A study of the effect of post-metal etch wet cleaning processes and silicon oxynitride film on charge induced corrosion of tungsten vias

• Published in: Materials science in semiconductor processing 2010-12, Vol.13 (5), p.315-319
• Main Authors: Lee, Szetsen, Ni, Chi-Jung
• Format: Article
• Language: English
• Subjects: Applied sciences; Charge; Charge-induced corrosion; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Corrosion; Corrosion mechanisms; Corrosion tests; Cross-disciplinary physics: materials science; rheology; Dielectric thin films; Dielectrics, piezoelectrics, and ferroelectrics and their properties; End point; Etching (metallography); Exact sciences and technology; Materials science; Metals. Metallurgy; Other materials; Physics; Semiconductors; Shielding; Silicon oxynitride; Specific materials; Tungsten; Tungsten via
• ISSN: 1369-8001; 1873-4081
• DOI: 10.1016/j.mssp.2011.02.011

We report the experimental study of prevention of charge induced corrosion of tungsten vias after metal etch using wet chemical solutions and silicon oxynitride (SiON) shielding film. It was found that one of the solutions could effectively prevent corrosion of tungsten vias and leave essentially no polymer residue on metal lines. The performance of other solutions is poor due to the formation of polymer residues or sidewall erosion on metal lines. We have demonstrated that the combination of wet chemical treatment with SiON as the dielectric charge shielding film was as effective as other standard methods for preventing corrosion of tungsten vias. It was also found that SiON has strong impacts on chamber wall conditions and metal line profile.