Evolution of metal plating for silicon solar cell metallisation

ABSTRACT Increasing silver prices and reducing silicon wafer thicknesses provide incentives for silicon solar cell manufacturing to develop new metallisation strategies that do not rely on screen printing and preferably reduce silver usage. Recently, metal plating has re‐emerged as a metallisation process that may address these future requirements. This paper reports on the evolution of metal plating techniques, from their use in early silicon solar cells, to current light‐induced plating processes. Unlike screen‐printed metallisation, metal plating typically requires an initial patterning step to create openings in a masking layer for the subsequent self‐aligned metallisation. Consequently, relevant recently‐developed dielectric patterning methods are also reviewed because, in many cases, the plating process must be adapted to the properties of the patterning method used. The potential of new light‐induced plating processes to form cost‐effective copper metallisation is supported by the recent activity in the development of metal plating tools for commercial silicon solar cell manufacture. Copyright © 2012 John Wiley & Sons, Ltd.