Comprehensive analysis and investigation of GaN LNA for 3–4 GHz using different gate-drain spacing

Abstract

This work investigates the impact of the device technological parameter - gate-drain access region spacing ($L_{\mathrm{GD}}$) - for GaN High Electron Mobility Transistors (HEMTs), on the design of low noise amplifiers (LNAs) for the 3–4 GHz range. We compare two GaN LNA variants, characterized by $L_{\mathrm{GD}}$ values of $0.875\mu m$ and $1\mu m$, to highlight the significance of gate-drain spacings in determining performance metrics. This study contributes insights into the effect of gate-drain spacing on the GaN LNAs, and evaluates the RF characteristics, Noise Fig. (NF), and power metrics for different $L_{\mathrm{GD}}$ values. Based on our findings, we assert that the $0.875\mu m{L}_{\mathrm{GD}}$ LNA exhibits superior performance over its counterpart in the evaluated benchmarks, along with the physical reasoning.