| || Preparation and Optimization of Pyrophosphate Bath for Copper Electroplating of Microwave Components
Author : Bhatgadde, L.G.;Mahapatra, S.
Source : Defence Science Journal ; Vol:38(2) ; 1988 ; pp 119-123
Subject : 544.6 Electrochemistry
Keywords : Copper deposition;Pyrophosphate electrolytes;Copper pyrophosphate;Plating bath
Abstract : The principles of copper deposition from pyrophosphate electrolyte have been explained. Based on these principles, a method of preparation of plating bath from basic constituents has been described. It was found that copper pyrophosphate is precipitated from solutions of copper sulphate and potassium pyrophosphate at a pH of 5.0. For maximum efficiency, copper pyrophosphate has to be dissolved in potassium pyrophosphate in a weight ratio of 1:4 or a total P/sub 2/O/sub 7/ : Cu ratio of 7.5 :1. By using optimum values of anode : cathode area, 2.5, pH, 5.0, temperature, 55 degree C and a cathode current density of 0.8 A/dm/sup 2/, bright, adherent copper electroplates were deposited on electroless copper plated Al/sub 2/O/sub 3/ substrates employed in microwave components.