Tracking Hydrogen During Poly-Si/SiOx Contact Fabrication: An Infrared Spectroscopy Analysis of Si–H Bonds Configurations




Silicon Solar Cells, Poly-Silicon, Hydrogen, TOPCon, FTIR


The hydrogenation step contributing to the high efficiencies (>25%) reached with poly-Si/SiOx passivated contacts solar cells is still poorly understood. In this study, Fourier transform infrared spectroscopy (FTIR) is used to follow the different bonding configurations of H during the fabrication process. The carrier lifetime degradation upon annealing is correlated to an important loss of Si–H bonds, from both the a­‑Si:H film and the SiOx interfaces. The subsequent hydrogenation step results in the formation of a small number of Si–H bonds near the crystalline silicon c-Si/SiOx interface, associated with the low stretching mode (LSM) and correlated to a significant lifetime improvement. These bonds feature a preferential orientation, as shown by polarized measurements.


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How to Cite

Bocquet, V., Cabal, R., Albaric, M., Rochat, N., Ramos, R., Barnes, J.-P., & Dubois, S. (2024). Tracking Hydrogen During Poly-Si/SiOx Contact Fabrication: An Infrared Spectroscopy Analysis of Si–H Bonds Configurations. SiliconPV Conference Proceedings, 1.

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