Mechanisms of Current Fluctuation in High-Mobility p-Type Tellurium Field-Effect Transistors

This article utilizes low-frequency noise (LFN) measurements to evaluate the stability of tellurium (Te) field-effect transistor (FET). Our results show that LFN for Te FET on hexagonal boron nitride/silicon dioxide (h-BN/SiO₂) tracks the trends of flicker noise (1/f noise) and decreases with increasing overdrive voltages, which is ascribed to the change of dominant carriers and the fluctuation of surface trap density. Compared with Te FET on SiO₂, Te FET on h-BN/SiO₂ reaches a lower LFN. To further investigate the mechanism of current fluctuation, surface trap density ( ${N} _{\text {st}}$ ) is extracted. The average value of ${N} _{\text {st}}$ for Te FETs on h-BN/SiO₂ is smaller than that for Te FETs on SiO₂. It is concluded that the introduction of atomically flat h-BN dielectric decreases ${N} _{\text {st}}$ , suggesting that Te FET on h-BN/SiO₂ presents higher immunity to LFN and provides a design thought for devices with high stability in the future.