InSb Mid-Infrared Photon Detector for Room-Temperature Operation

Abstract

We developed a small InSb mid-infrared (2–7 µm wavelength range) photon detector that operates at room temperature. The photodiode was made from (hetero epitaxial) InSb layers that were grown on a semi-insulating GaAs substrate by molecular beam epitaxy. To suppress the effects of the diffusion current of the p–i–n photodiode, we used an AlInSb barrier layer that raises the resistance of the photodiode. We also optimized the device's doping concentration and the infrared incidence window structure. These optimization steps realized high photoelectric current output in a room-temperature environment. We also increased the signal-to-noise ratio of the detector by connecting multiple photodiodes in series. The size of this detector is 1.9×2.7×0.4 mm3 and the detectivity is 2.8×108 cm Hz1/2/W at 300 K. This is a practical IR detector that can be used in general signal amplification ICs.

Monolithic Integration of an Active InSb-Based Mid-Infrared Photopixel With a GaAs MESFET

“…The photo-response was detected using a current preamplifier connected to the node V source . The peak in the response was at 5.1 µm with a full width at half maximum (FWHM) of 2.6 µm, which is consistent with results from InSb photodiodes operating at room temperature [29]. The sudden drop of the curve at approximately 4.2 µm is because of the absorption caused by CO 2 in the atmosphere.…”

“…Previously published work on InSb photodiodes grown on GaAs substrates yielded values of 0.46×10 -3 Ω cm 2 for a 30 μm diameter circular diode fabricated on an epi-structure without a barrier layer [28]. A higher value of 0.92×10 -3 Ω cm 2 was reported for a 14.5 μm square diode fabricated on a structure where a barrier layer was introduced [29]. InSb photodiodes grown on InSb (100) substrate produced R 0 A values, at room temperature of approximately 1×10 -3 Ω cm 2 [30].…”

High-quality InSb growth by metalorganic vapor phase epitaxy

“…Highquality InSb films are very important in these sensors, and InSbbased devices are mainly being developed by using molecular beam epitaxy (MBE) [3][4][5]. Although metalorganic vapor phase epitaxy (MOVPE) is more suitable for mass production, there are few reports of high quality InSb growth by MOVPE.…”

AlInSb Mid‐Infrared LEDs of High Luminous Efficiency for Gas Sensors

“…We have previously reported the mid‐infrared photon detector and LED based on InSb hetero‐epitaxial structure . Compared to the conventional thermal detectors such as thermopiles and pyro‐electric detectors with tungsten lamps, this quantum photon detector/emitter pair works preferably for NDIR gas sensing applications, though the wavelength was not suited for CO 2 (4.2 μm) detection.…”