Multi-Terminal GaInP/GaInAs/Ge Solar Cells for Subcells Characterization

Thomas Bidaud (1, 2) , Farah Ayari (2, 1) , Vincent Aimez (1, 2) , Corentin Jouanneau (2, 1) , Artur Turala (1, 2) , Maxime Darnon (3, 2, 1) , Maïté Volatier (2, 1) , Vincent Aimez (1, 2) , Simon Fafard (1, 2) , Abdelatif Jaouad (1, 2) , Maxime Darnon (3, 2, 1) , Gwenaëlle Hamon (1, 2)

1 LN2 - Laboratoire Nanotechnologies et Nanosystèmes [Sherbrooke]
2 3IT - Institut Interdisciplinaire d'Innovation Technologique [Sherbrooke]
3 LHC - Laboratoire Hubert Curien

Improvement of triple-junction (3J) III-V/Ge solar cells efficiency is hindered by the low current produced by the top and middle cells relative to the bottom cell (Ge). This can be explained by the difficulty of characterizing, on an individual basis, the subcells. We investigate the fabrication process of multi-terminal multi-junction solar cells (MTMJSC) and its potential as a promising architecture to independently characterize subcells of multi-junction solar cells. Here, we study monolithic triple-junction solar cells, with an InGaP top cell, an InGaAs middle cell and a Ge bottom cell interconnected by tunnel junctions. We demonstrate a fabrication process for MTMJSC on commercial wafers for characterization applications purposes. I-V measurements, under illumination, of two-terminals and MTMJSC were compared to validate that the MTMJSC fabrication process does not degrade the cells’ performance. The dark current of each subcell was also measured and an ideal-diode model used to determine the subcells electrical parameters. The results suggest a method to measure the relative absorption and the opto-electrical couplings between the subcells unambiguously, through EQE and electroluminescence measurements, based on basic micro-fabrication processes.

Mots clés: multijunction solar cell multiterminals solar cell characterization external quantum efficiency (EQE); multijunction solar cell; multiterminals solar cell; characterization; external quantum efficiency (EQE)

Domaines: Micro et nanotechnologies/Microélectronique

Thomas Bidaud, Farah Ayari, Vincent Aimez, Corentin Jouanneau, Artur Turala, et al.. Multi-Terminal GaInP/GaInAs/Ge Solar Cells for Subcells Characterization. Energies, 2024, 17 (11), pp.2538. ⟨10.3390/en17112538⟩. ⟨hal-04587190⟩