Influence of Bath Formulations on Low-Temperature Electroless Deposition of Ni-P Alloys
Chulaluk Somphotch , Ekasit Nisarattanaporna, Yuttanant Boonyongmaneeratb,** Author for corresponding; e-mail address: yuttanant.b@chula.ac.th
Volume: Vol.41 No.5/2 (OCTOBER 2014)
Research Article
DOI:
Received: 4 April 2013, Revised: -, Accepted: 26 July 2013, Published: -
Citation: Somphotch C., Nisarattanaporna E. and Boonyongmaneeratb Y., Influence of Bath Formulations on Low-Temperature Electroless Deposition of Ni-P Alloys, Chiang Mai Journal of Science, 2014; 41(5/2): 1332-1340.
Abstract
The influence of the concentrations of a metal source, a reducing agent, and hydrogen ions on the electroless deposition of Ni-P alloys is investigated at a relatively low deposition temperature of 65oC. Hypophosphite and pH are determined to be the main controllers of the deposition rate. Decent bath stability and a fair deposition rate of ~20 μm/hr, comparable to that obtained under the typical deposition temperature of ~85oC, are achievable by maintaining the nickel sulfate/sodium hypophosphite concentration ratio at ~0.4. A moderately high sodium hypophosphite concentration of 0.38 M and a high pH of 9 and above are required. The empirical kinetics equations of the electroless nickel deposition are discussed and developed.