High-Sensitivity Flexible Photodetectors Based on Bi2Te3/Rubrene Schottky Heterojunction with Superior Interface

Recently, van der Waals organic–inorganic heterostructures (OIHs) have boosted significant interest in novel electronic and optoelectronic device applications due to their excellent properties. The integration of topological insulators and organic semiconductors to design novel OIHs may further improve device performance due to the presence of Dirac surface states at heterointerfaces. Thus, the high-quality rubrene (C42H28)/topological insulator (Bi2Te3) OIHs were developed using a simple and low-cost physical vapor deposition approach. Because of the atomically flat interface and robust Schottky potential, this newly designed OIH is very beneficial for the fabrication of optoelectronic devices with superior critical parameters. The transport results proved that the as-fabricated OIH photodetector (OIHPD) demonstrated excellent diode behavior in the dark and remarkable photovoltaic capabilities under light illumination. Due to the broadband absorption efficiency of the heterojunction, the detection range of the OIHPD can be broadened from visible to near-infrared lights. Notably, the device demonstrated a higher photoresponsivity of 852.7 A·W–1, a higher photodetectivity of 1.42 × 1013 Jones, ultrafast response speed with rising time (14 μs), and decaying time (16.2 μs) under a 1064 nm laser. These findings have proven potential opportunities for engineering the emerging next generation of broadband flexible photodetectors for boosting the optical detection domain.