A Systematic and Numerical Methodology for GaN HEMT Current-Gain Peak Analysis Using the Complex Lorentzian Function

The purpose of this letter is to present a measurement-based analysis of the transistor current-gain peak (CGP), which consists of a sudden peak in the magnitude of the short-circuit current-gain (
$h_{21}$
) at a certain frequency. A systematic and numerical approach is proposed to analyze CGP. This powerful and technology-independent methodology is based on developing an accurate fitting of the experiments using the complex Lorentzian function, thus allowing an accurate and straightforward extraction of the parameters describing CGP. The validity of the developed technique is fully demonstrated by its application to the analysis of CGP for a gallium nitride (GaN) high-electron-mobility transistor (HEMT) at different ambient temperatures and bias conditions.