Figure 1

Schematic illustrations and images corresponding to the steps for forming, assembling, and repairing ultrathin μLEDs fabricated from GaN on sapphire substrates: (a) μLED wafers including defective chips (left: schematic; right: optical microscopy image). (b) Selective pick-up of the array of good chips from the μLED wafer to stamp by UV PE (left: schematic; right: optical microscopy image). (c) Imprinting the array of good chips to the PI board substrate that coated the functional layer (left: schematic; right: optical microscopy image). (d) Selective pick-up of the array of good chips for repair from μLED wafer to stamp according to the coordinates of empty spaces on the PI board substrate (left: schematic; right: optical microscopy image). (e) Align-imprinting the array for repairing the array on the PI board substrate (left: schematic; right: optical microscopy image). (f) SEM images of the transferred array on the PI board substrate.