SPACE TECH EXPO Europe – 19 to 21 November 2019 – Bremen, Germany

Europe's meeting place for space business, technology & innovation.

Space Tech Expo Europe returns to Bremen, Germany on 19-21 November 2019, drawing attendance of more than 4000 industry leaders, decision makers, engineers, specifiers and buyers to meet manufacturers and the entire space supply chain. The free-to-attend trade fair will showcase the very latest technology from technical designers, electrical and avionic sub-systems suppliers, manufacturers and components through to systems integrators for (aero) space.

For more information, and to register for your free pass, please visit

Meet tf2 devices at stand 5018 at the Space Tech Expo in Bremen, from 19 to 21 November.

Triple-junction Inverted MetaMorphic (IMM3J) ELO solar cells with an area of 30 cm2 have been successfully manufactured by tf2 devices and Fraunhofer-ISE as part of ESA project 4000117911. The power-to-mass ratio of these solar cells is more than 2.0 W/g for the AM0 spectrum, well above the 0.5 to 0.9 W/g typically achieved by state-of-the-art space solar cells. This is a key property for applications in space and solar powered UAVs such as HAPS/HALE. The large area of the ELO solar cells demonstrates the maturity of the ELO technology and the associated thin-film processing techniques.

Fraunhofer-ISE provided the IMM3J epitaxial layer structures. Using the ELO technique tf2 devices separated the IMM3J structures from their native wafer and processed these into the above mentioned fully functional solar cells. Since the costly wafers can now be reused multiple times for subsequent epitaxial growth cycles, this not only saves costs but also precious raw materials. The flexible nature of the ELO solar cells opens new possibilities for flexible space solar panels, leading to additional mass savings and more efficient stowage during launch.

The business strategy of tf2 devices involves continuous developments to further reduce the cost per watt-peak for ELO solar cells, and the early engagement in the development of high-efficiency III-V semiconductor devices that have a large potential for added performance in a thin-film geometry and cost reduction by substrate reuse. Part of this research and development is performed within several European research projects.

One of the projects tf2 devices is involved in is ALFAMA, which stands for ‘Advanced Lightweight and Flexible Array with Mechanical Architecture’, under the European Union’s Horizon 2020 research and innovation programme. Together with partners Fraunhofer ISE, CEA, Airbus Defence and Space Netherlands, France and Germany, AZUR Space and Absiskey, the objective is to develop a flexible III-V solar array for space applications. In the frame of ALFAMA, tf2 devices will perform ELO and subsequent thin-film processing to produce triple-junction Inverted MetaMorphic ELO solar cells to be integrated in the flexible III-V solar array.

In April 2017 the CASOLBA (CAlibration of SOLar cells using BAlloon flight) flight by the French National Centre for Space Studies (CNES) successfully took place. Using a stratospheric balloon flight at an altitude of 34 to 37 km, the solar cells on board were electronically monitored while being exposed to irradiance closely approaching the Air Mass 0 (AM0) spectrum, for temperatures ranging from -10 to +50 °C. One solar cell slot was offered to tf2 devices by the European Space Agency (ESA), and the ELO solar cell concerned performed perfectly.

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