Abstract
A group III-V transistor device employing a novel layout for isolating and/or defining the active region is provided. A group III-V heterojunction is arranged over or within a substrate, and an inner drain electrode is arranged over the group III-V heterojunction. A gate has a ring shape and is arranged over the group III-V heterojunction around the inner drain electrode. An outer source electrode has a ring-shaped region arranged over the group III-V heterojunction around the gate. A method for manufacturing the group III-V transistor device is also provided.