The 6th SiTaSol Project Review was kindly hosted by the University of Leiden in the city of Leiden, located in the southern region of The Netherlands.
The project has been ongoing since May 2017 and this review meeting marked the three quarter stage of the project. This meeting was an important milestone within the project and therefore attended by the project leaders from all members of the consortium. This included the EU Project Officer Francesca Harris, given technical support by external expert advisors.
During the review meeting, we consolidated the development of GaAsP/Si tandem solar cells by direct growth and exchanged on the schedule for bringing the different process steps together. Si substrates without CMP polishing are delivered by TopSil, diffusion of the Si emitter and growth of GaP/GaAsP buffer layers is done at Fraunhofer ISE before the wafers are schipped to Aixtron. Here the tunnel diode and III-V solar cell absorber layer is grown.
Further processing is done at Joanneum Research and finally testing at AZUR Space and Fraunhofer ISE. The processing sequence is truly European and involves nearly all partners. Further focus in the last year is given to completing the life cycle analysis, energy yield and cost model. With this we hope to generate very valuable insight into the potential of the III-V/Si tandem technology.