Innovative encapsulation of solar cells and modules by Atomic Layer Deposition

The nation-wide “Programme et Equipement Prioritaire de Recherche” PEPR TASE (“Technologies Avancées des Systèmes Energétiques”) aims to promote the development of a French industry for new energy technologies, for greater independence, creating jobs and capable of meeting current and future global demand of renewable energies and electrification of uses. The National Strategy has identified three priority sectors, including photovoltaics.
The “BioFlexPV – Biosourced encapsulation materials for flexible photovoltaic modules” project addresses the pressing need for innovative encapsulation technologies that facilitate dismantling and recycling of photovoltaic (PV) modules, while preserving their performance and reliability. Achieving a durable (module lifetime > 25 years), cost-effective encapsulation solution is essential to support the market deployment of PV technologies.
For organic and perovskite-based flexible modules, encapsulation typically involves laminating a plastic barrier film onto the module and sealing it with a UV-curable epoxy resin. These components, derived from non-renewable resources, can represent up to two-thirds of the module's total weight.
BioFlexPV aims to develop new, efficient encapsulation materials sourced from bio-based feedstocks, in order to significantly reduce the environmental impact across various PV technologies. By combining biomass-derived polymers with dense inorganic layers from abundant resources, the project seeks to produce encapsulation films with high gas barrier performance. These new materials will be integrated into a range of flexible PV modules—including crystalline silicon (c-Si), organic PV (OPV), perovskite, and CIGS—and their long-term stability and performance will be thoroughly evaluated.
Thin-film encapsulation using Atomic Layer Deposition (ALD) has already proven effective for devices such as OLEDs. However, several challenges must be overcome for PV applications, including flexibility, temperature tolerance, long-term stability, cost, and throughput. At IPVF, nanolaminate encapsulation layers composed of hybrid organic-inorganic and purely inorganic thin films have been developed using ALD. A key objective of BioFlexPV is to adapt these advanced ALD-based encapsulation strategies to bio-sourced substrates.

The doctoral researcher will benefit from IPVF expertise and unique capabilities in both ALD material development and photovoltaics.
She/he will integrate a dynamic and talented team driven by innovation and results. Using their unique capabilities, her/his main missions will consist in the development of efficient barrier layers for solar cells, ie:
- Development of nanolaminates of inorganic layers (Al2O3, TiO2, SnO2, ZnO) or nanolaminates of hybrid inorganic-organic layers (alucone, titancone, tincone, zincone, … ) on polymer (reference and bio-sourced) substrates
- Characterization of the main material properties required for efficient encapsulation to identify best material solution and understand their behavior: composition, morphology, pinhole density, optical characterizations
- Determination of WVTR measurements of ALD monolayers and multilayers
- Develop analytical models to predict barrier properties of multilayers
- Perform photovoltaic devices encapsulation, ageing tests.
Some characterization will be performed at project partners. In particular, determination of permeation properties and ageing experiments will be performed at CEA INES (Le Bourget du Lac).

IPVF - Institut Photovoltaïque d’Île-de-France, is a global Research, Innovation and Education center, which mission is to accelerate energy transition through science & technology. Gathering industrial PV leaders (EDF, TotalEnergies, Air Liquide, Horiba and Riber) and world-renowned academic research organizations (CNRS, Ecole Polytechnique), multi-disciplinary and international IPVF teams conduct research for clean energy technologies. Supported by the French State, IPVF is labelled Institute for Energy Transition (ITE). IPVF at a glance:
• An ambitious Scientific and Technological Program (6 programs divided in 24 work packages): from tandem solar cell technologies to economy & market assessment, state-of-the art characterization, photocatalysis and breakthrough concepts.
• A state-of-the-art technological platform (8,000m²): more than 100 cutting-edge equipment’s worth €30M, located in cleanrooms (advanced characterization, materials deposition, prototypes for fabrication, modelling…).
• A high-standard Education program (M.S. and PhD students). Website: https://www.ipvf.fr

Knowledge: Materials science, Optical instrumentation, Thin film characterization, Inorganic chemistry

Know-how: Hands-on experience with thin films would be a plus, Data treatment, Communication of results

Self-management skills:  Curious and enterprising, Autonomous, Organizational and collaborative skills, Results-oriented