Study of microwave damage effect on HEMT low noise amplifier under different drain voltage bias

Abstract

The microwave damage effect on high electron mobility transistor (HEMT) low noise amplifier (LNA) under different drain voltage bias is studied using TCAD simulation and experiments. Simulation and experimental results suggest that the damage power thresholds and damage locations of single stage LNA under different drain voltage bias are almost the same. Nevertheless, the output power under zero drain bias is about 5.6dB higher than it under normal (3V) drain bias with the injection of large power microwave pulses. In Addition, the output power relative to it under normal drain bias decreases linearly with the increase of drain bias, following the function of PdB=−1.85Vds+5.7. For multi-stage LNA, the observation using optical microscope reveals that the first and second stage HEMT of LNA under zero drain bias are both damaged while only first stage HEMT of LNA under normal bias is damaged with the injection of same large power microwave pulses, which is consistent with simulated output characteristics results.