High-Temperature Annealing Effects on Atomically Thin Tungsten Diselenide Field-Effect Transistor

Abstract

Two-dimensional (2D) material-based devices are expected to operate under high temperatures induced by Joule heating and environmental conditions when integrated into compact integrated circuits for practical applications. However, the behavior of these materials at high operating temperatures is obscure as most studies emphasize only room temperature or low-temperature operation. Here, the high-temperature electrical response of the tungsten diselenide (WSe2) field-effect transistor was studied. It is revealed that 350 K is the optimal annealing temperature for the WSe2 transistor, and annealing at this temperature improves on-current, field-effect mobility and on/off ratio around three times. Annealing beyond this temperature (360 K to 670 K) adversely affects the device performance attributed to the partial oxidation of WSe2 at higher temperatures. An increase in hysteresis also confirms the formation of new traps as the device is annealed beyond 350 K. These findings explicate the thermal stability of WSe2 and can help design 2D materials-based durable devices for high-temperature practical applications.

Photocurrent modulation in a multilayer molybdenum ditelluride transistor

“…A shift of around 20 V in threshold voltage has been observed under forward and reverse sweep. The observation of the large hysteresis is quite common in 2D materials-based devices on SiO2 substrate and is commonly attributed to the traps at 2D material and SiO2 interface 11 .…”

Highly Efficient Perfect Vortex Beams Generation Based on All-Dielectric Metasurface for Ultraviolet Light

“…With the employment of large bandgap materials and the advancement of nano-fabrication technologies, recent years have witnessed a revolutionary development of miniaturized UV metasurfaces and their potential application in lithography [56], holography [55,57], information security [58], and many more sectors. Recently, hafnium oxide (HfO 2 ) and niobium pentoxide (Nb 2 O 5 ) have been employed to realize UV metasurfaces; however, meager throughput and the requirement of challenging fabrication processes hinder the applicability of these materials for nanophotonic devices [58][59][60]. Here, in this work, we utilized a bandgap-engineered silicon nitride (Si 3 N 4 ) material whose extinction coefficient (k) is reduced by optimizing the SiH 4 :N 2 gas ratio during deposition while maintaining the sufficient high refractive index (n) for the UV wavelengths.…”

Tungsten Supported Plasmonic Nanoscale Absorber for Solar Thermal Photovoltaics Applications

“…A remarkable interest has been sparked into renewable energy because of the increasing demand for energy [1][2][3][4][5][6][7][8]. These resources have the potential to furnish the modern energy demands while retaining features of cost-effectiveness and minimal negative environmental impact [9][10][11][12][13][14][15]. One of the most promising candidates of renewable energy is the solar energy, which can be transformed into heat, electricity, and photochemical reactions from continuous solar irradiation [16][17][18][19][20].…”