THE SOLUTION OF CHEMICAL PLATINUM-RHODIUM ALLOY DEPOSITION AND THE METHOD OF CONTINUOUS PLATINUM-RHODIUM ALLOY COATING FORMATION

摘要

This invention relates to chemical (autocatalytic) metal alloys deposition solutions and processes, particularly chemical deposition of platinum-rhodium alloy. The invention may be applied for the deposition of platinum-rhodium coatings on dielectrics, semiconductors, or conductors of complex configurations. This invention aims to reduce the toxicity of chemical platinum-rhodium alloy deposition solution, increase the coating formation speed, simplify and cheapen the method of continuous platinum-rhodium coating formation. According to the invention chemical platinum-rhodium alloy deposition method comprises the surface sensitisation using SnCl2 solution, activation using PdCl2 solution and immersion in a bath with a chemical deposition solution comprising 0.003 to 0.03 M K2PtCl as a platinum (IV) ion source, 0.001 - 0.005M RhCl3 as a rhodium (III) ion source, 0.015 to 0.25 M diisopropanolamine (Dipa), 0.01 to 0.1 M N2H4 and concentrated acetic acid CH3COOH as pH adjuster to the mixture pH 11.5.