Thinned Germanium Substrates for III-V Multijunction Solar Cells

  title={Thinned Germanium Substrates for III-V Multijunction Solar Cells},
  author={Iv{\'a}n Lombardero and Naoya Miyashita and Mario Ochoa and Yoshitaka Okada and Carlos Algora},
  journal={2019 IEEE 46th Photovoltaic Specialists Conference (PVSC)},
Multijunction solar cells are usually grown on Ge substrates. This implies several disadvantages that hinder the performance of the whole multijunction and limit their possible applications. The drawbacks caused by the substrate are: heavier devices, higher operation temperatures, lower performance and lack of photon confinement. In this work we propose thinning the substrate as a valid solution to the aforementioned challenges. The influence of the substrate thickness on the Ge subcell… 

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