Semiconductor devices having reduced gate-drain capacitance

摘要

Embodiments of a semiconductor device include a semiconductor substrate having a first surface and a second surface opposed to the first surface, a trench formed in the semiconductor substrate and extending from the first surface partially through the semiconductor substrate, a gate electrode material deposited in the trench, and a void cavity in the semiconductor substrate between the gate electrode material and the second surface. A portion of the semiconductor substrate is located between the void cavity and the second surface.