Failure mechanisms of GaN HEMTs for microwave and millimeter-wave applications: From interdiffusion effects to hot-electrons degradation

Gallium Nitride High Electron Mobility Transistor are the most prominent devices for application to high power density, high efficiency transmission system in the microwave and millimeter-wave frequency range. High bandwidth requirements of 5G and future telecommunication infrastructure require the adoption of higher frequency bands beyond 60 GHz, thus accelerating the scaling of devices gate lengths below 150 nm, possibly promoting failure mechanisms accelerated by electric field and hot-electron effects. This paper reviews main failure modes and mechanisms of GaN HEMTs for microwave and millimeter-wave applications11Work partially supported by EUGANIC project (EDA Contract B 1447 IAP1 GP), EC Horizon 2020 ECSEL project SG_GaN_2, ESA ESTEC project RELGAN, Italian MIUR PRIN project GANAPP, by the Office of Naval Research award N00014-20-1-2177, under the supervision of Paul Maki