Function :                Intern

Contract :               CNRS internship agreement

Starting date:        From February 1st 2026 – At the latest April 1st 2026

Duration:                 6 months

Workplace:             IPVF – 18 boulevard Thomas Gobert, 91120 Palaiseau

Education:              M2 / 3rd year Engineering student

IPVF – Institut Photovoltaïque d’Île-de-France

IPVF is a scientific and technical pole dedicated to the research and development of solar technologies. It permanently hosts its own staff, as well as the employees of its partners and external companies. IPVF aims to become one of the world’s leading centers for research, innovation, and training in the field of energy transition.
IPVF primary objective is to improve the performance and competitiveness of photovoltaic cells and develop breakthrough technologies by relying on four levers:

• Ambitious research program.
• The hosting of more than 200 researchers and their laboratories on its Paris-Saclay site.
• A state-of-the-art technology platform (8,000 m²) open to the photovoltaic industry actors, with more than 100 state-of-the-art equipment units located in clean rooms.
• A training program mainly based on a master’s degree, the supervision of PhD students, and continuing education.

CONTEXT

Solar cells based on metal halide perovskites represent an emerging and promising thin film technology within the field of photovoltaics, yet a current limitation is the long-term stability of the metal halide perovskite (MHP) film when exposed to external stressors including extrinsic species, such as moisture, oxygen or atoms migrating from the electrode layers. A commonly pursued strategy is to grow thin coatings via atomic layer deposition (ALD) on top of the perovskite to act as a permeation barrier. In particular, tin oxide (SnO2) came into the spotlight for its potential as electron transport layer to dramatically increase solar cell stability [1]. However, when deposited directly on a perovskite film, the ALD process induces degradation, which can lead to reduced power conversion efficiency and solar cell with <1% efficiency [2]. Thus, to achieve highly efficient and stable devices, the perovskite film needs to be protected during the ALD process.

One way to achieve that is to add a protective interlayer on top of the perovskite film to prevent contact between the ALD- SnO2 coating and the perovskite. As the MHP film is sensitive to ambient atmosphere, the best-case scenario is to deposit the protective interlayer at the same time as the SnO2 electron transport layer in the ALD setup. For this purpose, we develop an adapted molecular layer deposition (MLD) process [3]. This internship aims at developing a deposition process of an hybrid interlayer by MLD on top of the perovskite to mitigate its degradation caused by the deposition of ALD-SnO2.

This project is part of a thesis funded by the bilateral French-German ANR project ALSATIAN and is hosted at the Institut Photovoltaique d’Ile de France (IPVF).

[1]      J. Christians, P. Schulz et al., ‘Tailored interfaces of unencapsulated perovskite solar cells for >1,000 hour operational stability’, Nature Energys, vol. 3, pp. 68-74, 2018, doi: 10.1038/s41560-017-0067-y.

[2]      N. Mallik et al., ‘Interface defect formation for atomic layer deposition of SnO2 on metal halide perovskites’, Nano Energy, vol. 126, p. 109582, Jul. 2024, doi: 10.1016/j.nanoen.2024.109582.

   [3]      J. Multia and M. Karppinen, ‘Atomic/Molecular Layer Deposition for Designer’s Functional Metal–Organic Materials’, Adv. Mater.
             Interfaces, vol. 9, no. 15, p. 2200210, May 2022, doi: 10.1002/admi.202200210.

MAIN MISSIONS

The main tasks of the internship will be:

– The development and optimization of the hybrid interlayer deposition process by MLD;

– The characterization of the thin film properties (structural, optical, electrical) via advanced characterization techniques such as spectroscopic ellipsometry, grazing incidence X-ray diffraction, and spectrophotometry;

– The characterization of the perovskite film underneath to track its degradation via structural and optical characterization;

-The integration of the thin film in a full PV cell and its (opto-)electrical characterization.

PROFILE

📖 Knowledge

     👉🏼 Training in material science/chemistry and thin film growth and characterization;

     👉🏼 Knowledge in photovoltaics and perovskite solar cells is beneficial;

     👉🏼 Previous work experience in a chemistry lab and/or in clean rooms;

     👉🏼 Competences in data treatment (Microsoft Office, Origin);

💡 Self-management skills

    👉🏼Autonomy and organization skills;

    👉🏼Teamwork and able to present and interpret results;

    👉🏼Curiosity and strong sense of initiative;

    👉🏼Strongly motivated for experimental work.

CONTACT

CV, academic transcripts and cover letter to be sent to: elodie.doressoundiram@cnrs.fr ; philip.schulz@cnrs.fr ; nathanaelle.schneider@cnrs.fr