SBIR Phase I: Batch Fabrication of High Aspect Ratio Metallic AFM Probes

This Small Business Innovation Research Phase I project is to demonstrate the feasibility of batch fabricating high-aspect ratio atomic force microscopy (AFM) probes. These probes have excellent mechanical and electrical properties and are customizable to a wide range of applications and substrates. Currently each probe is individually fabricated by dipping a silver-coated probe into melted gallium at room temperature, resulting in the self-assembly of a long, constant-diameter metal nanoneedle on the probe tip. Current production throughput is only five probes per hour. Because of their unique form and function there is a growing demand for these probes which can only be met if they are fabricated in parallel. In Phase I, a batch process will be developed, with the goal of moderate yield (25%) over a 1 cm square area. One innovative aspect of the project is the use of a gallium coated substrate that has an elastomeric underlayer to provide a degree of self-alignment that ensures intimate contact of the thick gallium film layer with surfaces that are not perfectly flat. The extension of this concept - in future studies - to the patterning of arrays of freestanding nanoneedles over curved and multilevel substrates appears reasonable. Based on the attainment of adequate yields in Phase I, Phase II will focus on the development of a semi-automated tool for wafer-scale growth of probes. The broader impact/commercial potential of this project is a dramatically increased commercial viability of a new kind of specialized AFM probe. The total market for AFM probes is $385 million, of which up to $100 million is addressable, if such probes can be fabricated in larger quantities. Since the launch of this technology in late 2008, customer feedback has been overwhelmingly positive. Current customers of these probes have made it clear that this new probe technology represents an enabling tool which will help advance and accelerate the pace of research and discovery in areas including nanomanipulation, biophysical probing, nanomechanics, nanoelectronics and metrology. The long range economic and societal impact will be a new manufactured product which will help to maintain U.S. leadership in nanotechnology and create high-paying technical jobs for scientists and engineers in Kentucky, a state where such opportunities have traditionally been extremely limited.