​​​Congratulations to Justine LESPIAUX and Marvin FRAUENRATH ​​for their Best Student Presentation award at the 2022 ECS!

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.

The CEA-Leti ecosystem is very rich; it's impossible not to expand my field of knowledge. Additionally, research is focusing more on environmental responsibility. This has a real impact on my professional and personal decisions."

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.