High-performance CsGeBr3 perovskite/ WS2 Nano-Flakes Field-Effect Transistor at high temperature

This study explores the current-voltage characterization of tungsten disulfide Nano-Flakes (WS2 NFs) Field-Effect-Transistor (FET) under various temperatures with a simple back-gate device structure. Due to the non-toxic nature of inorganic perovskite CsGeBr3 (CGB), this material is applied to fabricate a CGB/WS2 FET by drop-casting of lead-free perovskite CGB on the WS2 NFs FET. The characterization of fabricated two FET devices has been performed under the illumination of a laser source (at a wavelength of ∼532 nm) with three different temperatures (298°, 313°, and 333° K). The output and transfer characteristics of CsGeBr3/WS2 NFs FET illustrate that CGB is very effective in boosting the photocurrent and performance of the FET. For each two FET devices, increasing the temperature led to a decrease in drain-source current (Ids), whereas the rate of Ids reduction in CGB/WS2 NFs FET is roughly two times less than WS2 NFs FET. The results demonstrate that the conductivity and Ids of the CGB/WS2 NFs FET have been doubled compared to the bare WS2-NFs FET. Most importantly, the CGB/WS2 NFs FET shows higher external quantum efficiency, photo-responsivity, and detectivity in comparison with the WS2 NFs FET. The superior photo-sensing properties of the CGB/WS2 NFs FET are very promising to extend the two-dimensional optoelectronic devices with excellent performance.