Continuous roll-to-roll fabrication of organic photovoltaic cells via interconnected high-vacuum and low-pressure organic vapor phase deposition systems

Abstract

We demonstrate continuous roll-to-roll (R2R) fabrication of single junction and tandem organic photovoltaic (OPV) cells on flexible plastic substrates employing a system that integrates organic deposition by high vacuum thermal evaporation (VTE) and low pressure organic vapor phase deposition (OVPD). By moving the substrate from chamber to chamber and then depositing films on stationary substrates, we achieve power conversion efficiencies of PCE = 8.6 ± 0.3% and 8.9 ± 0.2% for the single junction and tandem cells, respectively. Single junction OPVs are also fabricated on a continuously translating substrate at 0.3 cm/s, to achieve PCE = 8.5 ± 0.2%. Thin films grown on translating substrates by OVPD show <3% thickness non-uniformity and 0.66 nm root mean square surface roughness, similar to that obtained by VTE. Our results suggest that R2R film deposition comprising multiple vapor deposition technologies is a promising method for rapid speed and continuous manufacturing of high quality, small molecular weight organic electronic materials.

Thermally evaporated methylammonium-free perovskite solar cells

“…20 In particular, thermal evaporation is a well-established process, commonly utilised for the fabrication of other emerging photovoltaic technologies, such as organic solar cells. 21,22 Since the demonstration of the first thermally evaporated methylammonium lead mixed halide (iodide/chloride) perovskite solar cell, 23 most of the research on evaporated perovskite solar cells focused on methylammonium lead triiodide (MAPbI 3 ). [24][25][26][27][28][29] It had been recognised already at the early stages of research that evaporation of methylammonium iodide (MAI) is difficult to control and to perform reproducibly, 30 prompting researchers to explore other, MA-free, perovskite compositions for thermal evaporation.…”

Near‐Infrared Ternary Tandem Solar Cells

“…Organic photovoltaics (OPVs), have the potential for producing low-cost and ubiquitous renewable energy in the future, due to their reliance on abundant and environmentally friendly carbon-based materials. Furthermore, their ability to be deposited on flexible, light weight and transparent substrates provides a path to mass production via continuous roll-to-roll deposition [1] . By stacking both large and small energy-gap cells into a tandem OPV, the efficiency can be improved by minimizing the thermalization losses [2][3][4][5] .…”

Organic Solar Cells—The Path to Commercial Success

“…[ 3 ] Their key advantages are in particular that organic semiconductors can be tailored for purpose, are based on abundant and non‐toxic raw materials, and the used manufacturing technologies, primarily vacuum coating and solution processing, are in principle capable of coating large areas inexpensively and fast. [ 4,5 ] This, combined with little material consumption (≈1 g organic semiconductor per m 2 ), low‐temperature processing and the compatibility with flexible substrates enables light‐weight devices made in roll‐to‐roll production and a large versatility in applications. This could make OSC the cheapest source of electricity in the world.…”