have the same or similar arrangements and transfer methods.

[0091] Next, as shown in Figure 24F, a film paste or coating process is performed to form a flexible material layer 350 that covers the controller 312 and the micro light emitting diodes 306, 308, 310. In some embodiments, the flexible material layer 350 contacts the back surfaces 306b, 308b, 310b of the micro light emitting diodes 306, 308, 310 and is separated from the controller 312 by the insulating layer 316 and the redistribution layer 320.

[0092] Next, as shown in FIG. 24G, a thin film layer 326 is attached to the second side 320-2 of the re-distribution layer 320 by performing an attachment process using a film application device. In some embodiments, the thin film layer 326 does not contact the carrier 300 but contacts the flexible material layer 350. In some embodiments, the thin film layers 226 and 326 comprise the same or similar materials. Next, a removal process is performed to remove the carrier 300 from the adhesive layer 304R. In some embodiments, the removal process comprises laser peeling or other suitable removal processes.

[0093] Next, as shown in FIG. 24H, a patterning process is performed on the insulating layer 316 to form openings 316b and 316c in the insulating layer 316 that expose portions of the re-distribution layer 320 so that the re-distribution layer 320 can be electrically connected to an external circuit. A dicing process is then performed to cut the flexible material layer 350 and the re-distribution layer 320 along scribe lines 352L to form a plurality of individual micro light-emitting diode package structures. In some embodiments, the dicing process includes laser cutting, dicing saw cutting, or other suitable dicing process. Finally, as shown in FIG. 7, the thin film layer 326 is removed to form the micro light-emitting diode package structure 500g. Compared with the micro LED packaging structures 500a-500f, the method for forming the micro LED packaging structure 500g includes forming a re-distribution layer 320 after placing the control device 312 on the carrier 300, and after forming the re-distribution layer 320, the micro LEDs 305 are transferred to the carrier 300. Before forming the re-distribution layer 320, an insulating layer 316 is formed to cover the carrier 300 and the control device 312. In addition, before removing the carrier 300, a flexible material layer 350 is formed.

[0094] 25A-25D are cross-sectional views of different stages in forming the micro light-emitting diode package structure 500h of FIG. 8 according to some embodiments of the present invention, in which the symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, 19A-19J, 20A-20I, 21A-21I, 22A-22I, 23A-23H, and 24A-24H represent the same or similar elements.

[0095] As shown in FIG. 25A, after sequentially performing processes similar to those in FIGS. 24A-24E, a coating process is performed to conformally cover the redistribution layer 320 and form a light-shielding layer 336 surrounding the micro light-emitting diodes 306, 308, and 310.

[0096] Next, as shown in FIGS. 25B-25D, processes similar to those in FIGS. 24F-24H are performed in sequence to form a flexible material layer 350 covering the light-shielding layer 336, the control device 312, and the micro light-emitting diodes 306, 308, and 310. Next, a thin film layer 326 is attached to the second side 320-2 of the re-distribution layer 320. Next, the carrier 300 is removed from the adhesive layer 304R. Next, the flexible material layer 350 and the re-distribution layer 320 are cut along scribe lines 352L to form a plurality of individual micro light-emitting diode package structures. Finally, the thin film layer 326 is removed to form the micro light-emitting diode package structure 500h shown in FIG. 8. Compared to the micro light-emitting diode package structure 500g, the micro light-emitting diode package structure 500h has the light-shielding layer 336 formed after the re-distribution layer 320 is formed and the micro light-emitting diodes 305 are mass-transferred to the carrier 300. A light blocking layer 336 is formed between the redistribution layer 320 and the flexible material layer 350 and surrounds the micro light emitting diodes 305 .

[0097] 26A-26G are cross-sectional views of different stages in forming the micro light-emitting diode package structure 500i of FIG. 9 according to some embodiments of the present invention, in which the symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, 19A-19J, 20A-20I, 21A-21I, 22A-22I, 23A-23H, 24A-24H, and 25A-25D represent the same or similar elements.

[0098] 24A-24C, a plating step is performed to form bonding pads 324 on the insulating layer 316. The bonding pads 324 are used to connect the redistribution layer 320, which is subsequently formed thereon, to external circuitry.

