Noise characterisation of GaN current aperture vertical electron transistor metal‐insulated semiconductor field effect transistor with Δ‐shaped gate for low noise radio frequency amplifiers

Abstract

In this article, vertical CAVET with boron-doped GaN layer as current blocking layer (CBL) for AlGaN/GaN is proposed in this study, and different electrical characteristics of the devices, such as DC (I ds À V ds ), small-signal radio frequency and high-frequency microwave noise performances, are characterised using Synopsys TCAD simulations. The vertical CAVET AlGaN/GaN metal-insulated semiconductor field effect transistor (MIS-HEMT) has been found to have a high threshold V T = 6.36 V, drain saturation current, I ds,sat = 3.41 kA/cm 2 , reduced OFF-state current <10 À12 and improved high frequency and noise performances. The findings provide insight on noise sources and provide information on how to improve GaN transistor noise performance. Its useful characterisation tool for learning more about the imperfections in advanced AlGaN/GaN MIS-HEMTs and how they evolve. A twoport noise equivalent-circuit description is used to calculate data for noise.Using data from noise and scattering parameters that have been measured, we evaluated the effect of noise sources due to gate and drain, as well as their correlation. The devices exhibit a minimum noise figure (NF min ) and an equivalent noise resistance (R n ) of 1.21 dB and 20 Ω at 20 GHz, with V gs = 5 V and V ds = 10 V, which is small and appropriate for low-noise amplifiers with a wide bandwidth. The maximum output power density P out of 23 dBm and the maximum PAE of 63.3% are achieved for GaN V-shaped CAVET MIS-HEMTs with V ds = 10 V at 3.12 GHz is achieved. A comparison is made between the noise performance of conventional HEMTs, MIS-HEMTs and FETs. The methods for obtaining the noise figure (NF min ) and other noise metrics are then explained and compared with those found in the literature.