GaN-based HFET Design for Ultra-high frequency Operation

In this paper, a new approach is proposed for optimizing the design of GaN-based HFETs for ultra high frequency operation. The key features of the ultra high frequency design include recessed gate MOSHFET .This approach is based on our analytical model that accounts for the electric field and potential distribution outside the gated region. It is concluded that, GaN HFETs should be able to reach ultrahigh frequency performance at least comparable to that of InGaAs based HFET but at a much higher power levels. However, this will require new designs with quaternary buffers, very high electron sheet density in the gate-to-drain spacing, and precise gate-to-drain distance control.