Influence of temperature on electroless deposition of Co–P

Abstract

Electroless cobalt deposition on copper substrates using sodium hypophosphite as a reductant was investigated. The electroless plating was initiated by contact with an aluminium wire (Cu–Al galvanic cell). It was found that measurements of substrate potential are very useful for monitoring of the process. The rate of cobalt deposition was in the range of 0·7 × 10⁻³ −4·4 × 10⁻³ mg cm⁻² min⁻¹ for the temperature range of 338–358 K. The activation energy for cobalt deposition was determined to be ∼93 kJ mol⁻¹. The plating efficiency of 13–24% was estimated. Cobalt films were matt grey with many tiny pits (with diameter of 0·1 μm) on the surface.

Keywords:

• ELECTROLESS PLATING
• COBALT