Submicron pseudomorphic Al0.2 Ga0.8As/In0.25Ga0.75 As-HFET made by conventional optical lithography for microwave circuit applications above 100GHz

In this work the device performance of a submicrometer pseudomorphic FET made by conventional optical lithography using a single-layer photoresist will be presented. With this technique a gate-length of 0.6μm can be reproducible achieved. Using a multiple finger structure with air-bridge technology a maximum taransconductance of 47OmS/mm and a cutoff-frequency of 111GHz was obtained.