Controlled Synthesis of Large-Scale Uniform Bi<sub>2</sub>Se<sub>3</sub> Thin Films for Self-Powered and Broadband Photodetection
Han Tang, Siwei Luo, Zekun Rong, Xiang Qi, Kai Huang, Jun Li, Xixi Huang, Zhiyuan Tang, Jianxin Zhong
Abstract
High Resolution Image Download MS PowerPoint Slide Bi 2 Se 3 has drawn substantial attention due to its high carrier mobility and superior thermal conductivity. In this study, large-scale and high-quality Bi 2 Se 3 thin films were successfully synthesized via the low-pressure vapor deposition method, and the growth mechanism was investigated comprehensively. Furthermore, photodetectors based on Bi 2 Se 3 films were fabricated, and the photoelectric properties of the films were investigated. The results demonstrated that the Bi 2 Se 3 photodetector based on SiO 2 /Si exhibited high responsivity (15.2, 41.3, 38.9, and 20.7 μA/W) from visible (VIS) to near-infrared (NIR) wavelengths and can be performed without any bias voltage. To explore the potential application in flexible photodevices, Bi 2 Se 3 films were directly deposited on a polyimide (PI) substrate to create a flexible photodetector. Similar to the rigid detector, the flexible photodetector exhibited self-powering ability and high responsivity (21.1 μA/W). Moreover, the as-fabricated flexible photodetector exhibited excellent mechanical flexibility and stable photoresponse after the bending test and curvature test. Our work provides valuable experience and lays a solid foundation for the preparation of large-scale and high-quality Bi 2 Se 3 films. It also highlights the great potential of vapor deposited atomic layer Bi 2 Se 3 films in the fields of multifunctional detectors.