| 초록 |
2D materials such as layered metal chalcogenides (LMDs), graphene, black phosphorous (BP), h-BN as well as layered oxychalcogenides, have been intensively studied in electronics, photonics, and optoelectronics due to their extraordinary properties. Recently, Bi2O2Se as a novel oxychalcogenides reported by Peng et al. with tremendous hall mobility (~ 450 cm2V-1S-1 at RT and ＞ 20,000 cm2V-1s-1 at 1.9 K), non-zero bandgap (~ 1 ev), and high air stability. Due to its excellent performance, it has great attractive potential in device applications, e.g., field effect transistor (FET), optoelectronics, thermoelectrics, and memristors. Among these, optoelectronics, more specifically photodetectors, are one of the most intensively studied applications, because it shows ultra-fast photoresponse, detectivity, broadband from visible to IR. Despite many merits of Bi2O2Se and other 2D materials, there are some obstacles, which are synthesis of large-scale thin films and relatively complex device fabrication process, on conventional synthesis methods such as hydrothermal, chemical vapor deposition (CVD), mechanical exfoliation (ME). Although previous studies already reported that the growth of large-scale 2D thin films using pulsed laser deposition (PLD), complex lithography process which contains patterning, lift-off, and deposition of electrode is essential to fabricate the electronic device. Herein, we fabricate a simple device fabrication process with the growth of centimeter-scale 2D Bi2O2Se thin films via PLD method. Also, the structural properties were confirmed by Raman, x-ray photoelectron spectroscopy (XPS), and x-ray diffraction (XRD). Finally, we fabricate device with patterning-free process and its optical characteristics were measured using monochromator. |
