A Balanced Stacked GaN MMIC Power Amplifier for 26-GHz 5G applications

This work reports the design and experimental characterization of a 4 W Ka-band MMIC power amplifier in GaN/SiC technology, featuring a balanced stacked architecture. The proposed amplifier is composed of a pair of 2-stage amplifier branches, each including a single-transistor driver stage and a 2-stacked-transistor power stage. Small-signal characterization exhibits very good agreement between measurements and simulations, while system-level characterization, employing a 50 MHz instantaneous bandwidth, 10 dB PAPR 5G FR2 signal, demonstrates the very promising linearity performance of the proposed amplifier. The measured minimum ACPR is better than -27 dBc up to an average output power of 24 dBm, from 25 GHz to 27 GHz

Electric Field and Self-Heating Effects on the Emission Time of Iron Traps in GaN HEMTs

In this paper we separately investigate the role of electric field and device self-heating (SHE) in enhancing the charge emission process from Fe-related buffer traps (0.52 eV from Ec) in AlGaN/GaN High Electron Mobility Transistors (HEMTs). The experimental analysis was performed by means of Drain Current Transient (DCT) measurements for either i) different dissipated power (PD,steady) at constant drain-to-source bias (VDS,steady) or ii) constant PD,steady at different VDS,steady. We found that i) an increase in PD,steady yields an acceleration in the thermally activated emission process, consistently with the temperature rise induced by SHE. On the other hand, ii) the field effect turned out to be negligible within the investigated voltage range, indicating the absence of Poole-Frenkel effect (PFE). A qualitative analysis based on the electric field values obtained by numerical simulations is then presented to support the interpretation and conclusions