Environmentally friendly processes in the manufacture of Saturn solar cells

The current metallisation process for the manufacture of laser grooved, buried grid solar cells is based on electroless chemical plating. An electrolytic copper plating process is described that has the advantages of increased bath lifetime; shorter processing time; improved material usage; reduced over-plating; superior quality of the copper deposited and reduced effluent treatment costs. This paper describes work using a prototype electro-plating bath. This paper also describes an investigation of the use of cyanide-free solutions for coating the plated copper deposit on the solar cell. A number of electroless silver and tin coatings offer environment-friendly alternatives to the current silver cyanide process.