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This paper describes a novel high-tone bulk acoustic resonator (HBAR) integrated with a surface micromachined FBAR (film bulk acoustic resonator) filter on sapphire substrate. The single-mode HBAR exhibited a loaded quality factor (Qloaded) of 3,580 at 2.5 GHz with a total size (including the contact pads) of 0.8×0.4×0.4mm3. The integrated narrow band FBAR filter provides adequate suppression (>4dB) of the unwanted modes in the HBAR. This high Q and small size resonator is ideally suited for Pierce oscillator for voltage controlled oscillator (VCO) above 2 GHz.