III-Nitride Transistor With A Cap Layer For RF Operation

Abstract

This disclosure describes the structure of a transistor that provides improved performance by reducing the off-state capacitance between the source and the drain by using a cap layer to extend the electrical distance between the gate and the source and drain contacts. In certain embodiments, a dielectric layer may be disposed between the gate electrode and the cap layer and vias are created in the dielectric layer to allow the gate electrode to contact the cap layer at select locations. In some embodiments, the gate electrode is offset from the cap layer to allow a more narrow cap layer and to allow additional space between the gate electrode and the drain contact facilitating the inclusion of a field plate. The gate electrode may be configured to only contact a portion of the cap layer.

Dependencies are inferred from the claim text.