Improving the metal-semiconductor contact properties for the metallization of silicon solar cells is a major topic of current research within the PV industry, as there is still high potential for efficiency improvement when overcoming the contact-resistance and passivation tradeoff. In this work, we present and investigate the Laser Enhanced Contact Optimization (LECO) process developed by the CE Cell Engineering GmbH. It improves the metal-semiconductor interface properties of crystalline silicon solar cells as it enables a proper electric contact to lowly doped homogeneous emitters whilst the damage on the passivation can be reduced. We firstly present an analysis of the influence of the process on the characteristic properties for a representative batch of monocrystalline p-type PERC cells. In the second step, we demonstrate that LECO is able to make a < 5mOhm∙cm² contact to a 200 Ohm/square homogeneous emitter. Finally, we show that the reduced contact resis-tance is not related to any significant limitation of the passivation and conclude by pointing out its further potential.
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