Collaboration between FOM and FEI bears fruit
On 6 July, Vincenzo Castaldo and Ernst Jan Vesseur were awarded their PhDs. They are the first to have gained a PhD within the FOM-FEI Industrial Partnership Programme (IPP) 'Microscopy and modification of nano-structures with focused electron and ion beams'. The IPP focuses on microscopes that use electron beams or ion beams instead of visible light. Ultimately, the researchers hope to be able to process materials and render these visible at the scale of a single atom. The programme has been running since 2007 and is being led by Prof. Pieter Kruit of Delft University of Technology.
Kruit's group had already been collaborating with FEI, one of the biggest suppliers of electron microscopes, for a long time. Since 2007, they have worked together in the context of an IPP. "We now have very intensive contact, once every two weeks. In this IPP, we are also getting to know other academic research partners of FEI, such as a group at Eindhoven University of Technology and the FOM Institute AMOLF," says Kruit. He explains that this leads to fantastic results at both a fundamental and applied level: "For example, we have a better understanding of the possibilities and limitations of ion microscopes, which is important for academic research as well as commercial use. In another project within the IPP, software procedures have been made to process images. These are already being integrated into FEI's systems."
Ion microscopes
Vincenzo Castaldo (Delft University of Technology) specialised in ion microscopes. Ions have a greater mass than electrons. In theory, this results in sharper images because according to quantum mechanics heavier particles have a shorter wavelength. Due to this mass, however, the ions also cause more damage to the sample. "Fortunately there are many different types of ions. Therefore, in principle, we can use lighter ions for imaging and heavier ions to modify materials at the nanoscale," says Castaldo. He studied the resolution of ion microscopes and examined the possibilities of existing microscopes. "The majority of ion microscopes are based on heavy metal ions, which are easy to obtain. However, I have also worked on the implementation of a new microscope that uses helium."
Optical nano-antennae
The research of Ernst Jan Vesseur (AMOLF) mostly focused on the manufacture of 'optical nano-antennae'. These antennae can capture light in a highly efficient manner. And if an electron beam is aimed at the antennae then they can also be used to emit light. The research has led to an application of the electron microscope with which researchers can learn more about light at very small length scales. Vesseur is very pleased about the conclusion of his PhD research: "Just a few months before the deadline for my thesis we came up with another idea for a new experiment. We managed to build the set-up, perform the measurements, and analyse the results in a very short period of time. That led to an extra chapter in my thesis with results that I am really proud of."
Public-private partnership
IPPs are research programmes in which FOM unites academic knowledge with industrial ambitions by means of groundbreaking physics research in close collaboration with industry. Companies involved in the programmes fund at least 50% of the research.
Further information
Ernst Jan Vesseur defended his PhD on 6 July at 14:30 hours in the Academiegebouw of Utrecht University (Domplein 29, Utrecht). At 13.30 hours he gave a presentation of his research for the general public.
Vincenzo Castaldo defended his PhD on 6 July at 15:00 hours in the Science Centre of Delft University of Technology (Mijnbouwstraat 120, Delft).