High performance short wave infrared photodetector using p-i-p quantum dots (InAs/GaAs) validated with theoretically simulated model

We demonstrate the highly promising p-i-p InAs/GaAs quantum dots based infrared photodetector (QDIP) which utilize intra-valence band hole transitions as against electron transitions operating at high temperatures. The photoluminescence spectroscopy at 9 K exhibited the ground state emission peak at 986 nm. The spectral response measured reveals the short wave infrared (SWIR) detection with a high-intensity peak at a wavelength of 2 mu m. The measured dark current density at 77 K was 0.448 A/cm(2) for an applied voltage of -1 V. The spectral response peak and blackbody signal measurements were recorded up to 245 and 270 K, respectively. Fabricated detector exhibited high confinement energy of 82.1 meV measured using temperature dependent current-voltage characteristics. We report high temperature infrared detection at 225 K in the short wave infrared regime with a peak responsivity of 3.813 A/W and a specific detectivity of 2.189 x 10(10) cmHz(1/2) /W. In order to study the electronic properties of InAs/GaAs QD, a theoretical model is developed in which Vegard's law is applied to solve 3D-Schrodinger equation, which makes use of concentration-dependent equations for light hole and heavy hole masses instead of the effective mass approximation of holes. This study demonstrates the necessity of exploring hole-transitions rather than the conventional electron-transitions in QDIPs in order to achieve high temperature of operation and improved device efficiency. (C) 2019 Elsevier B.V. All rights reserved.