SBIR Phase II: Low Temperature Ion Source for High-Brightness Focused Ion Beams

This Small Business Innovation Research (SBIR) Phase II project will develop low-temperature ion source (LoTIS) technology which uses laser-cooling to create a beam of Cs+ ions with high brightness and low energy spread. This technology will extend the utility of focused ion beam (FIB) instrumentation that is widely used for nanometer-scale precision machining tasks; it accomplishes this by addressing shortcomings in precision and speed afforded by commercially available ion sources. One primary research aim of this project is the measurement of a key ion source performance metric, namely brightness, in order to compare its value to that of incumbent ion source technologies. LoTIS may have a brightness that is tenfold to one hundred-fold larger than the industry standard liquid metal ion source. An ion source with such an improved brightness would enable superior machining precision at higher speeds over a broader range of ion beam operating energies. The broader impact/commercial potential of this project is to develop improved FIB instrumentation to empower users in a variety of research fields and industrial applications, including nanotechnology, biotechnology, semiconductor manufacturing, and energy exploration. In particular, nanomachining applications, including integrated circuit edit and rapid prototyping of nanoscale device structures, are increasingly limited by the precision afforded by current ion source technology, and the users in these areas are in need of higher-precision FIBs. FIBs employed for transmission electron microscope lamellae preparation require less precision but could benefit from reduced subsurface ion damage provided by this method, through the use of Cs+ ions at low energy. A bright source of Cs+ ions could also dramatically improve the resolution and throughput for spatially-resolved elemental mapping in secondary ion mass spectrometry (SIMS) applications. This technique represents an order-of-magnitude ion source performance improvement that will address FIB user needs across a wide spectrum of scientific and commercial applications.