III-V Material Development and Epitaxy

We develop photovoltaic cells based on III‑V semiconductor compounds, which are composed of elements from the third and fifth groups of the periodic table.

For layer production, we have two modern reactors for industrial-scale metal organic vapor phase epitaxy (MOVPE):

  • An AIX2800 G4-TM reactor with an 8x6-inch configuration
  • A CRIUS showerhead reactor for 7x4-inch or 1x300 mm substrates

 

We Have a Wide Range of Methods Available for Material Characterization:

  • Electrochemical capacitance-voltage (ECV) profiling
  • Spectrally and spatially resolved photoluminescence (PL)
  • Electroluminescence (EL)
  • Cathodoluminescence (CL)
  • X-ray diffraction (XRD)
  • Nomarski differential interference contrast (DIC) microscopy
  • Candela
  • Reflectance anisotropy spectroscopy (RAS)
  • Scanning electron microscopy (SEM)
  • Deep-level transient spectroscopy (DLTS)
  • Electron beam induced current (EBIC) measurements
  • Electron channeling contrast imaging (ECCI)
  • Infrared Fourier spectroscopy
  • Atomic force microscopy (AFM)
  • Hall-Van der Pauw measurements

Our R&D Services on the Topic Include "III-V Material Development and Epitaxy" Include:

  • Monolithic growth of solar cells with up to six sub-cells stacked on top of each other
  • Adaptation to operating conditions (spectrum, intensity, temperature)
  • Development and adaptation of III‑V absorber material
    • AlGaAs, AlGaInP, GaAsP, GaInAs, GaInAsP, and GaInNAs on GaAs or Ge substrates
    • InGaAs, InGaAsP on InP substrates
  • Development of strain-compensated multi-quantum wells
  • Ultra-fast epitaxial processes with growth rates >100 µm/h
  • Direct growth of III‑V semiconductors on silicon substrates for the development of III‑V silicon tandem solar cells
  • Development of metamorphic buffer structures and engineered substrates with adapted lattice constants

R&D Infrastructure

This infrastructure is available to us at Fraunhofer ISE for our research and development activities:

 

Center for High Efficiency Solar Cells

We test and optimize advanced PV technologies in more than 1000 m² of state-of-the-art clean room and laboratory space. Innovative processes and technologies are researched in this center for future use in industry, including wet-chemical processes, photo and laser lithography, nanoimprint laboratory, vapor deposition of metals and dielectrics.

 

CalLab PV Cells

The accredited calibration laboratory CalLab PV Cells at Fraunhofer ISE offers high-precision, reproducible calibrations and measurements of all types of solar cells according to international standards, for example, spectral responsivity/quantum efficiency, reflectance, current-voltage measurements, especially under variable spectra and intensities, various broadband and laser light sources as well as filters are available.

 

Concentrator Technology Evaluation Center Con-TEC

Con-TEC has a wide range of assembly and connection technologies available for the development and assembly of customized modules and packages. We test components and production processes with a focus on reliability and material analysis. We develop prototypes and produce small series to evaluate new components, designs and processes.

 

Lab Structuring and Photonics

We develop solutions based on micro- and nanostructures for solar cells and other photovoltaic components such as photovoltaic cells for transmitting power using laser light, but also for related components such as LEDs.

Selected Reserach-Projects

 

50 Prozent

Monolithic III-V Multi-Junction Solar Cells with More than 50 % Efficiency under Concentrated Irradiation

 

micro-CPV

Development of a Highly Concentrating CPV Module Based on Modern Micro-Production Technology

 

H2Demo

Development of Demonstrators for Direct Solar Water Splitting

 

HIPERION

Hybrid Photovoltaics for Efficiency Record using Integrated Optical Technology

 

QuintuMod

Development of a Low-cost and High Efficient Solar Module Using a Solar Cell with 5-pn Junctions

 

HyCon

Solar Hydrogen Generation Using a HyCon System

 

PoTaSi

Demonstration of the Potential of Monolithic Tandem Solar Cells Made of III-V Semiconductors and Silicon