Micro-LED Display Efficient Fabrication Methods

Micro LED display with transferable micro LEDs that have improved structural stability during transfer and reduced risk of damage. The micro LED structure has a support structure with a protrusion that contacts the support structure itself. This provides localized support to prevent bending and breaking during transfer. The support structure also has a suspended portion that avoids contact with the substrate during imprinting. The thickness and width of the protrusion and bridge arms are optimized for strength and stress regulation.

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Efficiently transferring arrays of micro LEDs using a stamping technique to improve the speed and yield of transferring large numbers of micro LEDs compared to pick-and-place methods. The method involves: 1. Preparing a source wafer with micro LEDs and a temporary carrier substrate with a stamping array. 2. Aligning the source wafer with the temporary carrier substrate. 3. Pressing the stamping array onto the source wafer to transfer the micro LEDs onto the temporary carrier substrate. 4. Removing the source wafer and preparing the temporary carrier substrate as the new source for the next transfer cycle. This allows transferring multiple micro LEDs at once using a stamping array instead of pick-and-place transfer of individual micro LEDs.

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Full-color micro-LED (µLED) display without electrical contact. It achieves a full-color display using a blue µLED grain emitting light through a down-conversion layer. The display uses upper and lower driving electrodes that do not directly interact with the µLED grain. A driving electric field recombines electrons and holes in the µLED to emit blue light. A down-conversion layer converts the blue light to yellow, which mixes with the blue light. The mixed light passes through a reflector and diffuser to form uniform white light. Color filters then convert the white light to red, green, and blue for full-color display.

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Micro LED display device that can meet the requirements of high resolution and has a high manufacturing yield. The device has a circuit substrate with micro LED units on one side and a metal conductive layer on the other side. The conductive layer contacts the epitaxial layer of the micro LEDs and has light conversion regions. A light conversion layer in some regions converts emitted light. Light-shielding structures on the epitaxial layer cover some areas. The metal layer is thicker than the epitaxial layer.

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Display device using microLED technology with improved luminous efficiency and production yield compared to conventional microLED displays. The device has microLED elements directly manufactured on the display circuit substrate. An insulating layer covers the lower sidewalls of the microLEDs. A common electrode layer covers the insulating layer and exposed top surfaces of the microLEDs. The common electrode layer contacts the upper sidewalls of the microLEDs. This configuration allows electrical connection to the microLEDs while leaving the top surface exposed for light emission. It provides efficient, compact, and direct microLED integration on the display substrate without transfer processes.

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Micro light-emitting diode display panel that can be used for high reliability, high yield, high scalability, high selectivity and high success rate. The panel includes a backplane having a plurality of bonding structures, and a plurality of light-emitting diode dies disposed on the backplane and bonded with at least some bonding structures in the backplane.

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Method for manufacturing displays using self-assembly of micro LEDs to increase yield and enable large-scale production. The method involves transferring micro LEDs grown on a source substrate to a temporary board with sacrificial layer. Then, cells on an acceptor board are filled with fluid and aligned with the temporary board. An electric field is applied to move the micro LEDs from the temporary to the acceptor board while maintaining interval. This allows precise placement of micro LEDs in cells without alignment errors. The temporary board is removed and the micro LEDs are fixed in place on the acceptor board. This enables high-yield transfer of micro LEDs from the growth substrate to the display board using self-assembly.

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Manufacturing a micro LED display substrate that can be used for digital cameras and other mobile devices. The substrate includes forming an array of micro LEDs on an epitaxial wafer, transferring the array of micro LEDs on the epitaxial wafer to an adhesive layer on a surface of a transfer substrate assembly, and transferring the array of micro LEDs on the surface of the transfer substrate assembly onto corresponding pads on a driving substrate respectively.

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Micro-LED display structure with high-yield manufacturing. The LED structure includes an LED driving circuit with conductive pads that contact some LED units. This allows selective bonding of LED units to the circuit through the conductive pads. The remaining LED units without pads are dummy units. This prevents the need for precise alignment of every LED unit during bonding. It enables high-yield micro-LED fabrication of high-resolution displays with micro/nano-sized LEDs.

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Full color LED structure and manufacturing method for micro-LED displays that allows integrating multiple sub-pixels with different colors to form a full color pixel. The structure includes multiple LED units stacked vertically. First and second LED units emit light of a first color, while a third LED unit emits light of a second color. A color conversion layer on the first LED unit converts its light to a third color. The LED units are electrically isolated to drive them separately. The LED units are formed on a substrate and the isolation is done by implanting material between the doped layers. This allows integrating multi-color micro-LEDs for high resolution displays without the need for mass-transfer.

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Micro LED display panel that can be formed on a substrate without the need of semiconductor fabrication. The panel includes a first substrate with a first plurality of light emitting diode chips, a paired Ohmic electrodes being formed on each of the first light emitting diode chips, wherein the each light emitting diode emits light with a first wavelength, providing a second substrate with driving circuits thereon for the display panel and a plurality of paired bonding pads, flipping the first substrate to bond the first plurality of light emitting diode chips on the plurality of the paired bonding pads, separating the first plurality of light emitting diode chips from the first substrate, and reheating the second substrate such that the first plurality of light emitting diode chips are fastened on the second substrate.

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Micro LED display device that allows efficient color conversion from blue emitting micro LEDs to full color output using a simple structure. A blue micro LED array is covered with a yellow phosphor layer that converts blue light to yellow light. The phosphor layer has holes that align with color filter areas for green and red. Blue light passes through the phosphor holes and color filters to emit as green and red, creating a full color display without transferring individual red and green LEDs.

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Manufacturing a micro-LED device that can be used for being mounted on a display screen. The device includes a micro-LED array for display, a method for transferring micro-LED, a method for manufacturing a micro-LED device, a micro-LED device and an electronic apparatus containing a micro-LED device.

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Fabricating flexible, bendable and stretchable arrays of III-nitride micro LEDs and devices using a photoelectrochemical (PEC) lift-off technique. The method involves growing the micro LEDs on a rigid substrate, flipping them onto a flexible substrate, and then removing the rigid substrate using a PEC etch. This allows separating the micro LEDs from the rigid host substrate while preserving the bond to the flexible substrate. The PEC etch selectively removes the sacrificial layer between the micro LEDs and host substrate due to dislocation sensitivity. This enables transferring the micro LEDs to a new substrate for flexible displays and other applications.

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