The aim of this thesis is to exploit the remarkable properties of functional oxides for electronics. La0.7Sr0.3MnO3 (LSMO) belongs to this family of functional oxides, oxides with strongly correlated electrons in which a strong coupling is observed between different characteristics of the material: structure, charge, spin [1]. This means that even a weak external stimulus can induce significant changes in properties, which we are exploiting to build sensors. For example, the potential of LSMO thin films for uncooled bolometric detection in the visible/near infrared range has been demonstrated at GREYC in recent years [2, 3].

Thanks to its expertise in bolometric detection, but also in active components on III-V components (diodes, Si- or GaN-based transistors) [4], GREYC’s Electronics team is proposing, through this thesis, to develop new innovative sensors based on LSMO-type functional oxides.

Heterostructures based on functional oxides could indeed exhibit a high signal-to-noise ratio (very high detection sensitivity) and a very fast response without a major cooling system. These new sensors could be state-of-the-art. This type of uncooled, high-sensitivity, fast-detection sensor could find numerous applications in several fields (ultra-fast UV photodetection for molecular spectroscopy or remote detection of pollutants, high-sensitivity SWIR detection, photodetection for ultra-fast SWIR LIDAR systems).

The points to be addressed during the thesis will be:
Production of thin-film oxide devices using pulsed laser ablation (PLD) and laser lithography
Study of electrical properties,
Study of defects using DLTFS (Deep Level Transient Fourier Spectroscopy).

Requested skills:
Master diploma or equivalent diploma. For this strong multidisciplinary subject, profiles based on/or merging competencies of electronics, sensors, physics, material physics and / or micro-technology clean room will be considered with a great attention. The proposed thesis is for curious, inventive, dynamic candidates having a strong scientific background and a sense of collaborative works. Experience of research and experimentation will be appreciated extra points.

3 years duration doctoral contract, The PhD thesis beginning is expected in October/November 2023.

Please send as soon as possible your application documents including a detailed CV, a motivation letter dedicated to the proposed position, marks and ranks you obtained during your master degree or engineering school, and reference letters.

Bruno Guillet
Professor at the university Caen Normandie,

GREYC (UMR 6072) www.greyc.fr
6 boulevard Maréchal Juin
14050 CAEN cedex (FRANCE)

[1] Towards Oxide Electronics: a Roadmap, M. Coll et al. Appl. Surf. Sci., 482, 1-94 (2019)
Sub-nT resolution of Single Layer Sensor Based on the AMR Effect in La2/3Sr1/3MnO3 Thin Films, L.G. Enger et al. IEEE Trans. Mag. (2021)| DOI: 10.1109/TMAG.2021.3089373.
Electro-thermal and optical characterization of an uncooled suspended bolometer based on an epitaxial La0.7Sr0.3MnO3 film grown on CaTiO3/Si, V.M. Nascimento et al. J. Phys. D: Appl. Phys. 54 055301 (2021) | DOI: 10.1088/1361-6463/abbfca; Free-standing La0.7Sr0.3MnO3 suspended microbridges on buffered silicon substrates showing undegraded low frequency noise properties, S. Liu et al. J. Micromech. Microeng. 29 065008 (2019)
Characterization of defect states in Mg-doped GaN-on-Si p+ n diodes using deep-level transient Fourier spectroscopy, Y. Lechaux et al. Semicond. Sci. Technol., 36, 2, 024002 (2020) https://doi.org/10.1088/1361-6641/abcb19 ; Impact of the in situ SiN Thickness on Low-Frequency Noise in MOVPE InAlGaN/GaN HEMTs, M. Rzin et al., IEEE Trans. Electron Devices, 66, 12, 580 (2019) DOI: 10.1109/TED.2019.2945296 ; Impact of Gate–Drain Spacing on Low-Frequency Noise Performance of In Situ SiN Passivated InAlGaN/GaN MIS-HEMTs, M. Rzin et al., IEEE Trans. Electron Devices, 64, 7, 2820 (2017) DOI: 10.1109/TED.2017.2703809