GaN HEMT Current-Gain Peak: An Insight into the Effects of the Bias Condition

The current-gain peak (CGP) appearing in the frequency-dependent behaviour of the magnitude of the short-circuit current-gain (h
21
) is, currently, attracting much attention. Recently, a systematic procedure has been proposed for accomplishing a straightforward fitting of h
21
using the complex Lorentzian function and, then, an effective identification of a set of parameters for an accurate and complete assessment of the size and shape of CGP. The attention has been focused on the study of CGP versus ambient temperature and drain-source voltage (V
DS
) by considering a gallium nitride (GaN) high electron-mobility transistor (HEMT) as device under test (DUT). This contribution is aimed at providing a further insight into the analysis of CGP by applying the developed procedure for investigating the impact of the gate-source voltage on the size and shape of CGP.