In a solar cell having p doped regions and n doped regions alternately
formed in a surface of a semiconductor wafer in offset levels through use
of masking and etching techniques, metal contacts are made to the p
regions and n regions by first forming a base layer contacting the p
doped regions and n doped regions which functions as an antireflection
layer, and then forming a barrier layer, such as titanium tungsten or
chromium, and a conductive layer such as copper over the barrier layer.
Preferably the conductive layer is a plating layer and the thickness
thereof can be increased by plating.