METHOD OF IMPROVED CA/CB CONTACT AND DEVICE THEREOF

摘要

Processes for forming merged CA/CB constructs and the resulting devices are disclosed. Embodiments include providing a replacement metal gate (RMG) between first and second sidewall spacers surrounded by an insulator on a substrate, the RMG having a dielectric layer directly on the first and second sidewall spacers and having metal on the dielectric layer; providing an oxide layer over the insulator, the first and second sidewall spacers, and the RMG; forming a source/drain contact hole through the oxide layer and the insulator, adjacent to the first sidewall spacer; forming a gate contact hole through the oxide layer over the source/drain contact hole and extending to the metal of the RMG; enlarging the source/drain contact hole to the metal of the RMG; and filling the enlarged source/drain contact hole and gate contact hole with metal.

主权项

1. A method comprising:
providing a replacement metal gate (RMG) between first and second sidewall spacers, the RMG and the first and second sidewall spacers surrounded by an insulator on a substrate, wherein the RMG comprises a dielectric layer having an inner side and an outer side, and a metal layer and the outer side of the dielectric layer directly abuts the first and second sidewall spacers and the metal layer directly contacts the inner side of the dielectric layer; providing an oxide layer over the insulator, the first and second sidewall spacers, and the RMG; forming a source/drain contact hole through the oxide layer and the insulator, adjacent to, but not contacting, the first sidewall spacer, leaving a sliver portion of the insulator between the source/drain contact hole and the first sidewall spacer; forming a gate contact hole through the oxide layer over the source/drain contact hole and extending to the metal layer at an upper surface of the RMG, while concurrently removing the sliver portion of the insulator; enlarging the source/drain contact hole to the metal layer of the RMG by removing the first sidewall spacer and a portion of the dielectric layer between the first sidewall spacer and the metal layer; and filling the enlarged source/drain contact hole and gate contact hole with a contact metal.