This Faculty Early Career Development (CAREER) grant will investigate the newly discovered ?water-in-salt? electrolytes, which will potentially enable the fabrication of superconductors for applications in quantum devices. A superconductor is a unique material that allows an electrical current to flow without experiencing any resistance, providing for tremendous advances in energy efficiency and computing applications. Low temperature quantum computers and other cryogenic electronic devices require superconducting wirings to avoid resistive heating, which increases the temperature and perturbs the performance of those devices. The wiring in conventional integrated circuits has been manufactured using electrodeposition processes, but such a process is not available for superconductors. Films electrodeposited from conventional electrolytes lack structural precision, and the superconductivity degrades when the films are further processed into complete circuits. This project will focus on the development of a new ?water-in-salt? electrolyte that is expected to improve the film structures. This work will provide a fundamental understanding of the deposition chemistry and the process, as well as how these factors impact the morphology and superconductivity of the films. The goal is to enable such electrodeposition processes for the industrial manufacturing of superconducting circuits. Collaborations with a local children?s museum and local high schools will be established and strengthened, in order to promote the awareness of science and engineering education and careers among K-12 students and parents, particularly from underrepresented groups. In addition, the research results will contribute to the development of new class modules for the undergraduate/graduate-level course: ?Electrochemical Engineering and Microfabrication.?
Water-in-salt can be viewed as an aqueous electrolyte without free water, as the hydration of a super high concentration of salt depletes the water molecules. This is due to the formation of sheaths of water around the ions, resulting in a much suppressed reduction of protons and water. This project takes advantage of such water-in-salt electrolytes to enable new electrodeposition processes for superconducting film fabrication, aiming to provide fundamental understandings of: i) how the speciation and concentration of solutes impact the incorporation and distribution of hydrogen and other impurity elements; ii) how electrodeposition processes such as voltage bias, pulse duration, and hydrodynamics influence the nucleation and growth, film stress, and grain structure; and iii) how the substrates, stress layers, capping layers, and thermal annealing processes may change the grain structure, impurity distribution, outgassing, film stress, and superconductivity. This project also aims to integrate this knowledge into the design of deposition processes, in conjunction with the electrolyte, to enable superconductor circuit manufacturing. This project will allow the Principal Investigator to advance the knowledge base in Electrochemical Engineering, Material Sciences, Superconducting and Electronic Devices, and establish his long-term career in advanced manufacturing.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
