RF performance of pre-patterned locally-embedded-back-gate graphene device

We measured Radio-Frequency (RF) performance of devices with graphene grown using low temperature Inductively-Coupled Plasma Chemical Vapor Deposition (ICP-CVD) method on 6-inch wafer for the first time. To remove the coupling of electrode in-plane, we introduced locally-embedded-back-gate using TiN metal. The symmetric structure of 2-gate fingers was adopted to reduce misalign issue during fabrication of the structure with underlap between Gate and Source/Drain, which was also adopted for the reduction of parasitic capacitance due to gate oxide with high dielectric constant. Cutoff frequency (f_T) increase is moderately obtained with the decrease of gate length. Despite the low g_m due to underlap region, we obtained f_T =80 GHz.