Fabrication of 4-cm2 35.2% SBT 5J solar cells

In this paper, we report on our recent process in SBT 5J space solar cells. The results of top three junctions inverted grown on GaAs, bottom two junctions upright grown on InP and broadband low-reflectivity anti-reflection coatings are presented. Based on these results, we manage to fabricate 1-sun, AM0 ~35.2% 5J cells through structure tunning, band engineering and material tailoring. The cell presents a Voc of 4.95V, an Isc of 11.34mA/cm
²
and an ff of 0.848. With further detailed optical tunning and band engineering to improve the output current, a target efficiency of 36%, or above, could be expected.