Characterization & Cell Calibration

At Fraunhofer ISE, characterization and simulation of materials and cells play a major role in our cell development research. For the tandem technology, we carry out material analyses (silicon, III-V, perovskite crystals and layers) and cell characterization using many different approaches. Also our accredited calibration laboratory CalLab PV Cells is a valuable resource, providing quality assurance, traceable measurements and allowing for the comparison of devices with different materials, sizes and cell technologies. We work closely with industry to optimize the performance of conventional and novel solar cell technologies.

Characterization and Simulation

Wavelength-dependent PL analysis of perovskite-silicon tandem solar cells
© Fraunhofer ISE
Cell Analysis: Wavelength-dependent PL analysis of perovskite-silicon tandem solar cells reveals spatially resolved properties of the different subcells.

In our laboratories, characterization measurements are performed ex-situ as well as in-situ during processing and cover a large range of approaches. Among these are spectral response and quantum efficiency measurements, I-V characteristics, camera-based luminescence and lock-in thermography measurements as well as microscopic techniques like microscopic photoluminescence or SEM-based techniques.

Combined with cell simulations based on different platforms (Sentaurus TCAD, Quokka), we can determine cell performance and identify losses. Based on our results, we provide detailed assistance for further cell optimization. Visit our other websites for more detailed information.


Nondestructive probing of perovskite silicon tandem solar cells using multiwavelength photoluminescence mapping

Cell Calibration

Spectral response measurement of a multijunction solar cell
© Fraunhofer ISE
Spectral response measurement of a multijunction solar cell in the grating monochromator test bench. In addition to the green test illumination, blue bias light can be seen, which is used to bring the sub-cell to be measured into a currentlimited state.

For over 30 years, we have been providing high-precision solar cell calibrations and comprehensive measurement services in our internationally renowned accredited calibration laboratory CalLab PV Cells. At our facilities, we characterize a wide variety of solar cell types with high accuracy and precision in accordance with international standards, serving industry and research around the world. For tandem solar cells, our services include wavelength-dependent spectral response measurements, several multi-source simulators for precise tandem measurements up to six junctions. With these simulators we achieve highest precision for IV and EQE measurements under a wide range of temperature and irradiation conditions (STC and others). Potential time dependencies or hysteresis effects are carefully considered.


  • Long-standing measurement expertise on concentrator, space and terrestrial tandem solar cells
  • Sophisticated measurement setups, which may be adapted to the special needs of novel solar cell technologies (multi-junction, bifacial, etc.) for any reference spectrum
  • Very precise measurement procedures provide repeatedly reliable results for e.g. metastable cells

Our R&D Services on this Topic:

Accredited Lab

CalLab PV Cells

Calibration of solar cells and mini PV modules

Research Topic