Metal-oxide field effect transistor having an oxide region within a lightly doped drain region

Abstract

A semiconductor device and a method for manufacturing the same are provided. A semiconductor device includes a semiconductor substrate and a gate structure formed on the semiconductor substrate. A source region and a drain region are disposed on opposite sides of the gate structure on the semiconductor substrate. A lightly-doped drain region is adjacent to a side of the drain region close to the gate structure, and a lightly-doped source region is adjacent to a side of the source region close to the gate structure. An oxidation region is disposed in the lightly-doped drain region. A trench extends from the surface of the semiconductor substrate to the drain region. A source electrode is disposed on the source region, and the drain electrode has a first portion disposed on the drain region and a second portion disposed in the trench.