Properties of electroless cobalt films

Cobalt films, with a small weight percentage of phosphorus, have been made by electroless deposition from hypophosphite baths. A wide variation of their magnetic properties, and in particular coercivity, has been observed. Observations of these films by transmission electron microscopy have demonstrated their particle nature. Attempts are made to correlate the observed coercivity with crystallite (or particle) size, and it is shown that although the crystallite size is of great importance, it is not necessarily the only factor determining the coercivity.