[0099] 26B, a deposition process and a subsequent patterning process are performed to form a distributed Bragg reflector layer 340 on the insulating layer 316. In addition, the distributed Bragg reflector layer 340 has openings 340a, 340b, and 340c to expose the contact pads 312p and the bonding pads 324 of the control device 312, respectively.

[0100] Next, as shown in Figures 26C-26G, processes similar to those in Figures 24D-24H are performed in sequence to form a re-distribution layer 320 on the distributed Bragg reflector layer 340 and the control device 312. Next, the micro light-emitting diodes 305 are transferred to the carrier 300, and a flexible material layer 350 is formed covering the distributed Bragg reflector layer 340, the control device 312, and the micro light-emitting diodes 306, 308, and 310. Next, a thin film layer 326 is attached to the second side 320-2 of the re-distribution layer 320. Thereafter, the adhesive layer 304R is removed from the carrier 300, and the flexible material layer 350 and the re-distribution layer 320 are cut along the scribe lines 352L to form a plurality of individual micro light-emitting diode package structures. Finally, the thin film layer 326 is removed to form the micro light-emitting diode package structure 500i shown in Figure 9. Compared with the micro light-emitting diode packaging structure 500g, the micro light-emitting diode packaging structure 500i has a distributed Bragg reflector layer 340 formed adjacent to the electrodes 306p, 308p, and 310p of the micro light-emitting diodes 306, 308, and 310 before the formation of the re-distribution layer 320. In addition, the re-distribution layer 320 contacts the distributed Bragg reflector layer 340.

[0101] 27A-27D are cross-sectional views of different stages in forming the micro light-emitting diode package structure of FIG. 10 according to some embodiments of the present invention, in which the symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, 19A-19J, 20A-20I, 21A-21I, 22A-22I, 23A-23H, 24A-24H, 25A-25D, and 26A-26G represent the same or similar elements.

[0102] As shown in FIG. 27A, processes similar to those in FIGS. 24A-24C and 26A-26D are performed in sequence, and then a process similar to that in FIG. 25A is performed to conformally cover the redistribution layer 320 and the distributed Bragg reflector layer 340 and form a light-shielding layer 336 surrounding the micro light-emitting diodes 306, 308, and 310.

[0103] Next, as shown in Figures 27B-27D, processes similar to those in Figures 24F-24H are performed in sequence to form a flexible material layer 350 covering the light-shielding layer 336, the distributed Bragg reflector layer 340, the controller 312, and the micro light-emitting diodes 306, 308, and 310. Next, a thin film layer 326 is attached to the second side 320-2 of the re-distribution layer 320. Next, the carrier 300 is removed from the adhesive layer 304R. Next, the light-shielding layer 336, the distributed Bragg reflector layer 340, the flexible material layer 350, and the re-distribution layer 320 are cut along scribe lines 352L to form a plurality of individual micro light-emitting diode package structures. Finally, the thin film layer 326 is removed to form the micro light-emitting diode package structure 500k shown in Figure 10. Compared with the micro LED packaging structure 500g, the micro LED packaging structure 500k has a distributed Bragg reflector layer 340 formed before the formation of the redistribution layer 320. In addition, after the redistribution layer 320 is formed and the micro LEDs 305 are mass-transferred to the carrier 300, a light-shielding layer 336 is formed.

[0104] 28A-28F are cross-sectional views of different stages in forming the micro light-emitting diode package structure of FIG. 11 according to some embodiments of the present invention, in which the symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, 19A-19J, 20A-20I, 21A-21I, 22A-22I, 23A-23H, 24A-24H, 25A-25D, 26A-26G, and 27A-27D represent the same or similar elements.

[0105] 28A, first, carrier 400 is provided. In some embodiments, carriers 200, 300, and 400 have the same or similar materials. Next, adhesive layer 404 is coated on surface 401 of carrier 400. In some embodiments, adhesive layers 204, 304, and 404 have the same or similar materials. In some embodiments, carrier 400 is not coated with adhesive layer 404.

[0106] 28B, a coating process and a subsequent patterning process are performed to form an insulating layer 416 covering the surface 401 of the carrier 400. The insulating layer 416 serves as a support layer for the control device 412 and has openings 416a, 416b to define connection portions for the re-distribution layer 420 to be formed thereon later. After the formation of the insulating layer 416, the control device 412 is placed on the insulating layer 416. In some embodiments, the back surface 412b of the control device 412 contacts the insulating layer 416.

