title: Experimental quantification of useful and parasitic absorption of light in plasmon-enhanced thin silicon films for solar cells application.
abstract: A combination of photocurrent and photothermal spectroscopic techniques is applied to experimentally quantify the useful and parasitic absorption of light in thin hydrogenated microcrystalline silicon (μc-Si:H) films incorporating optimized metal nanoparticle arrays, located at the rear surface, for improved light trapping via resonant plasmonic scattering. The photothermal technique accounts for the total absorptance and the photocurrent signal accounts only for the photons absorbed in the μc-Si:H layer (useful absorptance); therefore, the method allows for independent quantification of the useful and parasitic absorptance of the plasmonic (or any other) light trapping structure. We demonstrate that with a 0.9 μm thick absorber layer the optical losses related to the plasmonic light trapping in the whole structure are insignificant below 730 nm, above which they increase rapidly with increasing illumination wavelength. An average useful absorption of 43% and an average parasitic absorption of 19% over 400-1100 nm wavelength range is measured for μc-Si:H films deposited on optimized self-assembled Ag nanoparticles coupled with a flat mirror (plasmonic back reflector). For this sample, we demonstrate a significant broadband enhancement of the useful absorption resulting in the achievement of 91% of the maximum theoretical Lambertian limit of absorption.
authors.affiliation: MATIS IMM-CNR, via S. Sofia 64, I-95123 Catania, Italy.|Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, I-95123 Catania, Italy.
authors.forename: Seweryn
authors.initials: S
authors.lastname: Morawiec
authors.affiliation: Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnicka 10, Prague, Czech Republic.
authors.forename: Jakub
authors.initials: J
authors.lastname: Holovský
authors.affiliation: MATIS IMM-CNR, via S. Sofia 64, I-95123 Catania, Italy.|i3N/CENIMAT, Department of Materials Science, Faculty of Science and Technology, Universidade NOVA de Lisboa and CEMOP/UNINOVA, Campus de Caparica, 2829-516 Caparica, Portugal.
authors.forename: Manuel J
authors.initials: MJ
authors.lastname: Mendes
authors.affiliation: Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnicka 10, Prague, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Müller
authors.affiliation: Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnicka 10, Prague, Czech Republic.
authors.forename: Kristina
authors.initials: K
authors.lastname: Ganzerová
authors.affiliation: Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnicka 10, Prague, Czech Republic.
authors.forename: Aliaksei
authors.initials: A
authors.lastname: Vetushka
authors.affiliation: Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnicka 10, Prague, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Ledinský
authors.affiliation: MATIS IMM-CNR, via S. Sofia 64, I-95123 Catania, Italy.|Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, I-95123 Catania, Italy.|Scuola Superiore di Catania, Università di Catania, via Valdisavoia 9, 95123 Catania, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Priolo
authors.affiliation: Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnicka 10, Prague, Czech Republic.
authors.forename: Antonin
authors.initials: A
authors.lastname: Fejfar
authors.affiliation: MATIS IMM-CNR, via S. Sofia 64, I-95123 Catania, Italy.|Department of Energy, Information Engineering and Mathematical Models (DEIM), University of Palermo, Viale delle Scienze, Building 9, I-90128 Palermo, ITALY.
authors.forename: Isodiana
authors.initials: I
authors.lastname: Crupi