Abstract:
Uncooled photodiodes based on GaSb/GaAlAsSb heterostructures for recording pulsed infrared radiation in the spectral range of 0.9–1.8 $\mu$m are developed and studied. The GaSb active region is prepared using lead as a neutral solvent in order to reduce the concentration of natural acceptors. The capacitance of the photodiodes with a sensitive-area diameter of 300 $\mu$m is 115–135 pF without bias and 62–70 pF with a reverse bias of 1.5 V. The response speed of the photodiode measured in the photovoltaic mode using an InGaAsP/InP laser with a radiation wavelength of 1.55 $\mu$m is as high as $\tau_{0.1-0.9}$ = 42–60 ns. It is demonstrated experimentally that the fabricated photodiodes can be used without cooling to detect pulsed laser and LED radiation in the near-IR spectral region.