innovation for industry
awards & honors
Electrical junctions are essential to the proper functioning of integrated circuits. While they happen to only make up a small proportion of the total of a device’s weight, their manufacturing process requires a great deal of energy and materials. The process therefore must be optimized to reduce their impact while ensuring state-of-the-art performance. This is specifically the challenge on which Nada and Philippe have focused their research.
Following two years in a preparatory course in Morocco, and three years at Grenoble INP Phelma studying nanotechnology, Nada Zerhouni Abdou joined CEA-Leti for an internship, before doing her thesis on the characterization of SOI substrates using an EZ-FET. This device features several advantages in terms of planetary resources, since it requires significantly fewer stages compared to a standard transistor. Her device is now ready to be integrated into a low-temperature substrate for characterization following source and drain doping and dopant activation using nanosecond laser annealing. Next stage: finding an alternative for EZ-FET substrate integration that does not require doping. Nada received the Best Young Award for her innovating scientific results given her young age.
“During my internship, when I saw the mobile clean room go by, I knew that I wanted to do my thesis at CEA-Leti so that I could one day climb onboard, too!”
Following a PhD in materials chemistry, Philippe Rodriguez has been working at CEA-Leti for ten years. His research findings on germanium-tin (GeSn) junctions all involve the same issue: the instability of tin makes it quite fragile when contact between the two layers is created using regular annealing process, which can cause it to segregate. To tackle this, Philippe uses a nanosecond annealing process, which creates a solid-state reaction between nickel and the GeSn component. This both reduces the thermal budget and stabilizes the junction while retaining the desired photonic properties. Philippe received the Best Paper Award for a solution that could have a significant impact for the scientific community.
“Innovation is a collective process. By drawing on everyone’s expertise, we can go further to push the boundaries of possibility.”
Thomas Ernst received his degree in Electronics Engineering, his PhD, and accreditation for PhD supervision from the Grenoble Institut National Polytechnique (France). Following advanced SOI CMOS characterization and modelling with CNRS and STMicroelectronics, he joined CEA-Leti in 2000 to lead different research projects with industrial partners.His team published several improvements on stacked nanosheet gate-all-around transistors (called at that time nano-beams or MBCFET® by Samsung) in 2006 and later, in collaboration with STMicroelectronics using an original so-called silicon- on-nothing technology developed by CNET, STMicroelectronics and Leti. This technology is being introduced for sub 5nm CMOS. He is now scientific director at CEA-Leti, where he oversees long-term research strategies and scientific partnerships. In 2009, he received an ERC to study multiphysics integrated nano-sensors for complex gas analysis in collaboration with Caltech. He has also been a senior member of the Institute of Electrical and Electronics Engineers (IEEE) since 2015. With a portfolio of more than 20 patents, he has authored or co-authored more than 180 articles for technical journals and international conferences.
They are the hundreds of unit structures, ranging from 5 to 50 µm that can be seen on the surface of most insect eyes. These microlenses, which comprise an anti-reflective (AR) architecture, help a large amount of a light source converge toward photoreceptor cells, thus facilitating light trapping in dark environments. But that is not all, as these anti-reflective nanostructures also enable a surface's self-cleaning feature. For arthropods, this is a question of survival, while Raphaël sees it as a source of inspiration for improving energy efficiency in devices such as photovoltaic panels or imagers, which could greatly improve the trapping of light.
Grayscale lithography (300 mm) participates in creating microstructures which, through the self-assembly of block copolymers, can then integrate anti-reflective nanostructures. These two manufacturing processes make it possible to create and control complex or hierarchical microlens structures. For now, Raphaël has found an ideal compromise between assembly height and density, as the self-assembly of PS-b-PMMA ([polystyrene-block-poly(methyl methacrylate) copolymers on a non-planar surface remains challenging. This would therefore provide energy efficiency for high-power devices. Furthermore, the process has direct access to CEA-Leti’s industrial equipment.
Raphaël is continuing to look for the best way possible to implement this technological innovation, and he already has filed a patent.
Constantly yielding important breakthroughs, epitaxy research is an extremely dynamic field. Epitaxy involves developing techniques to produce high-quality monocrystalline films with specific properties. Accurately controlling film growth, doping, and heterostructure formation has turned the method into a crucial component for the semi-conductor industry, enhancing the performance, scalability, and integration of semi-conductors.
Justine studied the epitaxial growth of IV-IV semi-conductor materials such as Silicium-Germanium (SiGe) or doped silicon. Her research involved determining the growth characteristics and incorporation of dopants, which revealed potential applications for devices and made it possible to grasp their properties in a different light. Her next goal is to integrate this process into a device as a way of improving its energy efficiency. Attending conferences remotely rather than flying, Justine takes sustainable development issues to heart both in her everyday life and in epitaxy.
