LASER DRILLING OF VIAS IN BACK CONTACT SOLAR CELLS

摘要

Embodiments of the invention relate to methods and apparatus for laser drilling holes in a silicon substrate during the fabrication of back contact solar cells, such as emitter-wrap-through (EWT) solar cells. In one embodiment, the method and apparatus use a short focal length flat field lens and a dynamic scanning technique to accomplish single pulse drilling in the silicon substrate. The method and apparatus result in increased speed and quality of holes in an EWT solar cell substrate as compared to conventional apparatus and processes.