Work Package 1
Ultra radiation hard multi-junction space solar cell design and epitaxy development
- Theoretical design of radiation hard SBT 4-junction InGaP/InGaP/InGaAsP/Ge solar cell structure for reaching high AM0 efficiency and radiation hardness, minimum target efficiency > 35% before irradiation and > 31% after 1E15 cm-2 and > 27% after 3E15 cm-2 irradiation with 1 MeV electrons.
- Epitaxy structure development for new InGaAsP subcells, new tunnel diodes for metamorphic subcells and new transparent bond layer between the first and second subcell.
- III-V epitaxy development on large area 200 mm Ge wafers to allow for demonstration of 3G30 solar cell devices and bonding tests 1.4 Material analysis to achieve outstanding material quality
WP 2 - Advanced (Ga)InP and Ge substrates
- 100 mm Ge wafers with metamorphic In(Ga)P buffer layer with low threading dislocation density < 5E6 cm-2, sufficient for high efficiency space solar cell growth in WP1
- Demonstrate 200 mm epi-ready germanium wafers suitable for space solar cells
- Roadmap towards up-scaling of cost-effective 200 mm diameter Ge production
WP 3 – Development of industrial wafer bonding processes including characterization
- Development and demonstration of a direct wafer bond process for Ga0.5In0.5P and metamorphic AlInGaAsP/Ge with low electrical resistivity < 500 mOhm cm2
- Development of a precise chemical polishing process for AlInGaAsP/Ge and Ga0.5In0.5P
- First time demonstration of a reliable semiconductor bonding process for solar cell materials on 200 mm diameter Ge and GaAs wafers
WP 4 – Manufacturing of solar cell on up to 200 mm substrates, cell assemblies and coupons
- Demonstrate a manufacturing route for solar cells on 200mm wafers
- Develop design of solar cells on 200mm wafer for maximal utilization of the wafer area
- Manufacture solar cells, solar cell assemblies and coupons for development, demonstration and verification activities in the project
WP 5 – Testing of Solar Cells and Coupons
- Characterization of 4-junction SBT solar cells, relevant component cells and 3G30 solar cells on 200 mm wafers for verification of the achieved cell performance
- Performing confidence tests by particle irradiation exposure and thermal cycling on coupon level for solar cells based on semiconductor bonding technology and solar cells based on 200 mm Ge wafers
- Assessment of the developed cell technology and definition of industrialization roadmap
WP 6 – Dissemination and Exploitation
- To promote the dissemination of the knowledge generated during the project
- To plan and promote the exploitation of the technology developed during the project
- To perform commercial evaluation of developed solar cells and manufacturing technologies
WP 7 – Project Management
The general objectives of this work package is Successful and efficient Operational and Information Management as well as Communication with EC
The essential management goals are to:
- define a Consortium Agreement that is concluded among partners in order to provide rules for a good working relationship and functioning of the consortium, especially with respect to management and exploitation of results
- efficiently establish the consortium structure and verify in a timely approach the coherence and the quality of the project outputs
- provide project oversight and guidance to optimise workflow efficiencies and increase the likelihood of scientific discovery while complying with administrative and reporting requirements of the EC
- implement and successfully maintain an efficient flow of information between the project participants and towards the EC