Dimensional metrology challenges for ULSI interconnects

Low-Temperature Deposition of Conformal Copper Films in Supercritical CO2 by Catalytic Hydrogen Reduction of Copper Hexafluoroacetylacetonate

“…Recently, copper is used as an interconnecting material for microelectronic devices because of its lower resistivity and higher reliability in performance compared with the conventional aluminum interconnect. Since copper interconnect is difficult to fabricate using a subtractive etch process, which is widely used for aluminum interconnect, due to difficulty in plasma etch, the copper patterning would be achieved by the so-called “damascene process” . In the damascene process, copper is deposited in holes and trenches patterned in dielectric films such as silicon dioxide followed by removal of the superfluous copper film with a chemical mechanical polishing process.…”