Ultrafast UV AlGaN Metal–Semiconductor–Metal Photodetector With a Response Time Below 25 ps
Yiming Zhao, William R. Donaldson
Abstract
Aluminum-gallium-nitride photodetectors were successfully fabricated with micrometer-scale metal-semiconductor-metal structures and tested with ultrafast, UV laser pulses. The measurements were done with single-shot oscilloscopes. Pulse-broadening effects caused by the measurement system were systematically evaluated and reduced to resolve the intrinsic response time of the detector. The best-performing devices showed a response time of below 25 ps and dark currents below 20 pA. The devices showed linear response with the bias voltage and the laser energy.
Topics & Concepts
Materials sciencePhotodetectorOptoelectronicsUltrashort pulseOscilloscopeIndium gallium nitrideLaserResponse timeSemiconductorGallium nitrideOpticsRise timePhotoconductivityDetectorVoltageNanotechnologyPhysicsComputer graphics (images)Computer scienceLayer (electronics)Quantum mechanicsGaN-based semiconductor devices and materialsSemiconductor Quantum Structures and DevicesPlasma Diagnostics and Applications