In x Ga 1−x N light emitting diodes on Si substrates fabricated by Pd–In metal bonding and laser lift-off

Abstract

Indium–gallium nitride (InxGa1−xN) single-quantum-well (SQW) light emitting diodes (LEDs), grown by metalorganic chemical vapor deposition on sapphire, were transferred onto Si substrates. The thin-film InxGa1−xN SQW LED structures were first bonded onto a n+-Si substrate using a transient-liquid-phase Pd–In wafer-bonding process followed by a laser lift-off technique to remove the sapphire growth substrate. Individual, 250×250 μm2, LEDs with a backside contact through the n+-Si substrate were then fabricated. The LEDs had a typical turn-on voltage of 2.5 V and a forward current of 100 mA at 5.4 V. The room-temperature emission peak for the InxGa1−xN SQW LEDs was centered at 455 nm with a full width at half maximum of 19 nm.