Function: Intern
Contract: Internship agreement
Starting date: As of February 1st, 2024
Duration: 6 months
Wrokplace: ILV – 45 Av. des États Unis, 78000 Versailles (80% of time)
IPVF – 18 bd Thomas Gobert, 91120 Palaiseau (20%of time)
Education: Master 2 or 3A Engineer
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.
Brief history:
The IPVF was founded in 2013 on the initiative of the French government, EDF, TotalEnergies, Air Liquide, CNRS, Ecole Polytechnique, Horiba and Riber. Bringing together more than 150 researchers, our 8,000 square meter Paris-Saclay platform is a unique platform for all types of deeptech research and innovation.
The IPVF aims to remain:
• A world leader in photovoltaic-related R&D. By federating the best French teams in the field of research, innovation and industrial production, in partnership with major international institutes, particularly in Europe,
• A leader in the development of photovoltaic technology bricks in line with market trends,
• A reference in sending the most promising R&D concepts to the industry.
In recent years, a significant number of studies on perovskite solar cells development have been conducted. This devotion is explained by the high potential of the perovskite active layer, which allows achieving competitive efficiencies with silicon, with a new record of 26.1% set in July [1], all while maintaining a reasonable manufacturing cost. These results are the fruit of numerous research efforts focused on optimizing the chemical structure of perovskite, as well as the solar cell structure itself, by incorporating charge carrier transport layers, defect passivation layers, or protective layers. These layers play a crucial role in improving the efficiency and stability of these devices. Notably, it is important to control the quality of the interfaces between these stacked layers [2], which requires a means to access buried interfaces in increasingly complex cell architectures. In this framework, this internship focuses on optimizing the GDOES/XPS coupling for advanced chemical characterization at interfaces.
The objective of this internship is to employ two characterization techniques, XPS (X-ray Photoelectron Spectroscopy) and GDOES (Glow Discharge Optical Emission Spectroscopy), which will be applied in a consecutive coupled way. The idea is to take advantage of the fast sputtering of the GDOES plasma and then perform a detailed analysis of the chemistry of the interfaces using XPS. Initially, the study will be carried out on a complete solar cell with a perovskite active layer, and then be extended to the case of a tandem cell (perovskite/silicon, for example) with an even more complex architecture. Tandem architectures are increasingly considered because they offer an interesting perspective for the commercialization of third-generation thin-film photovoltaic modules [3]. They allow for higher efficiency over a wider wavelength range, surpassing the Shockley-Queisser limit that restricts the efficiency of single-junction cells.
During this internship, the focus will be on characterizing the different buried interfaces and following the changes occurring at their level after aging. Optimization and adjustment of GDOES operating conditions will be carried out to maximize the integrity of the chemical information collected using different plasma gases (Ar, Ar/O, Ne). Other structural and optical characterizations may also be conducted to better understand the aging and instability mechanisms, ultimately addressing current technological challenges. This methodology of coupling quantitative (XPS) and qualitative (GDOES) characterization is a very promising approach that has already been applied and validated on photovoltaic absorbers such as CIGS layers and III-V materials [4] [5].
[1] https://www.nrel.gov/pv/interactive-cell-efficiency.html
[2] P. Schulz et al. (2019). Chemical reviews, 119(5), 3349-3417.
[3] N.N. Lal et al. (2017). Advanced Energy Materials, 7(18), 1602761.
[4] D. Mercier et al. (2015). Applied Surface Science, 347, 799-807
[5] S. Béchu et al. (2019). Journal of Vacuum Science & Technology B, 37(6).
This internship is part of a collaborative project between IPVF (Photovoltaic Institute of Île-de-France) and ILV (Lavoisier Institute of Versailles), where it will primarily take place. The idea here is to develop an innovative methodology for characterizing buried interfaces by leveraging two chemical analysis techniques: GDOES and XPS. GDOES is a semi-quantitative technique that allows for fast depth profiling, providing quick access to deeply buried areas of specific interest. XPS is a surface analysis technique that provides information on atomic composition and chemical environments.
The intern will be trained for these techniques, and his/her work will initially focus on optimizing/adapting the operating conditions of GDOES on different structures (model structures and complete cells) using various plasma gases (Ar, Ar/O, Ne) to minimize the degradation of chemical information. The obtained crater will then be further studied by XPS to obtain precise quantitative information about the nature of the species present. We will pay particular attention to the interface zones between perovskite and ETL or HTL, with the goal of studying a complete solar cell in segments. Additional optical and structural characterizations (SEM, AFM, PL, etc.) will also be conducted to better understand the interactions between the plasma, X-rays, and the bombardment of Ar ions and validate the reliability of the method. Subsequently, the modifications induced by changing the layer stacking will be studied, more specifically its effect on the physico-chemistry of interfaces, especially those with the perovskite active layer, before and after aging.
– Knowledge of physico-chemistry of materials
– Thin films characterization Caractérisation de couches minces (will be a plus)
– Public expression, oral communication and writting
– Adaptability
– Teamwork
– Autonomy
– Senses of organization
CV and cover letter to be sent to:
Feel free to contact us for more information about our offers.
+33(0)1 69 86 58 60
contact@ipvf.fr
