Vincent Vandalon

My academic interest can be summarized as follows: studying the growth of ultra-thin films by atomic-layer deposition and their characterization using advanced (nonlinear) optical diagnostics with an emphasis on their defects and non-idealities.

My most recent work was a postdoc focussing on the growth and characterization of 2D transition metal dichalcogenides (TMDs). In this project, I co-developed new ALD processes for the growth of these TMDs. Furthermore, I developed a new framework for texture characterization using Raman spectroscopy based upon new fundamental insight I obtained into the Raman response of nanocrystalline TMDs.

My PhD research encompassed mechanistic studies of the prototypical ALD processes for metal-oxide (thermal ALD of Al2O3) and for noble metal ALD (thermal ALD of Pt) using a new diagnostics: broadband sum-frequency generation (BB-SFG) spectroscopy. The surface chemistry during these processes was studied for the first time with this state-of-the-art technique which relies on the mixing of mid-IR and visible fs laser pulses. As such, SFG in a second-order nonlinear optical process making BB-SFG spectroscopy inherently surface sensitive. This property, combined with the all optical nature of BB-SFG, makes it ideally suited for in-situ studies of the surface chemistry. A purpose built setup was realized in the project and these BB-SFG studies revealed several key non-idealities in the growth mechanism of these well-studied prototypical ALD processes.

I also studyied the surface chemistry of plasma-enhanced ALD of Al2O3 using ATR-FTIR spectroscopy at the Colorado School of Mines (CSM) and I worked on the characterization of the SiO2/Si and Al2O3/Si interface relevant for nano-electronic and photovoltaic devices with phase-sensitive second-harmonic generation (SHG) spectroscopy. In conjunctino to probing the electronic structure of the interface, SHG can also reveal and quantify the presence of built-in charges near these interfaces which is a key property for device fabrication.

Apart from my passion for physics, I am also interested in computer science which resulted in e.g.  a project at the department of Mathematics and Computer Science performing real-time visualization of the execution of computer code.