All‐Angle Invisibility Cloaking of Contact Fingers on Solar Cells by Refractive Free‐Form Surfaces

  title={All‐Angle Invisibility Cloaking of Contact Fingers on Solar Cells by Refractive Free‐Form Surfaces},
  author={Martin F. Schumann and Malte Langenhorst and Michael Smeets and Kaining Ding and Ulrich Wilhelm Paetzold and Martin Wegener},
  journal={Advanced Optical Materials},
This work demonstrates a performance improvement of state‐of‐the‐art silicon solar cells by cloaking their metal contact fingers. The cloaking free‐form surfaces are fabricated on silicon heterojunction solar cells using direct laser writing of polymers and subsequent soft imprinting. Cloaking performance is determined experimentally by measuring spatially resolved and angle‐resolved current generation and the spectral response of the cell. The short‐circuit current density of the cell… 

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