[0107] Next, as shown in Figure 28C, after the control device 412 is placed on the carrier 400, a plating process and a subsequent patterning process are performed to form a re-distribution layer 420 on the control device 412. The re-distribution layer 420 partially covers the insulating layer 416 and passes through openings 416a and 416b (shown in Figure 28B) in the insulating layer 416 to be electrically connected to the control device 412. As shown in Figure 28C, the control device 412 is placed on a first side 420-1 of the re-distribution layer 420.

[0108] Next, as shown in FIG. 28D, after forming the redistribution layer 420, the micro light-emitting diodes 405 (including the micro light-emitting diodes 406, 408, and 410) are mass-transferred directly above the control device 412. In addition, the micro light-emitting diodes 405 are disposed on the second side 420-2 of the redistribution layer 420. As shown in FIG. 28D, the electrodes 406p, 408p, 410p of the micro light-emitting diodes 406, 408, 410 are electrically connected to the redistribution layer 420. In addition, the back surfaces 406b, 408b, 410b of the micro light-emitting diodes 406, 408, 410 are located away from the carrier 400. In some embodiments, the micro light-emitting diodes 205, 305, 405 have the same or similar arrangements and transfer methods.

[0109] 28E, a film paste or coating process is then performed to form a flexible material layer 450 that covers the controller 412 and the micro light emitting diodes 406, 408, and 410. In some embodiments, the flexible material layer 450 contacts the back surfaces 406b, 408b, 410b of the micro light emitting diodes 406, 408, and 410 and is separated from the controller 412 by the redistribution layer 420.

[0110] Next, as shown in FIG. 28F, a removal process is performed to remove the carrier 400 from the adhesive layer 404. In some embodiments, the removal process includes laser peeling or other suitable removal processes. Next, a dicing process is performed to cut the flexible material layer 450 and the re-distribution layer 420 along the scribe lines 452L to form a plurality of individual micro light-emitting diode package structures. In some embodiments, the dicing process includes laser cutting, dicing saw cutting, or other suitable dicing processes. Finally, the micro light-emitting diode package structure 500l shown in FIG. 11 is formed. Compared to the micro light-emitting diode package structures 500a-500i and 500k, the method of forming the micro light-emitting diode package structure 500l includes forming the re-distribution layer 420 after placing the control device 412 on the carrier 400. In addition, after forming the re-distribution layer 420, the micro light-emitting diodes 405 are transferred directly above the control device 412. Furthermore, an insulating layer 416 is formed to cover the carrier 400 before the installation of the control device 412. Furthermore, a flexible material layer 450 is formed before the removal of the carrier 400.

[0111] 29A-29E are cross-sectional views of different stages in forming the micro light-emitting diode package structure 500m of FIG. 12 according to some embodiments of the present invention, in which the symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, 19A-19J, 20A-20I, 21A-21I, 22A-22I, 23A-23H, 24A-24H, 25A-25D, 26A-26G, and 27A-27D, and 28A-28F represent the same or similar elements.

[0112] 28A and 28B, a deposition process and a subsequent patterning process are performed to form a distributed Bragg reflector layer 440 on the insulating layer 416. In addition, the distributed Bragg reflector layer 440 has openings 416a and 416b, as well as openings corresponding to the positions of the electrodes of the micro light-emitting diodes 405 to be subsequently transferred thereon, so that the subsequently formed redistribution layer 420 can pass through the openings to electrically connect the control device 412 and the micro light-emitting diodes 405 to an external circuit.

[0113] 29B-29E, processes similar to those in FIGS. 28C-28F are then performed in sequence to form the re-distribution layer 420 on the distributed Bragg reflector layer 440 and the control device 412. Next, the micro light-emitting diode 405 (having the micro light-emitting diodes 406, 408, and 410) is mass-transferred directly on top of the control device 412. Next, a flexible material layer 450 is formed to cover the distributed Bragg reflector layer 440, the control device 412, and the micro light-emitting diodes 406, 408, and 410. Next, the carrier 400 is removed to form the adhesive layer 404. Next, the distributed Bragg reflector layer 440, the flexible material layer 450, and the re-distribution layer 420 are cut along the scribe lines 452L. Finally, the micro light-emitting diode package structure 500m shown in FIG. 12 is formed. Compared with the micro light-emitting diode packaging structure 500l, the micro light-emitting diode packaging structure 500m has a distributed Bragg reflector layer 440 formed adjacent to the electrodes 406p, 408p, and 410p of the micro light-emitting diodes 406, 408, and 410 before the formation of the redistribution layer 420. In addition, the redistribution layer 420 contacts the distributed Bragg reflector layer 440.

