Improvement in high frequency and noise characteristics of InP-based HEMTs by reducing parasitic capacitance

We improved the high frequency and noise characteristics of InP-based high electron mobility transistors (HEMTs) by reducing parasitic capacitance in the gate region and achieved a cutoff frequency (f_T) of 517 GHz and minimum noise figure (NF_min) of 0.71 dB at 94 GHz even after the interconnection process. Scaling of the gate-recess length is effective for enhancing transconductance (g_m). Furthermore, the cavity structure successfully reduced the parasitic capacitance originating from interlayer dielectric films.