Protruding contact for integrated chip

摘要

The present disclosure relates to a method of forming a back-end-of-the-line metal contact that eliminates RC opens caused by metal dishing during chemical mechanical polishing. The method is performed by depositing a sacrificial UV/thermal decomposition layer (UTDL) above an inter-level dielectric (ILD) layer. A metal contact is formed that extend through the ILD layer and the sacrificial UTDL. A chemical mechanical polishing (CMP) process is performed to generate a planar surface comprising the sacrificial UTDL. The sacrificial UTDL is then removed through an ultraviolet exposure or a thermal anneal, so that the metal contact protrudes from the ILD layer.

主权项

1. An integrated chip, comprising:
a metal contact vertically extending through a first inter-level dielectric (ILD) layer and protruding outward from a top surface of the first ILD layer, wherein the metal contact has an upper surface with outer edges arranged over the top surface; a second ILD layer overlying the first ILD layer; and a metal wire disposed within the second ILD layer over the metal contact, wherein a surface of the metal wire facing the metal contact comprises a first recess having sidewalls connecting a lower surface of the metal wire to an interior surface of the first recess over the metal contact.