Title :
Air-gaps in 0.3 μm electrical interconnections
Author :
Kohl, Paul A. ; Bhusari, Dhananjay M. ; Wedlake, Michael ; Case, Carlye ; Klemens, Fred P. ; Miner, John ; Lee, Byung-Chan ; Gutmann, Ronald J. ; Shick, Robert
Author_Institution :
Sch. of Chem. Eng., Georgia Inst. of Technol., Atlanta, GA, USA
Abstract :
A copper/air-gap interconnection structure using a sacrificial polymer and SiO/sub 2/ in a damascene process has been demonstrated. The air-gap occupies the entire intralevel volume with fully densified SiO/sub 2/ as the planar interlevel dielectric. The copper was deposited by physical vapor deposition and planarized by chemical-mechanical planarization. The Ta/Cu barrier/seed layer was deposited by physical vapor deposition; the bulk copper was electrochemically deposited. The resulting structure has an effective intralevel dielectric constant of 2.19.
Keywords :
chemical mechanical polishing; copper; integrated circuit interconnections; ion beam assisted deposition; permittivity; 0.3 /spl mu/m electrical interconnections; 0.3 mum; Cu; Cu/air-gap interconnection structure; Ta/Cu barrier/seed layer; air-gaps; chemical-mechanical planarization; damascene process; effective intralevel dielectric constant; fully densified SiO/sub 2/; intralevel volume; physical vapor deposition; planar interlevel dielectric; Air gaps; Chemical vapor deposition; Copper; Dielectric constant; Dielectric materials; Etching; Inorganic materials; Integrated circuit interconnections; Planarization; Polymers;
Journal_Title :
Electron Device Letters, IEEE
