Semiconductor device comprising metal plug having substantially convex bottom surface

摘要

A semiconductor device and method of formation are provided. The semiconductor device comprises a metal plug in a first opening over a substrate. The metal plug has a contact bottom surface that is substantially convex. The substantially convex contact bottom surface has an increased contact area as compared to a contact bottom surface of a metal plug that is not substantially convex. The increased contact area decreases a resistance of the metal plug. The increased contact area requires a smaller deposition amount to form a metal plug seed layer of the metal plug than a semiconductor device with a smaller contact area. A smaller deposition amount reduces an overhang of the deposited metal plug seed layer material. A reduced overhang of the deposited metal plug seed layer material reduces pitting in a metal plug formed from the deposited metal plug seed layer material.

主权项

1. A semiconductor device comprising:
a dielectric layer; a metal plug over a substrate, the metal plug having a contact bottom surface that is substantially convex; a metal layer in contact with sidewalls of the dielectric layer and between the dielectric layer and the metal plug; and a silicide layer between the substrate and the metal plug, wherein:
the silicide layer has a silicide layer top surface that is substantially concave to interface with the substantially convex contact bottom surface of the metal plug; andthe metal layer terminates at an edge of the silicide layer.