Demonstration of a III-nitride edge-emitting laser diode utilizing a GaN tunnel junction contact

Abstract

We demonstrate a III-nitride edge emitting laser diode (EELD) grown on a (2021) bulk GaN substrate with a GaN tunnel junction contact for hole injection. The tunnel junction was grown using a combination of metal-organic chemical-vapor deposition (MOCVD) and ammonia-based molecular-beam epitaxy (MBE) which allowed to be regrown over activated p-GaN. For a laser bar with dimensions of 1800 µm x 2.5 µm, without facet coatings, the threshold current was 284 mA (6.3 kA/cm²) and the single facet slope efficiency was 0.33 W/A (12% differential efficiency). A differential resistivity at high current density of 2.3 × 10^-4 Ω cm² was measured.