High Consistency Micro-LED Manufacturing

(Summary) Manufacturing method for micro LED displays that reduces time for transferring the micro LEDs from the growth substrate to the final display substrate while preventing non-uniformity of luminous properties. The method involves segmenting the micro LED regions on the growth substrate and simultaneously transferring the segmented regions to separate display substrates. This allows efficient transfer of all the micro LEDs without waiting for simultaneous transfers from the growth substrate. The segmented arrangements on the display substrates also prevent luminance and color uniformity issues.

(Summary) Method for transferring micro-LEDs to a receiving substrate to enable micro-LED manufacturing of high-quality displays. It involves using a laser to lift off micro-LEDs from the original substrate and transfer them to a receiving substrate. An anisotropic conductive layer makes electrical contact with the receiving substrate pads. This avoids complications of pick-up tools and multiple transfers. The laser lift-off enables easy transfer without damaging the micro-LEDs.

(Summary) Method of fabricating microLED displays with improved alignment and yield when flip-bonding microLEDs onto submounts. The method overcomes misalignment caused by different thermal expansion coefficients between the microLED's sapphire substrate and the silicon submount. Instead of standard flip-bonding that heats solder bumps to melt and connect the microLED electrodes to the submount contacts, the improved method uses lasers to selectively heat the solder bumps without heating the substrates. This prevents misalignment due to different thermal expansion.

(Summary) Micro LED lighting device with a repair mechanism to improve manufacturing yield and enable in-situ repair. The device has a redundant micro LED that can be activated if the main micro LED fails. The redundant LED has separate electrical connections that can be switched on to bypass the main LED. The repair mechanism allows the redundant LED to be activated and connected when the main LED fails, providing a backup lighting source. This allows failed micro LEDs to be repaired by switching to the redundant LED. The repair mechanism improves yield and product reliability.

(Summary) A light-emitting unit for displays that uses micro-LEDs and bonding pads with specially shaped pins for improved yield and uniformity. The micro-LED has a strip-like element pin with length>width and nonzero angle to the strip-like bonding pin. This allows easier alignment and welding between the pins with lower precision. The strip shape gives a larger tolerance for pin misalignment compared to point-like pins.