A mechanism for electroless Cu plating onto Si

✍ Scribed by Sebastião G. dos Santos Filho; AndréA. Pasa; Claus M. Hasenack

• Book ID: 104306205
• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 363 KB
• Volume: 33
• Category: Article
• ISSN: 0167-9317
• DOI: 10.1016/s0167-9317(96)00040-8

✦ Synopsis

In this work the electrochemical mechanism of copper plating on silicon during immersion into diluted hydrofluoric acid (D-HF) solutions is investigated. For that purpose, silicon wafers were immersed for various time intervals into D-HF intentionally contaminated with copper from copper sulphate. The RBS analysis of the plated films revealed the presence of oxygen at the copper-silicon interface. It was found that concomitantly to the copper film deposition silicon consumption occurred at a ratio of l: 1 (one consumed silicon atom for one plated copper ion) instead of the ratio of 1:2 usually accepted for silicon dissolution in presence of fluoride ions. In conclusion, a new electrochemical copper plating mechanism is proposed.

(3) From these equations, it is inferred that for each two atoms of copper which plate onto the silicon *Corresponding author.