High-Resolution Micro-LED Display Production

Monolithic microLED display fabrication method to avoid organic material residue in vias that can cause defects. The method involves isolating the LED with a base layer before processing the OTFT. This allows consistent etching of vias through the isolated base layer to connect the LED and OTFT without organic material filling. After OTFT processing, a final via is etched through both the base layer and any passivation layer to complete the connection. This avoids organic material deposition during OTFT processing that can impede subsequent passivation layer deposition.

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Flexible thin film GaN-based nanocolumn LED array micro-display device and manufacturing method. The device has a flexible substrate with a mask having periodic openings. GaN LED nanocolumns are selectively grown inside the openings using MOCVD. The LEDs have cylindrical or hexagonal shapes. The nanocolumn LED array is covered by a transparent conductor and flexible material. Electrodes are added on the flexible layer. This allows flexible, high resolution, high efficiency LED microdisplays with improved yield compared to traditional top-emitting microLEDs.

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Micro LED display device and manufacturing method that prevents moisture and dust intrusion to improve reliability. The micro LED display has a pixel layer with individual micro LEDs facing the circuit substrate. A support structure extends from the substrate to the pixel layer and protrudes above it. This forms a space between the support and pixel layer. A connection layer is filled in this space and covered by a protection layer. This enclosure around the pixels prevents moisture and dust from reaching the LEDs and degrading their performance.

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LED display with improved chip attachment method to prevent positional deviations during welding. The display is manufactured by mounting LED chips on a substrate, filling the gaps between the chips with a curable material, exposing and developing the material to create grooves exposing the chip electrodes, filling those grooves with conductive paste, and adding an insulating layer. This prevents solder paste beads from moving the chips during soldering. The display has a flush filling layer, exposed chip electrodes, filled grooves connecting to the chips, and an insulating layer covering the filled grooves.

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Preparing smaller-sized micro LED chips for higher resolution displays by patterning a mask on the second semiconductor layer and etching to limit chip size. This involves forming a patterned silicon oxide mask on the second semiconductor layer, using the mask to deposit a transparent conductive layer in certain areas and etch the second semiconductor layer in others. This creates micro LED chips with smaller pixel pitches and higher resolution.

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Display module with improved bonding accuracy for micro LEDs. The module has a substrate with a region around the pixel area having higher surface energy. When bonding micro LEDs to the substrate electrodes, an adhesive layer is temporarily cured to move the excess adhesive from the pixel area to the higher surface energy region. This reduces thickness variation and misalignment of the micro LEDs compared to uniform adhesive. The higher surface energy area helps hold the micro LEDs in place during curing. The thinner adhesive between the electrodes reduces voids and gaps.

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Micro LED display device with simplified manufacturing by using a transparent substrate with pre-transferred micro LEDs, and forming the TFT electrodes on top using an organic TFT layer instead of transferring the micro LEDs onto TFT electrodes. This allows easier micro LED transfer and simplifies the manufacturing process compared to conventional micro LED displays. The device has a transparent substrate with exposed micro LED anode and cathode electrodes, a signal supply line layer on top, and an organic TFT layer with driving transistors on the supply lines.

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Integrated display wafer and preparation method for low-cost, high-performance microLED displays with improved yield and reduced cost compared to conventional microLED displays. The method involves integrating the microLED chips, electrodes, and isolation layers on a temporary substrate, then transferring the entire integrated wafer to a final display substrate. This eliminates the need for individual microLED chip transfer and testing, reducing defects and costs. The integrated wafer has layers of microLED chips, isolation layers, electrodes, and a temporary substrate.

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A method for selectively transferring microLEDs to fabricate displays with higher yield and lower cost compared to traditional methods. The method involves covering the microLED wafer with an adhesion layer, depositing the backplane on the adhesion layer aligned with some exposed microLEDs, then removing the backplane with those microLEDs to a display substrate. This allows selective transfer of working microLEDs without individually moving them. The adhesion layer prevents damage to the microLEDs and backplane during removal. This reduces transfer errors compared to pick-and-place or adhesive films. The display can have monolithic integration of microLEDs and backplane on the same substrate, but allows repair of defective microLEDs by selective transfer.

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MicroLED display with on-chip integrated transistor driver circuit to reduce integration complexity and manufacturing cost compared to bonding MicroLED wafers to separate thin film transistor backplanes. The display structure has a pixel array with each pixel containing a MicroLED chip above the substrate. The MicroLED chip has layers like buffer, N-GaN, MQW, P-GaN, and transparent electrode. The transistor driving circuit is integrated into the first packaging layer covering the MicroLEDs. The transistors are oxide thin film transistors integrated on-chip. This eliminates the need for separate backplane bonding and alignment steps, simplifying manufacturing.

