Laser In-Situ Diagnostics and Processing Probes for Electron Microscopes

Advanced electron microscopy and micro-characterization capabilities are critical for research in the materials and biological sciences and in particular for the development of nanotechnology to answer the growing needs to protect our environment, increase energy efficiency and develop clean energy sources. Achieving a fundamental understanding of materials nucleation and growth phenomena at the nanoscale is critical for nanotechnology and necessitates an experimental environment in which the important atomistic processes can be studied as they are occurring. The proposed innovation is based on a revolutionary, yet practical method for simultaneous nanoscale imaging of nanofabrication processes by integrating tip-based pulsed laser radiation sources within a transmission electron microscope. Nanoscale confinement of radiation fields of enhanced intensity underneath a tip-based probe enables a wide range of materials modification processes that open up an entirely new avenue for the definition and processing of nanostructures, while at the same time allowing for direct in-situ observation of the fundamental processes. During our Phase I project, we demonstrated delivery of a laser beam in optical near-field to a sample inside a transmission electron microscope for an in-situ imaging of a material undergoing nano-scale melting and recrystallization. This new capability remarkably enabled observation of the conversion of amorphous nanodomain precursors to single nanocrystals. The prototype in-situ probe holder developed during the Phase I project combines (a) photonic (laser) excitation in nanoscale, (b) in-situ transmission electron microscope imaging, and (c) simultaneous optical spectroscopic characterization of material properties. In this Phase II project, we will develop this prototype into a viable commercial product, a modular attachment kit to standard electron microscope instruments, to provide researchers in all aspects of science and technology with a powerful research tool to push the frontiers of science. This will be accomplished with systematic experiments to determine the optimal optical probe and detector configurations and the design and assembly of a prototype. Furthermore, the prototype will be tested in the real scientific studies of in-situ characterization of nanowire growth and the synthesis of nanostructures. The proposed product will enable a widespread adoption of unique facility for the in-situ nanoscale observation of laser material modification and nanomaterials growth processes. This entirely new capability will have a profound impact to the fields of materials science, nanofabrication, and the adoption of nanotechnology into marketplace.