Room-temperature extended short-wave infrared GeSn photodetectors realized by ion beam techniques
Shuyu Wen, Mohd Saif Shaikh, Oliver Steuer, Sławomir Prucnal, J. Grenzer, René Hübner, M. Turek, K. Pyszniak, Sebastian Reiter, Inga Anita Fischer, Yordan M. Georgiev, M. Helm, Shaoteng Wu, Jun‐Wei Luo, Shengqiang Zhou, Yonder Berencén
Abstract
GeSn alloys hold great promise as high-performance, low-cost, near- and short-wavelength infrared photodetectors with the potential to replace the relatively expensive and currently market-dominant InGaAs- and InSb-based photodetectors. In this Letter, we demonstrate room-temperature GeSn pn photodetectors fabricated by a complementary metal-oxide-semiconductor compatible process, involving Sn and P ion implantation and flash-lamp annealing prior to device fabrication. The fabrication process enables the alloying of Ge with Sn at concentrations up to 4.5% while maintaining the high-quality single-crystalline structure of the material. This allows us to create Ge0.955Sn0.045 pn photodetectors with a low dark current density of 12.8 mA/cm2 and a relatively high extended responsivity of 0.56 A/W at 1.71 μm. These results pave the way for the implementation of a cost-effective, scalable, and CMOS-compatible short-wavelength infrared detector technology.