Dual damascene interconnect structures having different materials for line and via conductors

US6958540B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Jeffrey P. Gambino · Gresham, US
• Edward C. Cooney, III · Jericho, US
• Anthony K. Stamper · Williston, US
• William T. Motsiff · South Burlington, US
• Michael Lane · Somers, US
• Andrew H. Simon · Fishkill, US

Key dates

• Filing date: Jun 23, 2003
• Grant date: Oct 25, 2005
• Expiry date: Jun 23, 2023

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2924/0002
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

Interconnect structures are disclosed for forming dual damascene back-end-of-line (BEOL) structure using materials for the vias or studs which are different from those used for the line conductors, or using materials for the via liner which are different from those used for the trench liner, or having a via liner thickness different from that of the trench liner. Preferably, a thick refractory metal is used in the vias for improved mechanical strength while using only a thin refractory metal in the trenches to provide low resistance.