Silicon Based GeSn p-i-n Photodetector for SWIR Detection

We reported an investigation of GeSn-based p-i-n photodetectors (PDs) with a Ge <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.92</sub> Sn <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.08</sub> active layer grown on n-type Si (100) substrate using molecular beam epitaxy (MBE). The GeSn photodetector achieved a wide spectrum detection whose cutoff wavelength can reach to 2.3 μm. The PDs exhibited a high performance near 2.0 μm with a responsivity of 93 mA/W and a dark current of 171 μA under a reverse bias of 1 V at room temperature. This work represented a promising technology to develop Si-based short-wave infrared (SWIR) photodetectors.