[0114] 30A-30C are cross-sectional views of different stages in forming the micro light-emitting diode package structure 500n of FIG. 3 according to some embodiments of the present invention, in which the symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, 19A-19J, 20A-20I, 21A-21I, 22A-22I, 23A-23H, 24A-24H, 25A-25D, 26A-26G, 27A-27D, 28A-28F, and 29A-29E represent the same or similar elements.

[0115] As shown in FIG. 30A, after sequentially performing processes similar to those in FIGS. 28A-28D, a coating process is performed to conformally cover the redistribution layer 420 and the control device 412 and form a light-shielding layer 436 surrounding the micro light-emitting diodes 406, 408, and 410.

[0116] 28E and 28F are then sequentially performed to form a flexible material layer 450 covering the light-shielding layer 436, the control device 412, and the micro light-emitting diodes 406, 408, and 410, as shown in Figures 30B and 30C. Next, the carrier 400 is removed from the adhesive layer 404. Next, the light-shielding layer 436, the flexible material layer 450, and the re-distribution layer 420 are cut along the scribe lines 452L. Finally, the micro light-emitting diode package structure 500n shown in Figure 13 is formed. Compared with the micro light-emitting diode package structure 500l, in the micro light-emitting diode package structure 500n, the light-shielding layer is formed after the re-distribution layer 420 is formed and after the micro light-emitting diodes 405 are mass-transferred onto the carrier 400.

[0117] 31A-31C are cross-sectional views of different stages in forming the micro light-emitting diode package structure of FIG. 14 according to some embodiments of the present invention, in which the symbols of elements that are the same or similar to those in FIGS. 1-16, 17A-17K, 18A-18E, 19A-19J, 20A-20I, 21A-21I, 22A-22I, 23A-23H, 24A-24H, 25A-25D, 26A-26G, 27A-27D, 28A-28F, 29A-29E, and 30A-30C represent the same or similar elements.

[0118] As shown in FIG. 31A, after sequentially performing processes similar to those in FIG. 28A, FIG. 28B, and FIG. 29A-FIG. 29C, a process similar to that in FIG. 30A is performed to conformally form a light-shielding layer 436 that covers the distributed Bragg reflector layer 440, the redistribution layer 420, and the control device 412, and surrounds the micro light-emitting diodes 406, 408, and 410.

[0119] 28E and 28E are sequentially performed to form a flexible material layer 450 covering the light-shielding layer 436, the distributed Bragg reflector layer 440, the control device 412, and the micro light-emitting diodes 406, 408, and 410. Next, the carrier 400 is removed from the adhesive layer 404, and then the light-shielding layer 436, the distributed Bragg reflector layer 440, the flexible material layer 450, and the re-distribution layer 420 are cut along the scribe lines 452L. Finally, the micro light-emitting diode package structure 500p shown in FIG. 14 is formed. Compared with the micro LED packaging structure 500l, the micro LED packaging structure 500p forms a distributed Bragg reflector layer 440 adjacent to the electrodes 406p, 408p, 410p of the micro LEDs 406, 408, and 410 before the redistribution layer 420 is formed. In addition, after the redistribution layer 420 is formed and the micro LEDs 405 are mass-transferred to the carrier 400, the light-shielding layer 436 is formed.

[0120] Micro light-emitting diode packaging structures and methods for forming the same according to some embodiments of the present invention integrate a controller and a micro light-emitting diode in the same packaging structure to form individually / independently controlled pixel packages. The micro light-emitting diode packaging structure includes a redistribution layer, a controller, a micro light-emitting diode, and a flexible material layer. The controller and the micro light-emitting diode are disposed on and electrically connected to the redistribution layer. The flexible material layer covers the controller and the micro light-emitting diode, and the micro light-emitting diode is in contact with the flexible material layer. In some embodiments, the micro light-emitting diode packaging structure further includes a distributed Bragg reflector layer adjacent to the electrodes of the micro light-emitting diode and in contact with the redistribution layer to increase the light-emitting efficiency of the micro light-emitting diode packaging structure. In some embodiments, the micro light-emitting diode packaging structure further includes a light-shielding layer disposed between the redistribution layer and the flexible material layer to improve the contrast of the micro light-emitting diode packaging structure. In some embodiments, the controller and the micro light-emitting diode are disposed on the same side or on opposite sides of the redistribution layer. Alternatively, the micro light-emitting diode may be placed directly above a control device, such as a thin film transistor device, to further reduce the size of the micro light-emitting diode packaging structure. The micro light-emitting diode packaging structure according to some embodiments of the present invention further reduces the volume of the packaging structure and is applied to small-pitch displays, such as wearable display devices or special totem micro light sources.

