Enhancement in Peak Detectivity and Operating Temperature of Strain-Coupled InAs/GaAs Quantum Dot Infrared Photodetectors by Rapid Thermal Annealing

Abstract

We report the effects of rapid thermal annealing on the optical, structural, and device properties of 30 layer straincoupled InAs/GaAs quantum dot infrared photodetectors. Stability in the photoluminescence peak is observed for annealing up to 800°C, which has not been previously reported. Cross-sectional transmission electron microscopy images show preservation of quantum dots is observed up to 800°C. Device with total capping thickness of 150 nm annealed at 750°C exhibit a fivefold enhancement in spectral intensity compared to as-grown devices and increase in the temperature of detector operation is observed from 100 to 140 K from the same device. The annealed devices exhibited a single-order enhancement in peak detectivity compared to as-grown quantum dot infrared photodetector. Index Terms-Infrared detectors, photodetectors, photoluminescence, quantum dots. Subhananda Chakrabarti (M'06) received the M.Sc. and Ph.D. degrees from the from 2005 to 2006, and a Senior Researcher (RA2) with the University of Glasgow, Glasgow, U.K., from 2006 to 2007. He joined the Department of Electrical Engineering, IIT Bombay, Mumbai, India, in 2007.He has extensively researched molecular beam epitaxial growth, characterization, and fabrication of semiconductor optoelectronic materials and devices, such as quantum dot laser, intersubband detectors, and vertical-cavity surface-emitting lasers. He has authored or coauthored more than 160 papers in journals and conferences. He has also coauthored a couple of book chapters on intersubband quantum dot detectors.

Multi-inch single-crystalline perovskite membrane for high-detectivity flexible photosensors

“…Under the lowest measured incident light, power density achieves 8 × 10 − 5 mW cm − 2 , and the highest R , EQE, and D * are calculated to be 98.17 A W − 1 , 2.65 × 10 4 % and 1.62 × 10 15 cm Hz 1/2 W − 1 (Jones), respectively. Note that the extraordinarily high D * value of the present device (exceeding 10 15 cm Hz 1/2 W − 1 ) is among the record high reported for the perovskite photosensors so far, and it is even higher than that of devices based on single-crystalline silicon 56 , InGaAs 57 , GaAs 58 , CdTe 59 , and GaN 60 , demonstrating much superior quality of the 2D layered (PEA) 2 PbI 4 single-crystalline perovskite membrane material.…”

“…It is found that the present photosensor shows very high external quantum efficiency (EQE) as much as 26,530%, responsivity ( R ) as high as 98.17 A W −1 , and detectivity ( D *) as large as 1.62 × 10 15 cm Hz 1/2 W −1 (Jones). It should be noted that this detectivity value is not only among the highest detectivity reported to date for all single-crystalline and thin-film perovskite photosensors 56 , it is even higher than devices based on the state-of-the-art material including single-crystalline silicon 56 , InGaAs 57 , GaAs 58 , CdTe 59 , and GaN 60 . Moreover, the flexible membrane photosensor shows excellent mechanical stability.…”