Growth Mechanism of Copper Whiskers by Hydrogen Reduction of Cuprous Iodide

Abstract

A study has been made of the growth of copper whiskers by hydrogen reduction of cuprous iodide. Alternative mechanisms have been proposed involving, respectively, vapor phase reduction and reduction at the whisker tip. A necessary consequence of the vapor phase reduction mechanism is the presence of a highly supersaturated copper vapor. It is shown that the vapor phase is not highly supersaturated in copper vapor and that reduction must occur heterogeneously. It is further shown that the reduction process occurs only at the tip and is most simply accounted for by assuming reduction at the step associated with an axial dislocation.