An ultra -sensitive AlGaN/AlN/GaN/AlGaN photodetector: Proposal and investigation

In this paper, an AlGaN/AlN/GaN/AlGaN photodetector high electron mobility transistor is designed and simulated. The proposed structure incorporates an AlN spacer layer between the AlGaN and GaN layers to ensure good control of the two-dimensional gas, which improve, in turn, the device controllability. Besides, an overall figures of merit assessment is performed to highlights the design benefits. The suggested device provides a very high responsivity of 0.2641 A/W, a photocurrent of 1.1 × 10−7 A, a suitable (Iilumination/Idark) rejection of 10.8, and a high efficiency η of about 77%. The photo and dark current is at 2 V, 87 mA and 8 mA, respectively. A subthreshold slope (SS) of 53 mV/V and 42 mV/V, and a transconductance gm of 260 ms/mm and 180 ms/mm are obtained. The proposed photodetector springly outperforms the HEMT PD designs previously proposed in the literature. © 2020 Elsevier GmbH