Phototransistors: Giant Photoamplification in Indirect‐Bandgap Multilayer MoS₂ Phototransistors with Local Bottom‐Gate Structures (Adv. Mater. 13/2015)

Abstract

Woong Choi, Sunkook Kim, Y. Yoon, and co‐workers present local‐gate multilayer MoS2 phototransistors with outstanding photoresponsivity of up to 342.6 A W−1, which is 3 orders of magnitude higher than that of global‐gate multilayer MoS2 phototransistors, as described on page 2224. These results suggest that high photoresponsivity can be achieved in indirect‐bandgap multilayer MoS2 phototransistors by optimizing the optoelectronic design.

Directly visualizing carrier transport and recombination at individual defects within 2D semiconductors

“…The unique optoelectronic properties of two-dimensional semiconductors (2DSCs), such as the transition metal dichalcogenides (TMDs), make them attractive candidates for use in a variety of electronic and photonic devices, including photovoltaic cells, [1][2][3][4][5][6][7] photodetectors, [8][9][10] and LEDs. 11,12 The inherent 2D structure of these materials allows them to be prepared as ultrathin films down to the monolayer limit, which can serve as flexible active layers with favorable optical properties as compared to the bulk material.…”

Solution‐processed high‐k oxide dielectric via deep ultraviolet and rapid thermal annealing for high‐performance MoS2 FETs

“…These intriguing characteristics have driven intensive research efforts to address fundamental electrical and optical properties , to improve electrical contacts , and to optimize interface layers . Furthermore, various phototransistor structures, biosensors, and integrated circuit components for broad applications have been demonstrated based on mono‐ and multi‐layered MoS 2 field‐effect transistors (FETs) . Recently, large‐area synthesis of single‐ and few‐layered MoS 2 has been reported using high‐temperature vacuum deposition methods , although significant advances still required to achieve high‐quality MoS 2 film.…”

Dynamic Control of High-Range Photoresponsivity in a Graphene Nanoribbon Photodetector

“…We believe that our device is expected to operate at higher frequencies over 50, 000 Hz, and the accurate value of response speed is not clear due to the limitation of the measuring equipment. It was noted that the GNR photodetector run much faster than most photodetectors based on graphene and other 2D TMDs [28][29][30][31]. It is believed that the fast photocurrent switching can be attributed to the ultrahigh carrier mobility of the GNRs of such width and the strong external electric field.…”