The current scientific interest and next generation of nanotechnology-based products is combining converging fields and dealing with a large complexity (e.g. organic electronics, nanomedicine). The growing needs to visualize, manipulate, modify and characterize nano-objects in a single tool is addressed by UnivSEM project. Some examples could be found below.
This image shows a fractal antenna structure in a single crystalline gold flake. It was fabricated by a precisely focused ion beam of a Lyra 3 prototype that was developed in the Fiblys EU project. Inside the Fiblys project, the microscope was equipped with many characterization techniques, focusing on topography or chemical composition. Unfortunately, there was no method for in-situ optical characterization techniques like photoluminescence, Raman-spectroscopy or cathodoluminescence.
For this purpose the UnivSEM project develops a highly innovative combination of an electron and an optical microscope in one single system. Here it will be possible to fabricate optically active nanostructures and analyze them subsequently in situ with optical methods. This prevents contamination or oxidation of sensitive materials and enables a new type and quality of experiments.
Various applications of plasmonic nanoantennas is foreseen. Due to local and controllable field enhancements, sensor application could be the first one, where even single molecules can be detected. Antenna arrays can act as structures for surface enhanced Raman spectroscopy. Plasmonic waveguides are also promising structures for future optical connections on next-generation computer chips. Plasmons can transmit information at much higher frequencies than in today’s silicon based chips. Last but not least, plasmonic nanostructures can increase solar cell efficiencies due to improved interaction with light and a better light coupling to the solar cell material.
As well as the gold nanoflakes in the first image, silver nanowires (AgNWs) can also be easily grown by a simple wet-chemical approach. This colorful micrograph shows a pile of AgNWs, visualized with three forescatter electron detector diodes. The diodes are coded in RGB color space and the diversity of colors is created by topography and shading of single diodes. Silver nanowires can form a transparent conductive network and thus are a promising candidate for solar cell contacts or transparent layers in displays.
3D visualization of FIB-TOFSIMS data has been greatly improved by EMPA within UnivSEM project. The image above shows the distribution of aluminium in a semiconductor laser; some of the layers form a highly reflective mirror at the laser wavelength. Field of view 20 x 20 x 1.5 micrometers.