Design and fabrication of high-k filled sub-100 nm gap resonators with embedded dielectric field effect transistor for ultra high frequency applications

A novel fabrication process for the integration of Field Effect Transistors in electrostatically actuated bulk acoustic resonators is demonstrated. ALD-deposited HfO
2
is used as a high-k dielectric for the FET and as an etch-stop layer during the release of the resonator structure as well, enabling the creation of sub-100 nm air-gap resonators with FET amplification enhancement.