DC and RF characteristics optimization of AlGaN/GaN/BGaN/GaN/Si HEMT for microwave-power and high temperature application

Abstract

AlGaN/GaN/Si high electron mobility transistors (HEMTs) developed by molecular beam epitaxy (MBE) are studied with several methods for characterization, the most utilized are direct-current and radio-frequency measurements, to see power and microwave performance of components. The increase in these parameters is not based just with on improvement technological for example, decrease of length gate (Lg) and passivation. For sure, another very important point is to reduce the thickness of barrier while keeping the reduction in the length of gate, in order to reduce the transit time (τ), and consequently access to highest cut-off frequency (FT). For this situation, it’s appears a harmful phenomenon of type “punch-through”, because of the weak confinement of electrons in the channel. In this paper, the main objective is to show how to reduce this effect. Keywords: HEMT GaN, Current-voltage characteristics, RF characteristics, Alloys BGaN, Radio-frequency