Metal Assisted Chemical Etching (MacEtch) is an electroless chemical etching technique that has been largely used to create high aspect ratio nanostructures in silicon substrates. The main goal of this project is to use MacEtch for grating fabrication with characteristics that fulfill high energy and large field of view applications.
The grating fabrication team at TOMCAT has developed a mature process flow of grating fabrication, and is now pushing the limits of the fabrication technology with new designs and processing for improved gratings performance. We also bring the most advanced nano- and micro- processing technologies into the lab to overcome obstacles on the road to high quality gratings.
In this work, we investigate the use of a tailored optical element made of silicon structures in the submicrometer range to achieve higher spatial resolution and address other challenges of the method such as the non-uniformity of the phase sensitivity over the whole field of view of the speckle-based phase contrast X-ray imaging setup. The silicon nanostructures are created by metal assisted chemical etching (MacEtch) using gold as catalyst.