Techniques are provided for hybrid bonding metallic bonding pads embedded in high-K dielectric material to form a high capacitance device. For example, a device comprises a first semiconductor structure bonded to a second semiconductor structure, and a plurality of metal pads at an interface portion between the first semiconductor structure and the second semiconductor structure. The plurality of metal pads are disposed in a high-K dielectric layer. The plurality of metal pads and the high-K dielectric layer comprise at least one capacitor.

The present disclosure relates to semiconductor structures and, more particularly, to a stacked high-power radio frequency (RF) switch and methods of manufacture. The structure includes: a top substrate having at least one top transistor and metal wiring structures; and a bottom substrate having at least one bottom transistor and metal wiring structure. The bottom substrate is attached to the top substrate with the at least one top transistor being electrically connected to the at least one bottom transistor. A portion of the metal wiring structures of the top substrate and a portion of the metal wiring structures of the bottom substrate being at least one shared capacitor between the at least one top transistor and the at least one bottom transistor. Airgaps may be formed above the transistor.