Electromigration  Go To Index Energy dispersive X-ray spectr ...  

    Electrophoresis

    Phenomenon, where colloid particles dispersed in a solution move to a live electrode. In colloidal solutions of Au, Sg, S, sulfides, SiO2 etc. the particles move away from the direction of the electric field whereas aluminum hydroxide and iron hydroxide follow the direction of the field. If brighteners are added to the electrolyte solution during the electrodeposition, these will settle on higher solder layers by electrophoresis while more metal is deposited at the deeper sites. After coating, the brightener is removed with a brush, leaving a uniformly thick metal layer. By adding hard tungsten carbide powder (WC) to the electrolyte solution, a metal layer containing tungsten carbide can be produced by electrophoresis. Sometimes the migration of solder joints is confused with the phenomenon of electrophoresis. See also Electromigration.