Integration of a low permittivity spin-on embedded hardmask for Cu/SiLK resin dual damascene

The feasibility of integrating a low permittivity spin-on hardmask (SoHM) into a Cu dual damascene structure using SiLK* Semiconductor Resin (*trademark of The Dow Chemical Company) has been investigated. The study focussed on the replacement of the embedded etch stop deposited by chemical vapor deposition (CVD) by a low permittivity inorganic film deposited by traditional spin coating. The evaluation was performed using an existing damascene test vehicle. The etch selectivity was evaluated by applying different SoHM thicknesses and etch times. The patterning chemistry used was O/sub 2//N/sub 2/ based, in a high density TCP etch tool. The electrical data collected indicated no significant yield difference when using an embedded SoHM. The integrated k value of the SoHM film is 3.2, as compared to /spl sim/4.0 for SiO/sub 2/ films.