Title :
Contact and via structures with copper interconnects fabricated using dual Damascene technology
Author :
Lakshminarayanan, S. ; Steigerwald, J. ; Price, D.T. ; Bourgeois, M. ; Chow, T.P. ; Gutmann, R.J. ; Murarka, S.P.
Author_Institution :
Center for Integrated Electron., Rensselaer Polytech. Inst., Troy, NY, USA
Abstract :
A novel submicron process sequence was developed for the fabrication of CoSi/sub 2//n/sup +/-Si, CoSi/sub 2//p/sup +/-Si ohmic contacts and multilevel interconnects with copper as the interconnect/via metal and titanium as the diffusion barrier. SiO/sub 2/ deposited by plasma enhanced chemical vapor deposition (PECVD) using TEOS/O/sub 2/ was planarized by the novel technique of chemical-mechanical polishing (CMP) and served as the dielectric. The recessed copper interconnects in the oxide were formed by chemical-mechanical polishing. (dual Damascene process). Electrical characterization of the ohmic contacts yielded contact resistivity values of 10/sup -6//spl Omega/-cm/sup 2/ or less. A specific contact resistivity value of 1.5/spl times/10/sup -8//spl Omega/-cm/sup 2/ was measured for metal/metal contacts.<>
Keywords :
cobalt compounds; copper; elemental semiconductors; integrated circuit technology; metallisation; ohmic contacts; semiconductor-metal boundaries; silicon; silicon compounds; CoSi/sub 2/-Si; CoSi/sub 2//n/sup +/-Si; CoSi/sub 2//p/sup +/-Si; Cu; Cu interconnects; PECVD; SiO/sub 2/; TEOS/O/sub 2/; Ti; Ti diffusion barrier; chemical vapor deposition; chemical-mechanical polishing; dual Damascene process; electrical characterization; fabrication; multilevel interconnects; ohmic contacts; planarisation; plasma enhanced CVD; recessed Cu interconnects; Chemical processes; Chemical vapor deposition; Conductivity; Copper; Dielectrics; Fabrication; Ohmic contacts; Planarization; Plasma chemistry; Titanium;
Journal_Title :
Electron Device Letters, IEEE
