Fabrication of multi-layer Bi₂Se₃ devices and observation of anomalous electrical transport behaviors

In this paper, we report on the fabrication of multi-layer bismuth selenide (Bi₂Se₃) devices by lithography process and their electrical transport characteristics studied at room temperature. The observation of a non-linear current-voltage characteristic is analyzed with various current transport mechanisms such as Schottky barrier, space-charge limited conduction (SCLC), Fowler-Nordheim (F-N) tunneling and Poole-Frenkel (P-F) conduction. The F-N tunneling via field emission current induced in high-voltage was found to be the dominant conduction mechanism which could responsible for the nonlinear behavior as compared to SCLC and P-F conduction phenomena. The charge traps present in the Bi₂Se₃ bulk causes SCLC and P-F conduction. A carrier mobility in Bi₂Se₃ is extracted as ~ 1220 cm² V⁻¹ s⁻¹. Our study further advances the understanding of the fundamental charge transport mechanisms appeared in Bi₂Se₃ which will be an essential parameter in the development of various electronic applications such as resistive memory switching and sensing devices.