Selective removal of dielectric layers using picosecond UV pulses

To reduce the cost of energy obtained from photovoltaic cells, advanced cell design and processes are required for solar cell manufacturing. Many of these designs and processes are enabled by laser processing. As the availability of higher power and high beam quality pulsed solid state lasers increases, lasers are expected to find increased application in solar cell manufacturing. Solar cell processing will benefit further as production worthy lasers with picosecond pulse width become available. Picosecond lasers are well suited for selective removal of dielectrics for front and back metallization applications due to reduced thermal effect on the underlying substrate. We present results on silicon nitride and silicon oxide ablation that may find applications in advanced cell architecture.