Novel R2R fabrication process for high quality transparent electrode nanolayers for
cost-effective manufacturing of flexible Organic Photovoltaics
S. Logothetidis
Lab for Thin Films-Nanobiomaterials-Nanosystems & Nanometrology (LTFN)
Physics Department, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
e-mail:
tel.: +302310998174
Flexible Organic and printed Photovoltaics (OPVs) have attracted an enormous interest in the
modern science & industry, due to their several advantages that include conformability to
curved surfaces and potentiality for fabrication by low-cost production processes such as roll-
to-roll (R2R) printing. The optimization of the quality of the printed nanomaterials
(transparent electrodes, organic semiconductors etc.) on flexible polymer substrates (e.g.
PolyEthylene Terephthalate-PET), and the blend morphology of the photoactive layer is a
prerequisite for the achievement of the required performance, efficiency and lifetime of
OPVs in order to allow their market commercialization. The quality of the printed layers is
controlled by the nanomaterials properties and the R2R processes parameters such as the
printing speed and drying conditions.
In this work, we describe a novel approach for the fabrication of high quality transparent
electrodes (e.g. ZnO, PEDOT:PSS) in multilayer OPV device architectures by R2R printing
in combination with laser scribing (in both sheet-to-sheet and roll-to-roll configurations) of
the different OPV layers (transparent electrodes, photoactive layers, metal electrodes). The
printing parameters were optimized by the contribution from extensive analytical
characterization, as well as from robust in-line optical metrology that includes Spectroscopic
Ellipsometry (SE) for the determination of the printed nanolayers thickness, optical
properties, bonding structure and photoactive layer blend morphology. The perspective of
this approach is to significantly improve the manufacturing technologies for large area
fabrication of high performance and stability devices (OPVs, OLEDs, OTFTs, etc.) in
combination with low-cost and high commercialization potential.
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