Patent ID: 8278721

Claim:
A method for forming a contact plug, comprising: forming a gate, a sidewall spacer, a sacrificial sidewall spacer, a source region and a drain region on a substrate, wherein the sidewall spacer is formed around the gate, the sacrificial sidewall spacer is formed to cover the sidewall spacer, and the source region and the drain region are formed within the substrate and on respective sides of the gate; forming an interlayer dielectric layer, with the gate, the sidewall spacer and the sacrificial sidewall spacer being exposed; removing the sacrificial sidewall spacer to form a contact space, wherein the sacrificial sidewall spacer is made of a material that is different from any of materials that the gate, the sidewall spacer and the interlayer dielectric layer are made of; forming a conducting layer to fill the contact space; and cutting off the conducting layer to form at least two conductors connected to the source region and the drain region, respectively.