The invention relates to a
semiconductor structure and a formation method thereof. The formation method includes the following steps that: a substrate is provided, gate structures are arranged on thesubstrate, source-drain
doping regions located at two sides of each gate structure are formed in the substrate, an interlayer
dielectric layer is formed on the substrate which is not covered by the gate structure, and the interlayer
dielectric layer covers the tops of the gate structures; first contact openings exposing the source / drain
doping regions are formed in the interlayer
dielectric layerat two sides of each gate structure; second contact openings which pass through the interlayer
dielectric layer above the gate structures are formed; after the second contact openings are formed, pre-amorphization implantation is performed on the source / drain
doping regions; after the pre-amorphization implantation process,
metal silicide layers are formed at the bottoms of the first contact openings; and after the
metal silicide layers are formed, first
contact hole plugs are formed in the first contact openings, and second
contact hole plugs are formed in the second contact openings. With the formation method of the present invention adopted, amorphous
layers formed at the bottoms of the first contact openings can be prevented from being oxidized during the formation of the second contact openings, and therefore, the problem that the
metal silicide layers are difficult to form can be avoided.