Towards quantitative interpretation of Fourier-transform photocurrent spectroscopy on thin-film solar cells

0538302 - FZÚ 2021 RIV CH eng J - Journal Article
Holovský, Jakub - Stuckelberger, M. - Finsterle, T. - Conrad, B. - Amalathas, A.P. - Müller, Martin - Haug, F.J.
Towards quantitative interpretation of Fourier-transform photocurrent spectroscopy on thin-film solar cells.
Coatings. Roč. 10, č. 9 (2020), s. 1-9, č. článku 820. E-ISSN 2079-6412
R&D Projects: GA MŠMT(CZ) EF16_019/0000760; GA ČR GA18-24268S
Grant - others:OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institutional support: RVO:68378271
Keywords : solar cells * photocurrent spectroscopy * defect density * amorphous silicon * open-circuit voltage * radiative limit
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 2.881, year: 2020
Method of publishing: Open access

The method of detecting deep defects in photovoltaic materials by Fourier-Transform Photocurrent Spectroscopy is reviewed. As new materials appear, a prediction of potentially achievable open-circuit voltage is highly desirable. From thermodynamics, a prediction can be made based on the radiative limit, neglecting non-radiative recombination and carrier transport effects. Beyond this, more accurate analysis has to be done. We analyzed a series of hydrogenated amorphous silicon solar cells of different thicknesses at different states of light soaking. Combining empirical results with optical, electrical and thermodynamic simulations, we provide a predictive model of the open-circuit voltage for a given defect density and absorber thickness. We observed that, rather than defect density or thickness, it is the total number of defects, that matters. Alternatively, including defect absorption into the thermodynamic radiative limit gives also useful upper bound to the open-circuit voltage.
Permanent Link: http://hdl.handle.net/11104/0316124