[0121] Although preferred embodiments of the present invention have been disclosed as described above, these are by no means intended to limit the scope of the present invention, and anyone familiar with the art can make various modifications within the scope of the present invention. [Explanation of symbols]

[0122] 200,300,400 Carrier, 201,301,401 Surface, 204,304,304R,404 Adhesive layer, 205,206,208,210,305,306,308,310,405,406,408,410 Micro light-emitting diode, 205b,206b,208b,210b,212b,305b,306b,308b,310b,405b,406b,408b,410b,412b Back, 206p,208p,210p,306p,308p,310p,406p,408p,410p Electrode, 212,312,412 Control device, 212p,312p Contact pad, 216,222,316 Insulating layer, 216a,216b,216c,216d,222a,240a,240b,240c,316a,316b,316c,340a,340b,340c,416a,416b Opening, 220,320,420 Redistribution layer, 220-1,320-1,420-1 First side, 220-2,320-2,420-2 Second side, 224,324 Bonding pad, 226,326 Thin film layer, 236,246,336,436 Light shielding layer, 240,340,440 distributed Bragg reflective layer, 250,350,450 flexible material layer, 251 Interface, 252L, 352L, 452L Scribe line, 260, 360, 460 Emitting surface, 500a, 500b, 500c, 500d, 500e, 500f, 500g, 500h, 500i, 500k, 500l, 500m, 500n, 500p Micro LED structure, AD Area, AT Total area.

Claims

1. A micro light emitting diode package structure, comprising: a redistribution layer having a first side and a second side opposite the first side; a control device disposed on the redistribution layer and electrically connected to the redistribution layer; a plurality of micro light emitting diodes disposed on the redistribution layer and electrically connected to the redistribution layer; a flexible material layer covering the control device and the micro light-emitting diodes and in contact with the micro light-emitting diodes; the control device is disposed on the first side of the redistribution layer; a plurality of the micro light emitting diodes are disposed on the second side of the redistribution layer; The control device and the micro light-emitting diode are arranged side by side in a horizontal direction; At least one of the back surfaces of the micro light emitting diodes is a rough surface; moreover, the redistribution layer has an outwardly extending portion; The outwardly extending portion provides electrical connections between the anodes and common cathode of the plurality of micro light-emitting diodes and an external circuit.

1. A micro light emitting diode package structure comprising:

2. The plurality of micro light emitting diodes have a plurality of sidewalls and a plurality of electrodes; The flexible material layer is in contact with the side walls and the electrodes. The micro light-emitting diode package structure according to claim 1 .

3. a first insulating layer in contact with the control device and disposed on the first side of the redistribution layer; The micro light-emitting diode package structure according to claim 1 .

4. a distributed Bragg reflector layer in contact with the first side of the redistribution layer and conformally covering the first insulating layer; a plurality of bonding pads disposed between the first insulating layer and the distributed Bragg reflector layer and electrically connected to the redistribution layer; The area of ​​the distributed Bragg reflector layer is 10% or more and 95% or less of the total area of ​​the top surface of the micro light emitting diode packaging structure. The micro light-emitting diode package structure according to claim 3 .

5. a light-shielding layer provided on the second side of the re-distribution layer and conformally covering the re-distribution layer; The micro light-emitting diode package structure according to claim 3 .

6. The flexible material layer is in contact with the light-shielding layer.

6. The micro light-emitting diode package structure according to claim 5.

7. the control device has a back surface and a contact pad; The back surface is remote from the contact pads and exposed from the first insulating layer. The micro light-emitting diode package structure according to claim 3 .

8. having a light-emitting surface, The plurality of micro light-emitting diodes are closer to the light-emitting surface than the control device. The micro light-emitting diode package structure according to claim 1 .

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