Work Packages

Work Package 1

Ultra radiation hard multi-junction space solar cell design and epitaxy development

  1. 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.
  2. Epitaxy structure development for new InGaAsP subcells, new tunnel diodes for metamorphic subcells and new transparent bond layer between the first and second subcell.
  3. 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

  1. 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
  2. Demonstrate 200 mm epi-ready germanium wafers suitable for space solar cells
  3. Roadmap towards up-scaling of cost-effective 200 mm diameter Ge production

WP 3 – Development of industrial wafer bonding processes including characterization

  1. Development and demonstration of a direct wafer bond process for Ga0.5In0.5P and metamorphic AlInGaAsP/Ge with low electrical resistivity < 500 mOhm cm2
  2. Development of a precise chemical polishing process for AlInGaAsP/Ge and Ga0.5In0.5P
  3. 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

  1. Demonstrate a manufacturing route for solar cells on 200mm wafers
  2. Develop design of solar cells on 200mm wafer for maximal utilization of the wafer area
  3. 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

  1. 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
  2. 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
  3. Assessment of the developed cell technology and definition of industrialization roadmap

WP 6 – Dissemination and Exploitation

  1. To promote the dissemination of the knowledge generated during the project
  2. To plan and promote the exploitation of the technology developed during the project
  3. 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