Industrial Si solar cells with Cu based plated contacts

Despite big progress with respect to improving Ag pastes for contact formation on Si solar cells most of today´s Si solar cells are significantly limited in their performance by the front contacts and the constraints that these contacts impose on front emitter diffusion and surface passivation. Furthermore, Ag contacts are imposing a high consumable cost. This work demonstrates that laser ablation followed by nickel and copper plating and a thermal anneal results in improved performance and reduced cost for solar cells and modules. LID stabilized efficiencies exceeding 20.8% on p-type PERC cells have been independently confirmed by FhG-ISE CalLab. Average fill factors up to 80.8% have been demonstrated on large area solar cells with emitter P concentrations of <;4*10¹⁹ P/cm³ and Al BSF rear sides.