AlGaN-channel high electron mobility transistors(HEMTs)were operated as visible-and solar-blind photodetectors by using GaN nanodots as an optically active floating gate.The effect of the floating gate was large enoug...AlGaN-channel high electron mobility transistors(HEMTs)were operated as visible-and solar-blind photodetectors by using GaN nanodots as an optically active floating gate.The effect of the floating gate was large enough to switch an HEMT from the off-state in the dark to an on-state under illumination.This opto-electronic response achieved responsivity>10^8 A∕W at room temperature while allowing HEMTs to be electrically biased in the offstate for low dark current and low DC power dissipation.The influence of GaN nanodot distance from the HEMT channel on the dynamic range of the photodetector was investigated,along with the responsivity and temporal response of the floating gate HEMT as a function of optical intensity.The absorption threshold was shown to be controlled by the AlN mole fraction of the HEMT channel layer,thus enabling the same device design to be tuned for either visible-or solar-blind detection.展开更多
基金Sandia National LaboratoriesDefense Advanced Research Projects Agency(DARPA)+1 种基金National Technology and Engineering Solutions of SandiaU.S.Department of Energy’s National Nuclear Security Administration(DE-NA-0003525)
文摘AlGaN-channel high electron mobility transistors(HEMTs)were operated as visible-and solar-blind photodetectors by using GaN nanodots as an optically active floating gate.The effect of the floating gate was large enough to switch an HEMT from the off-state in the dark to an on-state under illumination.This opto-electronic response achieved responsivity>10^8 A∕W at room temperature while allowing HEMTs to be electrically biased in the offstate for low dark current and low DC power dissipation.The influence of GaN nanodot distance from the HEMT channel on the dynamic range of the photodetector was investigated,along with the responsivity and temporal response of the floating gate HEMT as a function of optical intensity.The absorption threshold was shown to be controlled by the AlN mole fraction of the HEMT channel layer,thus enabling the same device design to be tuned for either visible-or solar-blind detection.