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Micro LED manufacturing method that efficiently implements a structure connecting the pixel and transistor elements, and promotes miniaturization by reducing the thickness. The method involves forming patterns, pixels, upper electrodes, lower electrodes, and protective support layers. The upper electrodes connect pixels in the same row/column, and via holes expose them. The lower electrodes connect pixels perpendicularly. This allows efficient pixel-to-transistor connection without stacking. The protective support surrounds the pixels and electrodes. The method reduces thickness by exposing lower pixel surfaces and forming lower electrodes there.

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Method to manufacture microLED displays with reduced production cost and improved yield compared to existing methods. The method involves using alkyl precursors to grow semiconductor layers for microLEDs directly on a display substrate without the need for a separate sapphire or other growth substrate. This eliminates the high-temperature, high-cost sapphire transfer step. The alkyl precursors allow epitaxial growth on the display substrate using lower temperatures. The alkyl precursors can be converted into the corresponding semiconductor materials during growth. The alkyl-assisted growth also allows tuning of composition and doping levels to optimize LED performance.

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A method for manufacturing a micro LED character display chip with improved isolation between the control metal wires and the LED sidewalls. The method involves depositing a thicker silicon dioxide insulating film on the LED sidewalls compared to the sidewall depth. This provides better electrical isolation between the metal wires and LED sidewalls when crossing over. The thicker insulating film prevents short circuiting of the control wires and LEDs.

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Preparing microLED array substrates without using photoresist to avoid issues like contact failures and damage during etching. The method involves covering the anode and cathode contact layers with hardmask layers instead of photoresist. These hardmask layers are patterned to define the pixel areas. After patterning, the substrate is bonded and the original substrate removed. The cathode hardmask is then etched to connect the anode pattern. This eliminates the need for photoresist and subsequent cleaning, preventing contact issues and sidewall damage.

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Method for manufacturing LED displays with micro/nano LEDs that allows easy assembly of small LEDs on a substrate. The method involves forming a base circuit on the substrate, covering it with an electrode layer, forming an insulating layer over the entire area, creating a trench-shaped LED array area in the insulating layer, and supplying LEDs in fluid form. Applying voltage to the electrodes aligns the LEDs in the array. The insulating layer is removed to expose the LED contacts, which are then connected to the electrodes. This allows precise positioning of micro/nano LEDs without physically transferring them.

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Micro LED display panel with integrated multi-color LED pixels to improve efficiency and reduce production cost compared to assembling monochrome LEDs. The method involves forming a stack of layers containing different color LED materials on a substrate, patterning them to expose the bottom conductive layer, then selectively etching to expose sidewalls and form separate pixels with stacked LED structures. This allows integrated multi-color pixels in each display area.

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Wafer-level full-color LED display device with improved yield and reliability by eliminating issues with conductive lines breaking during manufacturing. The device is fabricated by alternating LED structures in rows and columns with trenches between them. Insulating layers are filled in the trenches to level the LED structures and fill the height difference. Circuit layers are then built on top of the leveled structures. This prevents conductive lines from breaking as they climb over the trench steps during manufacturing.

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Simplifying the process of making ultra-high resolution microLED displays by using ion implantation to isolate pixels instead of complex photolithography steps. The method involves forming a metal bump array on the microLED epitaxial wafer using electroplating. Then, a photoresist pattern is used to mask the metal bumps during ion implantation to isolate the pixels. This avoids the need for multiple steps of photolithography and etching for pixel definition. The metal bumps also serve as seed layers for electroplating.

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Micro LED layout structure and manufacturing method for augmented reality (AR) and mixed reality (MR) displays in wearable devices like smart glasses. The layout involves placing Micro LEDs on the edges of each display unit while leaving a transparent region in the center. The pixel driver circuits are under the edge Micro LEDs. This allows AR/MR devices with transparent displays that still have LED pixels for augmentation. The manufacturing involves forming the driver circuits and first transparent layer on the edge, then placing Micro LEDs on that layer to connect to the circuits beneath.

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Manufacturing microLED devices using a self-alignment process that addresses issues like mask intolerance, pattern shrinkage, sidewall damage, and protection layer opening problems during microLED fabrication. The method involves several steps: 1. Forming a protection layer on the microLED structure. 2. Etching the microLED structure using dry etching techniques like ICP. This shrinks the photoresist mask and introduces sidewall damage. 3. Removing the photoresist mask. 4. Forming a self-aligned dielectric layer on the microLED structure using selective deposition techniques. This is done by selectively depositing the dielectric layer only on the microLED sidewalls, leaving the top and bottom surfaces exposed. This is achieved by using a mask with openings that align with the microLED sidewalls, but not the top and bottom surfaces. This self-aligned

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