A thin silicon solar cell having a back dielectric passivation and rear
contact with local back surface field is described. Specifically, the
solar cell may be fabricated from a crystalline silicon wafer having a
thickness from 50 to 500 micrometers. A barrier layer and a dielectric
layer are applied at least to the back surface of the silicon wafer to
protect the silicon wafer from deformation when the rear contact is
formed. At least one opening is made to the dielectric layer. An aluminum
contact that provides a back surface field is formed in the opening and
on the dielectric layer. The aluminum contact may be applied by screen
printing an aluminum paste having from one to 12 atomic percent silicon
and then applying a heat treatment at 750 degrees Celsius.