Field effect transistor behavior of Bi2Se3 nanostructure prepared by laser ablation

Abstract

A new class of emerging materials known as topological insulators (TIs), such as bismuth selenide [Formula: see text], has an insulating band gap in the bulk and gapless surface state protected by its intrinsic time-reversal symmetry. These TI materials have attracted great attention because of their possible prospects in electrical and optical applications. In this work, we have prepared the [Formula: see text] nanostructure using the nanosecond (ns) pulse laser ablation in liquid environment to study the field effect transistor behavior. After the laser ablation, [Formula: see text] nanostructures were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV-visible spectroscopy to reveal the surface morphology and structural information. The field effect transistor (FET) has been fabricated using [Formula: see text] nanostructure by drop casting [Formula: see text] suspension between two gold electrodes having a gap of 3 [Formula: see text]m on [Formula: see text] substrate and tested for FET at various gate voltages. The SEM clearly shows the formation of [Formula: see text] nanoparticles of different size varying from 20 nm to 30 nm after the ns laser ablation treatment. This result is supported by UV-visible spectra, as indicated by the enhancement in absorption band. The experimental results showed that charge conduction due to electrons as charge carriers were possible in [Formula: see text] nanoparticle FET. This work provides another approach to use [Formula: see text] nanoparticle FET for the applications in optoelectronic devices.