Middle-of-line interconnect having low metal-to-metal interface resistance
AssigneeInternational Business Machines Corporation
InventorsAlex Joseph Varghese, Richard A. Conti, Su Chen Fan
Life of this patent
Estimating the term…
Abstract
Provided are embodiments for an MOL interconnect structure having low metal-to-metal interface resistance interconnect structure including one or more contacts of one or more devices formed on a substrate. A dielectric layer is formed on one or more devices. One or more trenches are formed in the dielectric layer. The MOL interconnect structure also includes a barrier layer formed on one or more portions of the dielectric layer, along with a metallization layer, wherein the metallization layer forms a metal-to-metal interface with the one or more contacts.
Claims10
A method of fabricating an interconnect structure, the method comprising:
- forming a dielectric layer over one or more contacts of one or more devices;
- forming a trench in the dielectric layer over one or more contacts;
- depositing a barrier layer on the dielectric layer, the trench, and the one or more contacts;
- forming a cap layer on one or more portions of the barrier layer, wherein forming the cap layer comprises depositing the cap layer on one or more portions of the barrier layer outside the trench to expose one or more portions of the barrier layer disposed in the trench, wherein a bottom-most portion of the trench and one or more portions of sidewalls of the trench remain exposed while forming the cap layer, wherein forming the cap layer is performed by a plasma vapor deposition (PVD) Si deposition process;
- removing the one or more portions of the barrier layer disposed in the trench;
- removing the cap layer from the one or more portions of the barrier layer outside the trench;
- and
- depositing a metal interconnect layer directly on the one or more contacts to form a metal-to-metal interface between the metal interconnect layer and the one or more contacts, wherein the metal interconnect layer directly contacts the one or more contacts, wherein depositing the metal interconnect layer is formed in a single metal deposition process.
A method of fabricating an interconnect structure, the method comprising:
- forming a dielectric layer over one or more contacts of one or more devices;
- forming a trench in the dielectric layer over one or more contacts;
- depositing a harrier layer on the dielectric layer, the trench, and the one or more contacts;
- forming a cap layer on one or more portions of the harrier layer, wherein forming the cap layer comprises depositing the cap layer on one or more portions of the barrier layer outside the trench to expose one or more portions of the barrier layer disposed in the trench, wherein a bottom-most portion of the trench and one or more portions of sidewalls of the trench remain exposed while forming the cap layer;
- removing the one or more portions of the barrier layer disposed in the trench;
- removing the cap layer from the one or more portions of the barrier layer outside the trench;
- and
- depositing a metal interconnect layer directly on the one or more contacts to foam metal-to-metal interface between the metal interconnect layer and the one or more contacts, wherein the metal interconnect layer directly contacts the one or more contacts, wherein depositing the metal interconnect layer is formed in a single metal deposition process.
Dependencies are inferred from the claim text.