Diffusion regions of a solar cell are formed using a blanket layer of film that is doped with dopants of a first conductivity type. Dopants of a second conductivity type are implanted in select regions of the blanket layer of film to form dopant source regions of the second conductivity type. Diffusion regions of the solar cell are formed by diffusing dopants of the first conductivity type and dopants of the second conductivity type from the blanket layer of film into an underlying silicon material. The blanket layer of film may be a P-type dopant source layer doped with boron, with phosphorus being implanted in select regions of the P-type dopant source layer to form N-type dopant source regions in the P-type dopant source layer.