Alkaline free electroless deposition

摘要

Alkali-free layers of pure metals such as copper, nickel and cobalt were deposited on noble metal or noble metal sensitized substrates by electroless deposition using pure quaternary ammonium hydroxides or quaternary phosphonium hydroxides to generate the hydroxyl ion (OH-) needed to produce electrons for the metal reduction. Using the new alkaline-free electroless compositions, uniform, continuous and reproducible metal layers were selectively deposited with excellent electrical properties. With the improved compositions and process, nanosize copper lines having widths in the range of 100 to 500 nm were prepared.