Room-temperature near-infrared photodetectors based on GeTe film grown by pulsed laser deposition method

GeTe, with its narrow band gap and excellent carrier mobility, is a promising material for near-infrared (NIR) photodetector. In this paper, the NIR photoelectric properties of GeTe films grown by pulsed laser deposition were systematically studied. The microstructures of GeTe films can be controllably obtained by adjusting the substrate temperature. The photodetectors based on the GeTe films grown at 250 celcius present excellent photo-electric properties with a responsivity of 0.98 A W-1, a detectivity of 1.08 x 109 Jones, and external quantum efficiency of 114.1% under the 1064 nm laser illumination at room temperature. Such excellent properties were primarily attributed to the interaction of hole trapping and electron-hole pair recombination. These photoelectric properties indicate that GeTe films have immense potential for NIR photodetection devices.