Missions

A postdoctoral position is open in the group of Jesus Zuniga-Perez (CRHEA, Université Côte d'Azur-CNRS), as part of the ANR project SPOIR. The postdoc will be in charge of developing the epitaxial growth of halide perovskites by molecular beam epitaxy and of characterizing their structural, morphological, electrical and optical properties, assessing in particular their stability under ambient conditions. Once the growth halide perovskites compounds will be mastered, the postdoc will perform the growth and analysis of novel quantum heterostructures.

About the project.
The project SPOIR, “Stable perovskites for solar cells”, aims to explore the synthesis and growth of pure-phase single-crystalline inorganic halide perovskites (HPs) CsMX3 thin films, with M = (Pb,Sn) and X = (I,Br), for photovoltaic and opto-electronic applications. The underlying idea is to develop single-crystal thin films instead of the most standard polycrystalline films, and improve thereby their stability as well as their optoelectronic figures of merit (carrier diffusion lengths and nonradiative recombination centres density). CRHEA will be in charge of the growth of halides perovskites by molecular beam epitaxy (MBE), which is the technique of choice for the most advanced optoelectronic heterostructures and lasers or high-mobility transistors. However, MBE has been scarcely used in the field of perovskites, although it promises access to high-crystalline quality materials available until now only as bulk crystals. The second goal of the project, in line with the development of a stable and sustainable solar technology based on perovskites, is to synthetize inorganic Pb-free HPs. The development of Sn-based perovskites is expected to play an important role in upcoming sustainable HP-based solar cells and optoelectronic devices.
The consortium gathers three partners, including LUMIN (Paris-Saclay University), INSP (Sorbonne University) and CRHEA (Cote d'Azur University), all of them affiliated to CNRS .

Activities

The postdoc will work on the molecular beam epitaxy growth of halides perovskites on a devoted reactor available in CRHEA. The candidate will then characterize the morphological, structural, electrical and optical properties of the thin films, and will fabricate test devices in CRHEA's clean room. For more advanced optical characterizations, the candidate will perform additional experiments during research stays at our collaborator laboratories. Upon mastering the growth of several ternary compounds, the postdoc will assess the possibility of building quantum heterostructures based on single-crystalline perovskites, which has not yet been demonstrated. This will open numerous possibilities in terms of applications and fundamental physics.
The postdoc will be supervised by C. Deparis, E. Frayssinet and J. Zuniga-Perez.

Skills

Qualifications:
- PhD in materials science or devices nanofabrication.
- Hands-on experience with growth reactors and/or clean-room environment.
- Knowledge of structural and/or optical characterization of semiconductors.
- Knowledge of numerical simulations will be useful though not necessary.
- Excellent analytical, organizational, and communication skills.
- Creativity and ability to think out of the box.

Work Context

About the hosting group.
The team of Jesus Zuniga Perez (CNRS) has been working on the field of epitaxial growth of semiconductors for more than 15 years, developing high-quality ZnO and GaN heterostructures as well as introducing the epitaxial growth of new semiconductors. Central to the SPOIR project will be the recent modification of a molecular beam epitaxy reactor to handle corrosive environment brought about by the halide compounds.

Working environment.
CRHEA (Centre de Recherche sur l'Hétéro-Epitaxie et ses Applications, Université Côte d'Azur-CNRS): The laboratory is leader on the field of wide bandgap semiconductor material epitaxy and has been leading the Labex “GaNeX/t” dedicated to GaN. CRHEA has developed a unique expertise on fabrication of optoelectronic devices, from solar cells to LEDs and lasers, as well as electronic devices including high-electron mobility transistors. The team has the expertise and the tools necessary for the structural and optical characterization of the materials to be grown as well as the necessary clean-room technology for fabricating proof-of-concept optoelectronic devices.

In CRHEA the postdoc will interact strongly with Christiane Deparis, Eric Frayssinet and Jesus Zuniga-Perez (involved in the MBE growth of perovskites), the clean-room team (Virginie Brändli, Sebastien Chenot, and Maksym Gromovyii), Mathieu Leroux (for the optical characterization), Maxime Hugues (for the electrical characterization) and Maud Nemoz and Ileana Florea (for the structural characterization).

The position is located in a sector under the protection of scientific and technical potential (PPST), and therefore requires, in accordance with the regulations, that your arrival is authorized by the competent authority of the MESR.

Constraints and risks

What We Offer:
- Opportunity to work on an innovative project and to play an instrumental role in the structuration of the burgeoning field of perovskites devices.
- Opportunity to supervise interns.
- Various collaborations in France, Europe and Singapore within highly stimulating environments.
- Excellent networking opportunities with leading experts from academia and industry.
- Excellent working conditions with competitive salary and benefits

Interested candidates should submit their application by sending a detailed CV, a cover letter explaining their interest and previous background and a list of publications.