C. Muratore¹, B. Roberson¹, M. K. Muratore¹, N.R. Glavin^2
1University of Dayton, Dayton OH
²Air Force Research Laboratory, Wright-Patterson AFB, OH
Materials with nanoscale proportions possess high surface-to-volume ratios and therefore demonstrate exquisite sensitivity in diverse molecular sensing applications. Integration of nanowires, nanotubes, and two-dimensional (2D) semiconductors into sensing devices, however, presents challenges inhibiting product development. For example, thousands of trials are required to obtain US government approval for point of care medical diagnostics, yet producing a suitable number of 2D devices via conventional synthesis and fabrication techniques to meet this testing requirement is not currently feasible. To realize commercial applications of 2D transducers in ubiquitous low-cost diagnostic devices, new synthesis and fabrication approaches were developed. Processes for high-rate (>10⁶ per day) mass-production of low-cost two-dimensional electronic medical diagnostic devices with limits of detection rivalling polymerase chain reaction (PCR) based techniques (<10 fg/mL) with response times of <2 minutes will be presented. Rapid and inexpensive sensor device fabrication relies upon sputter deposition, laser pattering, and laser annealing processes in a roll-to-roll physical vapor deposition system. Moreover, naturally abundant and recyclable materials were selected for use in these scaled processes for reduced waste stream impact in anticipation of large numbers of devices are consumed daily. An automated high-speed Raman spectroscopy system was developed for quality control of mass-produced materials during fabrication. Fundamental studies employing this system to measure point defect densities in 2D semiconducting transducer materials will be shown to correlate synthesis and fabrication process parameters, 2D materials structure, and diagnostic device performance.