Dr. Marien Simeni
Assistant Professor
Mechanical Engineering Department
University of Minnesota

Abstract

The fourth state of matter, commonly referred to as “plasma,” plays a significant role in our everyday lives on Earth. Examples abound, ranging from its use as light sources to virus inactivation and high-volume manufacturing. Particularly noteworthy is the semiconductor industry, which greatly benefits from advancements in the field of plasma. In light of the quantum computing era and the semiconductor industry’s shift from microelectronics to nanoelectronics, the optimization of plasma processes has become more crucial than ever.

In the initial segment of this presentation, I will discuss the ongoing research endeavors of my group, focusing on comprehending fundamental plasma properties. The ultimate aim is to enhance the efficiency of extreme ultraviolet lithography, the current leading technology for patterning surfaces at the nanometer scale. Our emphasis will be on electron properties and their correlation with radiation transport.

Moving on to the second part of this discussion, I will showcase the foundational work undertaken by my group to develop innovative laser-based techniques for probing plasma properties at both the picosecond temporal scale and micrometer spatial scale. A particular highlight will be the exploration of three-wave mixing in the gas phase—a process once considered forbidden but now holding great promise for high-sensitivity number density measurements of both atomic and molecular species. To conclude, I will show how my group recently improved the detection limit of the electric field induced second harmonic generation (E-FISH) diagnostic by two orders of magnitude, to 1 V/cm under atmospheric pressure conditions. Such an improvement opens up multiple opportunities for testing fundamental plasma physics theories and scaling laws.

Biography

Marien Simeni is an Assistant Professor at the Mechanical Engineering Department of the University of Minnesota (UMN), where he started in April 2022. His research group focuses on the development of ultrafast laser diagnostics to unravel kinetic mechanisms and energy transfers in non-equilibrium and laser-produced plasmas as well as in reactive flows. Marien received his B.S. in physics from Ecole Normale Superieure Cachan (France) in 2009, his M.S. in aerospace engineering from Ecole Centrale Paris (France) in 2011 and his Ph.D. in aerospace engineering from the same institution in 2015. He subsequently held a postdoctoral position at the Ohio State University (2015-2018), a research associate position at UMN (2018-2020) and an associate research physicist position at the Princeton Plasma Physics Laboratory (2020-2022). Marien is a recipient of the 2024 D.O.E Early Career award.

Thursday, September 26. 2024
4:10 pm seminar

zoom link upon request