abstract |
An electroplating apparatus prevents anode-mediated degradation of electrolyte additives by creating a mechanism for maintaining separate anolyte and catholyte and preventing mixing thereof within a plating chamber. The separation is accomplished by interposing a porous chemical transport barrier between the anode and cathode. The transport barrier limits the chemical transport (via diffusion and/or convection) of all species but allows migration of ionic species (and hence passage of current) during application of sufficiently large electric fields within electrolyte. |