Describe is a resonator that uses anti-ferroelectric (AFE) materials in the gate of a transistor as a dielectric. The use of AFE increases the strain/stress generated in the gate of the FinFET. Along with the usual capacitive drive, which is boosted with the increased polarization, additional current drive is also achieved from the piezoelectric response generated to due to AFE material. In some embodiments, the acoustic mode of the resonator is isolated using phononic gratings all around the resonator using the metal line above and vias' to body and dummy fins on the side. As such, a Bragg reflector is formed above or below the AFE based transistor. Increased drive signal from the AFE results in larger output signal and larger bandwidth.