Cycle efficiency: reuse of germanium substrates

Dr. Frank Dimroth

Dirk Mahler

Contact: III-V Photovoltaics and Concentrator Technology Division Photovoltaics Fraunhofer Institute for Solar Energy Systems ISE Heidenhofstraße 2 79110 Freiburgfrank.dimroth@ise.fraunhofer.de

Dr. Charlotte Weiss

Contact:Silicon Materials & Epitaxial Wafers Division Photovoltaics Fraunhofer Institute for Solar Energy Systems ISE Heidenhofstraße 2 79110 Freiburgcharlotte.weiss@ise.fraunhofer.de

Dr. Marion Drießen

Contact: Photovoltaics, Silicon Materials & Epitaxial Wafers Fraunhofer Institute for Solar Energy Systems ISE Heidenhofstraße 2 79110 Freiburgmarion.driessen@ise.fraunhofer.de

Tasks in the project:

  • Production of porous Ge substrates
  • Production of III-V compound semiconductors on porous Ge or on Ge with AlAs interlayer and analysis of the material quality
  • Development of process sequences for the production of the modified Ge substrates, the epitaxy, the stabilization of the III-V layers (by silicon or electrodeposited Cu) and the detachment of the III-V layers
  • Preparation of the Ge substrates and proof that they can be used multiple times

Proof of high-efficiency III-V solar cellsProof of high-efficiency III-V solar cells

Methods:

  • Electochemical etching,
  • Metal-organic vapor phase epitaxy,
  • Scanning electron microscopy,
  • Atomic force microscopy,
  • X-ray diffractometry,
  • in situ reflection,
  • photoluminescence

For more information:

III-V Solar Cells, Modules and Concentrating Photovoltaics - Fraunhofer ISE

Material technologies - Fraunhofer ISE