MAE Seminar: Direct-write Helium Ion Lithography of High-transition Temperature Superconducting Electronics

Abstract: The 1987 discovery of high-T_C superconductivity in ceramic materials at temperatures around 90K set off a frenzy of research in the development of high-T_C electronics, motivated by the prospects of electronics operating in liquid nitrogen at 77K opposed to 4K liquid helium. Unfortunately, researchers soon discovered that these new materials were much more difficult to process than conventional metal superconductors. High-T_C materials are very anisotropic and the superconducting properties vary along the different crystallographic directions, which complicates manufacturing of the basic building blocks of superconducting electronics: Josephson junctions. Furthermore, the length scale of superconductivity in high-T_C ceramics is very short compared to low-T_C metals. Despite these challenges many high-T_C Josephson junction manufacturing techniques have emerged over the last three decades but none is able to generate large numbers of junctions with predictable characteristics necessary for large-scale circuits. Recently, my group has demonstrated a new scalable nanomanufacturing method of high‑T_C electronics using the finely focused beam from a helium ion microscope, which has the potential to deliver large numbers of high-quality circuits while at the same time reducing their costs by orders of magnitude. In this seminar, I will present some of the novel characteristics and applications of this new remarkable technology, including biomedical sensors for neural imaging and advanced wide-bandwidth electrically small antennas.

 

Bio: Professor Shane Cybart is the principal investigator of the Oxide Nano Electronics Laboratory at UC Riverside. He obtained a PhD in materials science from UC San Diego in 2005 studying high-transition-temperature Josephson devices. He continued his work in superconducting electronics as a postdoctoral researcher at UC Berkeley 2006-2009. More recently, he served as a project scientist at UC Berkeley and the Lawrence Berkeley Laboratory working on multiferroic and magnetic oxides. From 2013-2016, he led a group at UC San Diego developing oxide electronic devices for a diverse range of applications. In June 2016 he joined the Department of Mechanical Engineering and Materials Science and Engineering Program at University of California Riverside. His group studies the basic science and applications of Josephson devices.