Method for manufacturing semiconductor device

Abstract

A method for manufacturing semiconductor device includes the steps of providing a substrate that has a gate electrode thereon, and then forming a dielectric layer over the substrate. The dielectric layer is conformal to the profile of the substrate and has a definite thickness. Thereafter, using the gate electrode and that portion of the dielectric layer next to the sidewalls of the gate electrode as a mask, a first ion implantation is carried out. Hence, a doped drain region is formed in the substrate and a channel region is formed in the substrate just under the gate electrode. Subsequently, spacers are formed over the exposed dielectric layer next to the sidewalls of the gate electrode. Finally, using a portion of the dielectric layer next to the sidewalls of the gate electrode and the spacers as a mask, a second ion implantation is carried out. Hence, source/drain regions are formed in the substrate on each side of the gate electrode.

Dependencies are inferred from the claim text.