High‐Efficiency GaAs Solar Cells Grown on Porous Germanium Substrate with PEELER Technology

Abstract

III‐V solar cells are mainly grown on GaAs or Ge substrate, which significantly contributes to the final cost and affects the sustainable use of these rare materials. We developed a so‐called PEELER process in which a porosification technique is used to create a weak layer between a Ge substrate and the epitaxial layers. This method enables the separation of the grown layers, allowing for the subsequent reuse of germanium and a reduction in the environmental and economic cost of optoelectronic devices. Technology validation using the device performance is important to assess the technology interest. For this purpose, we fabricated and compared the performance of 22 non‐detached single‐junction (s‐j) GaAs photovoltaic cells grown and manufactured on porosified 100mm Ge wafer without anti‐reflection coating (ARC). All the cells exhibit comparable performance to state‐of‐the‐art GaAs solar cells (grown or Ge or GaAs) with high efficiency (21.8% ± 0.78%) and thereby demonstrate the viability of growing high‐performance optoelectronic devices on detachable Ge films.This article is protected by copyright. All rights reserved.