Schottky metal-semiconductor-metal photodetectors on GaN films grown on sapphire by molecular beam epitaxy

摘要

We report high-performance back-to-back Schottky metal-semiconductor-metal photodetectors fabricated on GaN epitaxial layers grown by molecular beam epitaxy. The photodetectors exhibit very low dark current (>1 pA at 30 V) and high external quantum efficiency (<70%). Medici simulation of the depletion region width indicated an absence of photoconductive gain. The temporal response has also been characterized.