Topological Insulator Bi₂Se₃/Si-Nanowire-Based p–n Junction Diode for High-Performance Near-Infrared Photodetector

Abstract

Chemically derived topological insulator BiSe nanoflake/Si nanowire (SiNWs) heterojunctions were fabricated employing all eco-friendly cost-effective chemical route for the first time. X-ray diffraction studies confirmed proper phase formation of BiSe nanoflakes. The morphological features of the individual components and time-evolved hybrid structures were studied using field emission scanning electron microscope. High resolution transmission electron microscopic studies were performed to investigate the actual nature of junction whereas elemental distributions at junction, along with overall stoichiometry of the samples were analyzed using energy dispersive X-ray studies. Temperature dependent current-voltage characteristics and variation of barrier height and ideality factor was studied between 50 and 300 K. An increase in barrier height and decrease in the ideality factor were observed with increasing temperature for the sample. The rectification ratio (I/I) for SiNWs substrate over pristine Si substrate under dark and near-infrared (NIR) irradiation of 890 nm was found to be 3.63 and 10.44, respectively. Furthermore, opto-electrical characterizations were performed for different light power intensities and highest photo responsivity and detectivity were determined to be 934.1 A/W and 2.30 × 10 Jones, respectively. Those values are appreciably higher than previous reports for topological insulator based devices. Thus, this work establishes a hybrid system based on topological insulator BiSe nanoflake and Si nanowire as the newest efficient candidate for advanced optoelectronic materials.

Ultrahigh Stability 3D TI Bi2Se3/MoO3 Thin Film Heterojunction Infrared Photodetector at Optical Communication Waveband

“…The maximum on–off ratio of this device is 5.32 × 10 4 @ 650 nm, which is more than two orders of magnitude higher than similar devices previously reported ( Table 1 ). Therefore, the device has more distinguished I – V rectification characteristics than other reported devices based on TIs materials. In Bi 2 Se 3 /MoO 3 heterojunction, the Fermi energy level ( E f ) of N‐type material Bi 2 Se 3 is −5.3 eV and the bandgap is 0.3 eV.…”

“…By measuring the response time of the device, the optical response performance is deeply studied. Impressively, the response time reached a staggering 62 µs, better than many previously reported IR devices at room temperature . The heterogeneous structure based on Bi 2 Se 3 has great application potential in the field of photoelectric detection, which provides a feasible direction for the application of 3D TIs materials.…”

“…In order to solve the problem, it is appropriate choice to find suitable materials to manufacture heterojunction with Bi 2 Se 3 . Lately, Das et al prepared Bi 2 Se 3 /Si nanowire heterojunction photodetector, which had a 932 A W −1 responsivity ( R i ) with a response time of about 41 ms at NIR region . Yang et al fabricated 3D TIs/organic thin film heterojunction devices, whose R i and response time reached 14.89 A W −1 and 1.89 ms at 650 nm .…”

Ultrabroadband, Large Sensitivity Position Sensitivity Detector Based on a Bi2Te2.7Se0.3/Si Heterojunction and Its Performance Improvement by Pyro‐Phototronic Effect

“…Besides, Bi 2 Te 3 and Bi 2 Se 3 are all stoichiometric rhombohedral materials with quintuple stacked layered structure and relatively weak layer‐to‐layer van der Waals coupling, as shown in Figure a. Therefore, high‐quality thin films can be easily deposited on the Si substrate via different techniques, making further basic studies and potential applications possible. More importantly, it was suggested that the construction of Bi 2 Se 3 on Si could introduce a very high Schottky barrier of ≈0.34 eV at the interface, which can be used to accelerate the separation of photo‐excited carriers in Si or Bi 2 Se 3 and inhibit their recombination simultaneously, thus the outstanding photoelectric responses were usually obtained.…”

“…[21][22][23]25,27] However, for traditional PDs, researchers mainly concentrated on the longitudinal separation of photo-generated carriers in the interface of the heterojunctions, while the excellent surface transport properties were usually neglected or not well utilized. [21][22][23]25,27] However, for traditional PDs, researchers mainly concentrated on the longitudinal separation of photo-generated carriers in the interface of the heterojunctions, while the excellent surface transport properties were usually neglected or not well utilized.…”