SEMICONDUCTOR DEVICE WITH REDUCED MILLER CAPACITANCE AND FABRICATION METHOD THEREOF

摘要

A semiconductor transistor device includes an epitaxial layer grown on a semiconductor substrate; an ion well with a junction depth in the epitaxial layer; a gate trench with a depth shallower than the junction depth in the ion well; a recess at the bottom of the gate trench; a gate oxide layer at surface of the gate trench and in the recess to form a protruding tip structure; a gate in the gate trench; and a drain extension region between the gate trench and the epitaxial layer.