Abstract: III-V micro light-emitting diodes (LEDs) are fabricated using a photoelectrochemical (PEC) etch. A sacrificial layer and III-V device layers are epitaxially grown on a host substrate, wherein the III-V device layers are patterned to form the micro-LEDs. The sacrificial layer is removed by a photoelectrochemical (PEC) etch, so as to fully or partially separate the micro-LEDs from the substrate, before or after the micro-LEDs are bonded to a submount or intermediate substrate. The micro-LEDs may be bonded to a submount with a polymer film deposited thereon, wherein the polymer film with the micro-LEDs is subsequently delaminated from the submount. Alternatively, the intermediate substrate may be a transfer medium, wherein the micro-LEDs are separated from the host substrate by mechanical fracturing, and then bonded to a second substrate, after which the intermediate substrate is removed, wherein a third substrate may be bonded to exposed surfaces of the transferred micro-LEDs.