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Title: Self-assembled multifunctional nanostructures for surface passivation and photon management in silicon photovoltaics
Abstract This work reports the fabrication and characterization of multifunctional, nanostructured passivation layers formed using a self-assembly process that provide both surface passivation and improved light trapping in crystalline silicon photovoltaic (PV) cells. Scalable block copolymer self-assembly and vapor phase infiltration processes are used to form arrays of aluminum oxide nanostructures (Al 2 O 3 ) on crystalline silicon without substrate etching. The Al 2 O 3 nanostructures are characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and spectroscopic ellipsometry. Injection-level dependent photoconductance measurements are used to determine the effective carrier lifetime of the samples to confirm the nanostructures successfully passivate the Si surface. Finite element method simulations and reflectance measurement show that the nanostructures increase the internal rear reflectance of the PV cell by suppressing the parasitic optical losses in the metal contact. An optimized morphology of the structures is identified for their potential use in PV cells as multifunctional materials providing surface passivation, photon management, and carrier transport pathways.  more » « less
Award ID(s):
1650002
PAR ID:
10405891
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Nanophotonics
Volume:
10
Issue:
18
ISSN:
2192-8614
Page Range / eLocation ID:
4611 to 4621
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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