Marvin rose to the challenge of co-integrating innovative materials with standardized industry equipment by using the RP-CVD (Reduced Pressure-Chemical Vapor Deposition) process. A contact resistance reduced via strong doping levels and an improved electrical confinement were used to manufacture photodiodes on Silicon Germanium Tin (SiGeSn). They demonstrated improved light-emitting intensity when integrated in photonic devices compared with photodiodes that had doped Germanium (Ge) contact layers. The wavelength range covered by the photodiodes is promising for their use as CMOS-compatible components, including to detect gases inexpensively. Having developed an optical laser device that works at room temperature, Marvin's next goal is to design a laser that will work electrically under the same conditions.
Having begun her education in computer communication engineering at the Lebanese University of Engineering, Salam began a Master's degree in signal and image processing at Grenoble INP—Phelma. She then met CEA-Leti ambassadors, who offered her a position as a doctoral student, to work on mental health and artificial intelligence.
It's quite unique to be able to work in such a culturally rich environment, and I'm convinced that this is one of CEA-Leti's strengths.
Her interest in the workings of the human psyche led to three years researching and developing an embedded tool to understand and predict potential relapses in people who suffer from mental disorders and illnesses. Salam Hamieh only heard quite late that her supervisors had registered her for the challenge. Yet far from discouraging her, she obtained second place, with the aim of developing a tool:
A smartwatch that continuously analyzes a quantity of data that a doctor would be unable to analyze alone, and then interprets and accordingly informs the patient's specialists. The device presents a potentially viable and safe algorithm that may allow for a better understanding and prediction of relapse cases in patients suffering from bipolar disorders or schizophrenia, among other conditions.
By combining my understanding of field and circuit theories from my background in RF engineering, I came up with a successful design for a new solution. I am confident that my skills and experience will help me push the boundaries of what is possible in the field of Radio-frequency Engineering.”
The impetus for CEA-Leti innovations always begins with academic and industrial needs. Anthony Albanese's research on amorphous chalcogenide materials for highly nonlinear on-chip components confirm CEA-Leti's expertise at the forefront of More than Moore solutions.
After earning a scholarship to study in Grenoble, Anthony went on
to pursue a PhD at CEA-Leti, in collaboration with the Institut Carnot de Bourgogne. His aim was to explore energy efficiency issues through the inclusion of innovative materials in photonic systems while ensuring CMOS compatibility, which is essential to industrial transfer.
The chalcogenide materials he studied have promising optical properties and feature exceptional nonlinearity while retaining great transparency and good thermal stability. Special thanks go to Jean-Baptiste Dory, the former PhD student who launched the topic at CEA-Leti in 2016 under the supervision of Pierre Noé, at the Department of Advanced Material Deposition, and with Pierre's close collaborators from the University of Bourgogne in Dijon (Benoit Cluzel), FNRS at the University of Liège (Jean-Yves Raty) and at the ESRF of Grenoble with the Italian CRG beamline LISA (Francesco d'Acapito). This research make it possible to improve performance in the following areas: quantum computing, infrared sensors, telecommunications, and so much more.
Anthony had the opportunity to keep discussions going on new issues surrounding amorphous chalcogenide materials for highly nonlinear on-chip components and phase-change materials for on-chip active components and neuromorphic computing applications in the course of two oral presentations at the MRS 2022 Fall Meeting, in Boston, where he was selected for the Third Place in the judging of student presentations in Symposium
EQ04: Emerging Chalcogenide Electronic Materials – Theory to Applications. He was also able to share his knowledge and passion for materials engineering and solid-state physics through classes he gave to Master's students at INP Phelma, an experience he found extremely gratifying.
CEA-Leti has the best to offer. As a doctoral student, you are given total autonomy with a wide range of cutting edge technological tools and can collaborate with world-renowned researchers. It’s quite unique.
Space is not a very hospitable environment... especially for image sensors on orbiting satellites. Space missions are exposed to radiations from solar winds and cosmic rays. Ségolène Dinand devoted her PhD to better understanding how the radiation environment in space affects HgCdTe infrared detectors.
Over the course of her engineering studies, multiple internships in the space sector confirmed her interest in these issues. Ségolène went on to work with the European Space Agency for a year and a half, before joining CEA-Leti for her PhD, in partnership with the ISAE-Supaéro engineering institute and Airbus Defence and Space. Her PhD project was aligned not only with her scientific aspirations but also with her desire to root her research in practical applications.
In a first for her laboratory, Ségolène developed a characterization system to precisely analyze the effects of radiation on HgCdTe photodiodes. With access to the necessary equipment to cool her detectors to 90 K (-183°C), she was able to conduct experiments in conditions closely resembling those experienced by detectors in orbit. Her findings were presented at international conferences.
Her research will make it possible, firstly, to anticipate declining performance of HgCdTe detectors, and secondly, to identify parameters for increasing their resistance to ionizing and non-ionizing radiation. Orbiting infrared instruments play an essential role in greenhouse gas emissions monitoring, meteorology, astronomy and Earth observation.
CEA is a French government-funded technological research organisation in four main areas: low-carbon energies, defense and security, information technologies and health technologies. A prominent player in the European Research Area, it is involved in setting up collaborative projects with many partners around the world.