Low-frequency noise characterization of positive bias stress effect on the spatial distribution of trap in β-Ga2O3 FinFET

Abstract

The reliability of a β-Ga2O3 thin-film field-effect transistor is investigated under positive-bias stress (PBS). The transistor has a tri-gate structure with a gate dielectric of Al2O3. By characterizing low-frequency noise (LFN), the spatial distribution of trap in the gate dielectric was quantitatively extracted. The measured power spectral density (PSD) followed a 1/f-shape due to trapping and de-trapping of the channel carriers to and from the gate dielectric. Notably, the vertical distribution of the traps perpendicular to the interface of β-Ga2O3 and Al2O3 was mapped