Nanotrench for nano and microparticle electrical interconnects

Abstract

We present a simple and versatile patterning procedure forthe reliable and reproducible fabrication of high aspect ratio (104) electrical interconnects that have separation distances down to 20 nm and lengths ofseveral hundreds of microns. The process uses standard optical lithography techniques andallows parallel processing of many junctions, making it easily scalable and industriallyrelevant. We demonstrate the suitability of these nanotrenches as electrical interconnectsfor addressing micro and nanoparticles by realizing several circuits with integrated species.Furthermore, low impedance metal–metal low contacts are shown to be obtained whentrapping a single metal-coated microsphere in the gap, emphasizing the intrinsic goodelectrical conductivity of the interconnects, even though a wet process is used. Highlyresistive magnetite-based nanoparticles networks also demonstrate the advantageof the high aspect ratio of the nanotrenches for providing access to electricalproperties of highly resistive materials, with leakage current levels below 1 pA.