Reactivating and recoating of nickel or nickel:phosphorus layers - by immersion in hypophosphite soln. followed by chemical or electrolytic coating, esp. in mfg. thin film resistors

摘要

The layer (I) of Ni or Ni-P is produced by electroless- or electro-plating, and has a passivated surface. Layer (I) is treated in a soln. (B1) contg. hypophosphite, and is then given a coating (II) via a chemical or electroplating bath (B2). Soln. (B1) is pref. heated to max. 100 degrees C and used to decompose the passivated surface catalytically thus reactivating the surface of layer (I). After reactivation, layer (I) is pref. immersed immediately in bath (B2), which is pref. the bath employed initially to obtain layer (I), or another bath, esp. an electroplating bath. Used pref. in the mfr. of Ni-P thin film resistors, where a layer (I) of Ni-P can be locally increased in thickness to reduce its surface resistivity. The invention can also be used in depositing Cu onto Ni-P to make conductor paths; or for the repair of films.